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FDA Approves First Engineered Cell Therapy for a Solid Tumor
Afami-cel — the first engineered cell therapy for a solid tumor — is indicated specifically for adults with unresectable or metastatic synovial sarcoma who have received prior chemotherapy, are positive for several human leukocyte antigens (HLAs), and whose tumors express melanoma-associated antigen A4, as determined by FDA-authorized companion diagnostic devices.
The single-dose treatment targets solid tumors expressing melanoma-associated antigen A4, a protein highly expressed in synovial sarcoma.
Synovial sarcoma is a rare form of cancer, which affects about 1000 people in the US each year. Malignant cells develop and form a tumor in soft tissues, often in the extremities.
“Adults with metastatic synovial sarcoma, a life-threatening form of cancer, often face limited treatment options in addition to the risk of cancer spread or recurrence,” Nicole Verdun, MD, director of the Office of Therapeutic Products in the FDA’s Center for Biologics Evaluation and Research, said in the agency press release announcing the approval. “Today’s approval represents a significant milestone in the development of an innovative, safe and effective therapy for patients with this rare but potentially fatal disease.”
T-cell receptor therapy, like chimeric antigen receptor (CAR) T-cell (CAR-T) therapy, involves altering patient T cells to fight cancer. While CAR-T therapy inserts an artificial receptor to target a specific surface protein on cancer cells, the T-cell receptor therapy modifies existing receptors to recognize an array of antigens on the surface of cancer cells — a promising strategy for targeting solid tumors.
The accelerated approval of afami-cel was based on the phase 2 SPEARHEAD-1 trial in 44 patients with synovial sarcoma who received a single infusion of the therapy. The trial had enrolled 52 patients, but 8 did not receive afami-cel, including 3 who died and 1 who withdrew.
According to the FDA announcement, the overall response rate was 43.2%, with a median time to response of 4.9 weeks. The median duration of response was 6 months (95% CI, 4.6 months to not reached). Among patients who responded, 39% had a duration of response of 12 months or longer.
“These results suggest that a one-time treatment with afami-cel has the potential to extend life while allowing responders to go off chemotherapy,” said lead investigator Sandra D’Angelo, MD, a sarcoma specialist at Memorial Sloan Kettering Cancer Center in New York City, in a company press release.
The prescribing information includes a boxed warning for serious or fatal cytokine release syndrome.
The most common nonlaboratory adverse reactions, occurring in at least 20% of patients, included cytokine release syndrome, nausea, vomiting, fatigue, infections, pyrexia, constipation, dyspnea, tachycardia, hypotension, diarrhea, and edema. The most common grade 3 or 4 laboratory abnormalities, occurring in at least 20% of patients, included decreased lymphocyte count, neutrophil count, white cell blood count, red blood cell, and platelet count.
The recommended dose is between 2.68x109 to 10x109 MAGE-A4 T-cell receptor–positive T-cells. The FDA notice specifies not using a leukodepleting filter or prophylactic systemic corticosteroids.
The list price for the one-time therapy is $727,000, according to Fierce Pharma.
A version of this article first appeared on Medscape.com.
Afami-cel — the first engineered cell therapy for a solid tumor — is indicated specifically for adults with unresectable or metastatic synovial sarcoma who have received prior chemotherapy, are positive for several human leukocyte antigens (HLAs), and whose tumors express melanoma-associated antigen A4, as determined by FDA-authorized companion diagnostic devices.
The single-dose treatment targets solid tumors expressing melanoma-associated antigen A4, a protein highly expressed in synovial sarcoma.
Synovial sarcoma is a rare form of cancer, which affects about 1000 people in the US each year. Malignant cells develop and form a tumor in soft tissues, often in the extremities.
“Adults with metastatic synovial sarcoma, a life-threatening form of cancer, often face limited treatment options in addition to the risk of cancer spread or recurrence,” Nicole Verdun, MD, director of the Office of Therapeutic Products in the FDA’s Center for Biologics Evaluation and Research, said in the agency press release announcing the approval. “Today’s approval represents a significant milestone in the development of an innovative, safe and effective therapy for patients with this rare but potentially fatal disease.”
T-cell receptor therapy, like chimeric antigen receptor (CAR) T-cell (CAR-T) therapy, involves altering patient T cells to fight cancer. While CAR-T therapy inserts an artificial receptor to target a specific surface protein on cancer cells, the T-cell receptor therapy modifies existing receptors to recognize an array of antigens on the surface of cancer cells — a promising strategy for targeting solid tumors.
The accelerated approval of afami-cel was based on the phase 2 SPEARHEAD-1 trial in 44 patients with synovial sarcoma who received a single infusion of the therapy. The trial had enrolled 52 patients, but 8 did not receive afami-cel, including 3 who died and 1 who withdrew.
According to the FDA announcement, the overall response rate was 43.2%, with a median time to response of 4.9 weeks. The median duration of response was 6 months (95% CI, 4.6 months to not reached). Among patients who responded, 39% had a duration of response of 12 months or longer.
“These results suggest that a one-time treatment with afami-cel has the potential to extend life while allowing responders to go off chemotherapy,” said lead investigator Sandra D’Angelo, MD, a sarcoma specialist at Memorial Sloan Kettering Cancer Center in New York City, in a company press release.
The prescribing information includes a boxed warning for serious or fatal cytokine release syndrome.
The most common nonlaboratory adverse reactions, occurring in at least 20% of patients, included cytokine release syndrome, nausea, vomiting, fatigue, infections, pyrexia, constipation, dyspnea, tachycardia, hypotension, diarrhea, and edema. The most common grade 3 or 4 laboratory abnormalities, occurring in at least 20% of patients, included decreased lymphocyte count, neutrophil count, white cell blood count, red blood cell, and platelet count.
The recommended dose is between 2.68x109 to 10x109 MAGE-A4 T-cell receptor–positive T-cells. The FDA notice specifies not using a leukodepleting filter or prophylactic systemic corticosteroids.
The list price for the one-time therapy is $727,000, according to Fierce Pharma.
A version of this article first appeared on Medscape.com.
Afami-cel — the first engineered cell therapy for a solid tumor — is indicated specifically for adults with unresectable or metastatic synovial sarcoma who have received prior chemotherapy, are positive for several human leukocyte antigens (HLAs), and whose tumors express melanoma-associated antigen A4, as determined by FDA-authorized companion diagnostic devices.
The single-dose treatment targets solid tumors expressing melanoma-associated antigen A4, a protein highly expressed in synovial sarcoma.
Synovial sarcoma is a rare form of cancer, which affects about 1000 people in the US each year. Malignant cells develop and form a tumor in soft tissues, often in the extremities.
“Adults with metastatic synovial sarcoma, a life-threatening form of cancer, often face limited treatment options in addition to the risk of cancer spread or recurrence,” Nicole Verdun, MD, director of the Office of Therapeutic Products in the FDA’s Center for Biologics Evaluation and Research, said in the agency press release announcing the approval. “Today’s approval represents a significant milestone in the development of an innovative, safe and effective therapy for patients with this rare but potentially fatal disease.”
T-cell receptor therapy, like chimeric antigen receptor (CAR) T-cell (CAR-T) therapy, involves altering patient T cells to fight cancer. While CAR-T therapy inserts an artificial receptor to target a specific surface protein on cancer cells, the T-cell receptor therapy modifies existing receptors to recognize an array of antigens on the surface of cancer cells — a promising strategy for targeting solid tumors.
The accelerated approval of afami-cel was based on the phase 2 SPEARHEAD-1 trial in 44 patients with synovial sarcoma who received a single infusion of the therapy. The trial had enrolled 52 patients, but 8 did not receive afami-cel, including 3 who died and 1 who withdrew.
According to the FDA announcement, the overall response rate was 43.2%, with a median time to response of 4.9 weeks. The median duration of response was 6 months (95% CI, 4.6 months to not reached). Among patients who responded, 39% had a duration of response of 12 months or longer.
“These results suggest that a one-time treatment with afami-cel has the potential to extend life while allowing responders to go off chemotherapy,” said lead investigator Sandra D’Angelo, MD, a sarcoma specialist at Memorial Sloan Kettering Cancer Center in New York City, in a company press release.
The prescribing information includes a boxed warning for serious or fatal cytokine release syndrome.
The most common nonlaboratory adverse reactions, occurring in at least 20% of patients, included cytokine release syndrome, nausea, vomiting, fatigue, infections, pyrexia, constipation, dyspnea, tachycardia, hypotension, diarrhea, and edema. The most common grade 3 or 4 laboratory abnormalities, occurring in at least 20% of patients, included decreased lymphocyte count, neutrophil count, white cell blood count, red blood cell, and platelet count.
The recommended dose is between 2.68x109 to 10x109 MAGE-A4 T-cell receptor–positive T-cells. The FDA notice specifies not using a leukodepleting filter or prophylactic systemic corticosteroids.
The list price for the one-time therapy is $727,000, according to Fierce Pharma.
A version of this article first appeared on Medscape.com.
The Last 30 Days: How Oncologists’ Choices Affect End-of-Life Cancer Care
TOPLINE:
Patients treated by oncologists in the top quartile for end-of-life prescribing behavior were almost four and a half times more likely to receive end-of-life therapy than those treated by these specialists in the bottom quartile.
METHODOLOGY:
- Researchers analyzed data from the Surveillance, Epidemiology, and End Results (SEER)-Medicare database, focusing on patients who died of cancer between 2012 and 2017.
- A total of 17,609 patients with breast, lung, colorectal, or prostate cancer were included, treated by 960 oncologists across 388 practices.
- Patients were required to have had at least one systemic cancer therapy claim in the last 180 days of life, with the treating oncologist identified on the basis of the therapy claim closest to the time of death.
- The study used multilevel models to estimate oncologists’ rates of providing cancer therapy in the last 30 days of life, adjusting for patient characteristics and practice variation.
- Functional status was assessed on the basis of paid claims for durable medical equipment in the last 60 months of life, with scores categorized as 0, 1, ≥ 2, or unknown.
TAKEAWAY:
- Oncologists in the 95th percentile for high end-of-life prescribing behavior had a 45% adjusted rate of treating patients in the last 30 days of life, compared with 17% among those in the 5th percentile.
- Patients treated by high end-of-life prescribing oncologists had over four times higher odds of receiving systemic therapy in the last 30 days of life (odds ratio [OR], 4.42; 95% CI, 4.00-4.89).
- Higher end-of-life prescribing oncologists also had a higher proportion of patients hospitalized in the last 30 days of life than low prescribers (58% vs 51.9%).
- No significant association was found between oncologist prescribing behavior and patient race or ethnicity, except for Black patients who had lower odds of receiving treatment (OR, 0.77; P < .001).
IN PRACTICE:
“Given calls to rein in overutilization of end-of-life six to eight cancer therapies, our findings highlight an underappreciated area for further research: How treatment discontinuation before death is shaped by oncologists’ unique treatment propensities. Elucidating the reasons for this remarkable variability in oncologist treatment behavior could inform efforts to reduce end-of-life cancer treatment overutilization,” wrote the authors of the study.
SOURCE:
The study was led by Login S. George, PhD, Institute for Health, Health Care Policy and Aging Research, Rutgers University in New Brunswick, New Jersey. It was published online in Cancer.
LIMITATIONS:
The study’s reliance on SEER-Medicare data may limit the generalizability of the findings to patients with Medicare Advantage, private insurance, or Medicaid, as well as younger patients. The lack of data on patient preferences and other health characteristics could confound the results. The study focused on systemic therapies and may not be generalizable to other treatments such as clinical trial drugs, oral therapies, surgery, or radiation. The data from 2012 to 2017 may not reflect more recent trends in cancer treatment.
DISCLOSURES:
The study was supported by grants from the National Cancer Institute and the Rutgers Cancer Institute of New Jersey. George disclosed receiving grants from these organizations. Additional disclosures are noted in the original article.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article first appeared on Medscape.com.
TOPLINE:
Patients treated by oncologists in the top quartile for end-of-life prescribing behavior were almost four and a half times more likely to receive end-of-life therapy than those treated by these specialists in the bottom quartile.
METHODOLOGY:
- Researchers analyzed data from the Surveillance, Epidemiology, and End Results (SEER)-Medicare database, focusing on patients who died of cancer between 2012 and 2017.
- A total of 17,609 patients with breast, lung, colorectal, or prostate cancer were included, treated by 960 oncologists across 388 practices.
- Patients were required to have had at least one systemic cancer therapy claim in the last 180 days of life, with the treating oncologist identified on the basis of the therapy claim closest to the time of death.
- The study used multilevel models to estimate oncologists’ rates of providing cancer therapy in the last 30 days of life, adjusting for patient characteristics and practice variation.
- Functional status was assessed on the basis of paid claims for durable medical equipment in the last 60 months of life, with scores categorized as 0, 1, ≥ 2, or unknown.
TAKEAWAY:
- Oncologists in the 95th percentile for high end-of-life prescribing behavior had a 45% adjusted rate of treating patients in the last 30 days of life, compared with 17% among those in the 5th percentile.
- Patients treated by high end-of-life prescribing oncologists had over four times higher odds of receiving systemic therapy in the last 30 days of life (odds ratio [OR], 4.42; 95% CI, 4.00-4.89).
- Higher end-of-life prescribing oncologists also had a higher proportion of patients hospitalized in the last 30 days of life than low prescribers (58% vs 51.9%).
- No significant association was found between oncologist prescribing behavior and patient race or ethnicity, except for Black patients who had lower odds of receiving treatment (OR, 0.77; P < .001).
IN PRACTICE:
“Given calls to rein in overutilization of end-of-life six to eight cancer therapies, our findings highlight an underappreciated area for further research: How treatment discontinuation before death is shaped by oncologists’ unique treatment propensities. Elucidating the reasons for this remarkable variability in oncologist treatment behavior could inform efforts to reduce end-of-life cancer treatment overutilization,” wrote the authors of the study.
SOURCE:
The study was led by Login S. George, PhD, Institute for Health, Health Care Policy and Aging Research, Rutgers University in New Brunswick, New Jersey. It was published online in Cancer.
LIMITATIONS:
The study’s reliance on SEER-Medicare data may limit the generalizability of the findings to patients with Medicare Advantage, private insurance, or Medicaid, as well as younger patients. The lack of data on patient preferences and other health characteristics could confound the results. The study focused on systemic therapies and may not be generalizable to other treatments such as clinical trial drugs, oral therapies, surgery, or radiation. The data from 2012 to 2017 may not reflect more recent trends in cancer treatment.
DISCLOSURES:
The study was supported by grants from the National Cancer Institute and the Rutgers Cancer Institute of New Jersey. George disclosed receiving grants from these organizations. Additional disclosures are noted in the original article.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article first appeared on Medscape.com.
TOPLINE:
Patients treated by oncologists in the top quartile for end-of-life prescribing behavior were almost four and a half times more likely to receive end-of-life therapy than those treated by these specialists in the bottom quartile.
METHODOLOGY:
- Researchers analyzed data from the Surveillance, Epidemiology, and End Results (SEER)-Medicare database, focusing on patients who died of cancer between 2012 and 2017.
- A total of 17,609 patients with breast, lung, colorectal, or prostate cancer were included, treated by 960 oncologists across 388 practices.
- Patients were required to have had at least one systemic cancer therapy claim in the last 180 days of life, with the treating oncologist identified on the basis of the therapy claim closest to the time of death.
- The study used multilevel models to estimate oncologists’ rates of providing cancer therapy in the last 30 days of life, adjusting for patient characteristics and practice variation.
- Functional status was assessed on the basis of paid claims for durable medical equipment in the last 60 months of life, with scores categorized as 0, 1, ≥ 2, or unknown.
TAKEAWAY:
- Oncologists in the 95th percentile for high end-of-life prescribing behavior had a 45% adjusted rate of treating patients in the last 30 days of life, compared with 17% among those in the 5th percentile.
- Patients treated by high end-of-life prescribing oncologists had over four times higher odds of receiving systemic therapy in the last 30 days of life (odds ratio [OR], 4.42; 95% CI, 4.00-4.89).
- Higher end-of-life prescribing oncologists also had a higher proportion of patients hospitalized in the last 30 days of life than low prescribers (58% vs 51.9%).
- No significant association was found between oncologist prescribing behavior and patient race or ethnicity, except for Black patients who had lower odds of receiving treatment (OR, 0.77; P < .001).
IN PRACTICE:
“Given calls to rein in overutilization of end-of-life six to eight cancer therapies, our findings highlight an underappreciated area for further research: How treatment discontinuation before death is shaped by oncologists’ unique treatment propensities. Elucidating the reasons for this remarkable variability in oncologist treatment behavior could inform efforts to reduce end-of-life cancer treatment overutilization,” wrote the authors of the study.
SOURCE:
The study was led by Login S. George, PhD, Institute for Health, Health Care Policy and Aging Research, Rutgers University in New Brunswick, New Jersey. It was published online in Cancer.
LIMITATIONS:
The study’s reliance on SEER-Medicare data may limit the generalizability of the findings to patients with Medicare Advantage, private insurance, or Medicaid, as well as younger patients. The lack of data on patient preferences and other health characteristics could confound the results. The study focused on systemic therapies and may not be generalizable to other treatments such as clinical trial drugs, oral therapies, surgery, or radiation. The data from 2012 to 2017 may not reflect more recent trends in cancer treatment.
DISCLOSURES:
The study was supported by grants from the National Cancer Institute and the Rutgers Cancer Institute of New Jersey. George disclosed receiving grants from these organizations. Additional disclosures are noted in the original article.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article first appeared on Medscape.com.
Ancient Viruses in Our DNA Hold Clues to Cancer Treatment
according to a fascinating new study in Science Advances. Targeting these viral remnants still lingering in our DNA could lead to more effective cancer treatment with fewer side effects, the researchers said.
The study “gives a better understanding of how gene regulation can be impacted by these ancient retroviral sequences,” said Dixie Mager, PhD, scientist emeritus at the Terry Fox Laboratory at the British Columbia Cancer Research Institute, Vancouver, British Columbia, Canada. (Mager was not involved in the study.)
Long thought to be “junk” DNA with no biologic function, “endogenous retroviruses,” which have mutated over time and lost their ability to create the virus, are now known to regulate genes — allowing some genes to turn on and off. Research in recent years suggests they may play a role in diseases like cancer.
But scientists weren’t exactly sure what that role was, said senior study author Edward Chuong, PhD, a genome biologist at the University of Colorado Boulder.
Most studies have looked at whether endogenous retroviruses code for proteins that influence cancer. But these ancient viral strands usually don’t code for proteins at all.
Dr. Chuong took a different approach. Inspired by scientists who’ve studied how viral remnants regulate positive processes (immunity, brain development, or placenta development), he and his team explored whether some might regulate genes that, once activated, help cancer thrive.
Borrowing from epigenomic analysis data (data on molecules that alter gene expression) for 21 cancers mapped by the Cancer Genome Atlas, the researchers identified 19 virus-derived DNA sequences that bind to regulatory proteins more in cancer cells than in healthy cells. All of these could potentially act as gene regulators that promote cancer.
The researchers homed in on one sequence, called LTR10, because it showed especially high activity in several cancers, including lung and colorectal cancer. This DNA segment comes from a virus that entered our ancestors’ genome 30 million years ago, and it’s activated in a third of colorectal cancers.
Using the gene editing technology clustered regularly interspaced short palindromic repeats (CRISPR), Dr. Chuong’s team silenced LTR10 in colorectal cancer cells, altering the gene sequence so it couldn’t bind to regulatory proteins. Doing so dampened the activity of nearby cancer-promoting genes.
“They still behaved like cancer cells,” Dr. Chuong said. But “it made the cancer cells more susceptible to radiation. That would imply that the presence of that viral ‘switch’ actually helped those cancer cells survive radiation therapy.”
Previously, two studies had found that viral regulators play a role in promoting two types of cancer: Leukemia and prostate cancer. The new study shows these two cases weren’t flukes. All 21 cancers they looked at had at least one of those 19 viral elements, presumably working as cancer enhancers.
The study also identified what activates LTR10 to make it promote cancer. The culprit is a regulator protein called mitogen-activated protein (MAP) kinase, which is overactivated in about 40% of all human cancers.
Some cancer drugs — MAP kinase inhibitors — already target MAP kinase, and they’re often the first ones prescribed when a patient is diagnosed with cancer, Dr. Chuong said. As with many cancer treatments, doctors don’t know why they work, just that they do.
“By understanding the mechanisms in the cell, we might be able to make them work better or further optimize their treatment,” he said.
“MAP kinase inhibitors are really like a sledgehammer to the cell,” Dr. Chuong said — meaning they affect many cellular processes, not just those related to cancer.
“If we’re able to say that these viral switches are what’s important, then that could potentially help us develop a more targeted therapy that uses something like CRISPR to silence these viral elements,” he said. Or it could help providers choose a MAP kinase inhibitor from among the dozens available best suited to treat an individual patient and avoid side effects.
Still, whether the findings translate to real cancer patients remains to be seen. “It’s very, very hard to go the final step of showing in a patient that these actually make a difference in the cancer,” Dr. Mager said.
More lab research, human trials, and at least a few years will be needed before this discovery could help treat cancer. “Directly targeting these elements as a therapy would be at least 5 years out,” Dr. Chuong said, “partly because that application would rely on CRISPR epigenome editing technology that is still being developed for clinical use.”
A version of this article first appeared on Medscape.com.
according to a fascinating new study in Science Advances. Targeting these viral remnants still lingering in our DNA could lead to more effective cancer treatment with fewer side effects, the researchers said.
The study “gives a better understanding of how gene regulation can be impacted by these ancient retroviral sequences,” said Dixie Mager, PhD, scientist emeritus at the Terry Fox Laboratory at the British Columbia Cancer Research Institute, Vancouver, British Columbia, Canada. (Mager was not involved in the study.)
Long thought to be “junk” DNA with no biologic function, “endogenous retroviruses,” which have mutated over time and lost their ability to create the virus, are now known to regulate genes — allowing some genes to turn on and off. Research in recent years suggests they may play a role in diseases like cancer.
But scientists weren’t exactly sure what that role was, said senior study author Edward Chuong, PhD, a genome biologist at the University of Colorado Boulder.
Most studies have looked at whether endogenous retroviruses code for proteins that influence cancer. But these ancient viral strands usually don’t code for proteins at all.
Dr. Chuong took a different approach. Inspired by scientists who’ve studied how viral remnants regulate positive processes (immunity, brain development, or placenta development), he and his team explored whether some might regulate genes that, once activated, help cancer thrive.
Borrowing from epigenomic analysis data (data on molecules that alter gene expression) for 21 cancers mapped by the Cancer Genome Atlas, the researchers identified 19 virus-derived DNA sequences that bind to regulatory proteins more in cancer cells than in healthy cells. All of these could potentially act as gene regulators that promote cancer.
The researchers homed in on one sequence, called LTR10, because it showed especially high activity in several cancers, including lung and colorectal cancer. This DNA segment comes from a virus that entered our ancestors’ genome 30 million years ago, and it’s activated in a third of colorectal cancers.
Using the gene editing technology clustered regularly interspaced short palindromic repeats (CRISPR), Dr. Chuong’s team silenced LTR10 in colorectal cancer cells, altering the gene sequence so it couldn’t bind to regulatory proteins. Doing so dampened the activity of nearby cancer-promoting genes.
“They still behaved like cancer cells,” Dr. Chuong said. But “it made the cancer cells more susceptible to radiation. That would imply that the presence of that viral ‘switch’ actually helped those cancer cells survive radiation therapy.”
Previously, two studies had found that viral regulators play a role in promoting two types of cancer: Leukemia and prostate cancer. The new study shows these two cases weren’t flukes. All 21 cancers they looked at had at least one of those 19 viral elements, presumably working as cancer enhancers.
The study also identified what activates LTR10 to make it promote cancer. The culprit is a regulator protein called mitogen-activated protein (MAP) kinase, which is overactivated in about 40% of all human cancers.
Some cancer drugs — MAP kinase inhibitors — already target MAP kinase, and they’re often the first ones prescribed when a patient is diagnosed with cancer, Dr. Chuong said. As with many cancer treatments, doctors don’t know why they work, just that they do.
“By understanding the mechanisms in the cell, we might be able to make them work better or further optimize their treatment,” he said.
“MAP kinase inhibitors are really like a sledgehammer to the cell,” Dr. Chuong said — meaning they affect many cellular processes, not just those related to cancer.
“If we’re able to say that these viral switches are what’s important, then that could potentially help us develop a more targeted therapy that uses something like CRISPR to silence these viral elements,” he said. Or it could help providers choose a MAP kinase inhibitor from among the dozens available best suited to treat an individual patient and avoid side effects.
Still, whether the findings translate to real cancer patients remains to be seen. “It’s very, very hard to go the final step of showing in a patient that these actually make a difference in the cancer,” Dr. Mager said.
More lab research, human trials, and at least a few years will be needed before this discovery could help treat cancer. “Directly targeting these elements as a therapy would be at least 5 years out,” Dr. Chuong said, “partly because that application would rely on CRISPR epigenome editing technology that is still being developed for clinical use.”
A version of this article first appeared on Medscape.com.
according to a fascinating new study in Science Advances. Targeting these viral remnants still lingering in our DNA could lead to more effective cancer treatment with fewer side effects, the researchers said.
The study “gives a better understanding of how gene regulation can be impacted by these ancient retroviral sequences,” said Dixie Mager, PhD, scientist emeritus at the Terry Fox Laboratory at the British Columbia Cancer Research Institute, Vancouver, British Columbia, Canada. (Mager was not involved in the study.)
Long thought to be “junk” DNA with no biologic function, “endogenous retroviruses,” which have mutated over time and lost their ability to create the virus, are now known to regulate genes — allowing some genes to turn on and off. Research in recent years suggests they may play a role in diseases like cancer.
But scientists weren’t exactly sure what that role was, said senior study author Edward Chuong, PhD, a genome biologist at the University of Colorado Boulder.
Most studies have looked at whether endogenous retroviruses code for proteins that influence cancer. But these ancient viral strands usually don’t code for proteins at all.
Dr. Chuong took a different approach. Inspired by scientists who’ve studied how viral remnants regulate positive processes (immunity, brain development, or placenta development), he and his team explored whether some might regulate genes that, once activated, help cancer thrive.
Borrowing from epigenomic analysis data (data on molecules that alter gene expression) for 21 cancers mapped by the Cancer Genome Atlas, the researchers identified 19 virus-derived DNA sequences that bind to regulatory proteins more in cancer cells than in healthy cells. All of these could potentially act as gene regulators that promote cancer.
The researchers homed in on one sequence, called LTR10, because it showed especially high activity in several cancers, including lung and colorectal cancer. This DNA segment comes from a virus that entered our ancestors’ genome 30 million years ago, and it’s activated in a third of colorectal cancers.
Using the gene editing technology clustered regularly interspaced short palindromic repeats (CRISPR), Dr. Chuong’s team silenced LTR10 in colorectal cancer cells, altering the gene sequence so it couldn’t bind to regulatory proteins. Doing so dampened the activity of nearby cancer-promoting genes.
“They still behaved like cancer cells,” Dr. Chuong said. But “it made the cancer cells more susceptible to radiation. That would imply that the presence of that viral ‘switch’ actually helped those cancer cells survive radiation therapy.”
Previously, two studies had found that viral regulators play a role in promoting two types of cancer: Leukemia and prostate cancer. The new study shows these two cases weren’t flukes. All 21 cancers they looked at had at least one of those 19 viral elements, presumably working as cancer enhancers.
The study also identified what activates LTR10 to make it promote cancer. The culprit is a regulator protein called mitogen-activated protein (MAP) kinase, which is overactivated in about 40% of all human cancers.
Some cancer drugs — MAP kinase inhibitors — already target MAP kinase, and they’re often the first ones prescribed when a patient is diagnosed with cancer, Dr. Chuong said. As with many cancer treatments, doctors don’t know why they work, just that they do.
“By understanding the mechanisms in the cell, we might be able to make them work better or further optimize their treatment,” he said.
“MAP kinase inhibitors are really like a sledgehammer to the cell,” Dr. Chuong said — meaning they affect many cellular processes, not just those related to cancer.
“If we’re able to say that these viral switches are what’s important, then that could potentially help us develop a more targeted therapy that uses something like CRISPR to silence these viral elements,” he said. Or it could help providers choose a MAP kinase inhibitor from among the dozens available best suited to treat an individual patient and avoid side effects.
Still, whether the findings translate to real cancer patients remains to be seen. “It’s very, very hard to go the final step of showing in a patient that these actually make a difference in the cancer,” Dr. Mager said.
More lab research, human trials, and at least a few years will be needed before this discovery could help treat cancer. “Directly targeting these elements as a therapy would be at least 5 years out,” Dr. Chuong said, “partly because that application would rely on CRISPR epigenome editing technology that is still being developed for clinical use.”
A version of this article first appeared on Medscape.com.
FROM SCIENCE ADVANCES
Physician-Scientist Taps into Microbiome to Fight Cancer
The lowest point in the nascent career of Neelendu Dey, MD, helped seal his fate as a physician-scientist.
He had just started his first year as a resident at University of California, San Francisco. One of his patients was a 30-year-old woman who was dying of metastatic colorectal cancer. “I was in my mid-20s interacting with an individual just a few years older than I am, going through one of the most terrible health outcomes one could imagine,” Dr. Dey said.
He remembers asking the patient what he could do for her, how he could make her feel more comfortable. “That feeling of helplessness, particularly as we think about young people developing cancer, it really stuck with me through the years,” he said.
In an interview, he talked about his dual role as a physician and scientist, and how those two interests are guiding his research in precancerous conditions of the colon.
Cases like that of the young woman with colon cancer “really help drive the urgency of the work we do, and the research questions we ask, as we try to move the ball forward and help folks at earlier stages,” he said.
Q: Why did you choose GI?
When you think about what sorts of chronic diseases really impact your quality of life, gut health is one of the chief contributors among various aspects of health. And that really appealed to me — the ability to take someone who is essentially handicapped by a series of illnesses and symptoms that derive from the GI tract and enable them to return to the person they want to be, to be productive in the way that they want to be, and have a rewarding life.
As I thought about how I wanted to contribute to the future of medicine, one of the ways in which I’ve always thought that I would do that is through research. When I considered the fields that really appealed to me, both from that clinical standpoint and research standpoint, GI was one that really stood out. There has been a lot of exciting research going on in GI. My lab currently studies the microbiome, and I feel like this is an area in which we can contribute.
Q: What role does digestive health play in overall health?
Obviously, the direct answer is gut health is so critical in something like nutritional intake. Some GI symptoms, if your gut health has gone awry, can really be detrimental in terms of quality of life. But one less obvious role that digestive health plays is its long-term effects. We’re starting to appreciate that gut health, the gut microbiome, and gut immune education are probably long-term players. Some experiences in early life might shape our immunity in ways that have consequences for us much later in life. Whether we get early life antibiotics, for example, may potentially contribute to colorectal cancer down the line. Thinking about the long-term players is more challenging, but it’s also an appealing opportunity as we think about how we can shape medicine moving forward.
Q: What practice challenges have you faced in your career?
First, being a physician-scientist. It’s challenging to be either a physician alone or to be a researcher alone. And trying to do both includes the challenges of both individual worlds. It just takes more time to get all the prerequisite training. And second, there are just challenges with getting the opportunities to contribute in the ways that you want — to get the research funding, to get the papers out, things like that.
Q: Tell me about the work you’ve been doing in your lab to develop microbiome-based strategies for preventing and treating cancer.
The microbiome presents several opportunities when it comes to cancer prevention. One is identifying markers of cancer risk, or of general good health down the line. Some of those biomarkers could — potentially — feed directly into personalized risk assessment and maybe even inform a future screening strategy. The second opportunity the microbiome presents is if we identify a microbe that influences your cancer risk, can we then understand and exploit, or utilize, that mechanism to mitigate cancer risk in the future? Our lab has done work looking at subspecies levels of microbes that track with health or cancer. We’ve done some work to identify what these subspecies groupings are and have identified some links to certain precancerous changes in the colon. We think that there’s an opportunity here for future interventions.
Q: Have you published other papers?
We recently published another paper describing how some microbes can interact with a tumor suppressor gene and are influenced in a sex-biased manner to drive tumorigenesis in a mouse model. We think, based on what we’re seeing in human data, that there may be some relationships and we’re exploring that now as well.
Q: What is your vision for the future in GI, and in your career?
The vision that I have is to create clinical tools that can expand our reach and our effectiveness and cancer prevention. I think that there are opportunities for leveraging microbiome research to accomplish this. And one outcome I could imagine is leveraging some of these insights to expand noninvasive screening at even earlier ages than we do now. I mean, we just dialed back the recommended age for colonoscopy for average risk individuals to 45. But I could envision a future in which noninvasive screening starts earlier, in which the first stool-based tests that we deploy to assess personalized risk are used in the pediatric clinic.
Lightning Round
Texting or talking?
Talking
Favorite city in the United States besides the one you live in?
St. Louis
Cat or dog person?
Both
If you weren’t a GI, what would you be?
Musician
Best place you went on vacation?
Borneo
Favorite sport?
Soccer
Favorite ice cream?
Cashew-based salted caramel
What song do you have to sing along with when you hear it?
Sweet Child of Mine
Favorite movie or TV show?
25th Hour or Shawshank Redemption
Optimist or Pessimist?
Optimist
The lowest point in the nascent career of Neelendu Dey, MD, helped seal his fate as a physician-scientist.
He had just started his first year as a resident at University of California, San Francisco. One of his patients was a 30-year-old woman who was dying of metastatic colorectal cancer. “I was in my mid-20s interacting with an individual just a few years older than I am, going through one of the most terrible health outcomes one could imagine,” Dr. Dey said.
He remembers asking the patient what he could do for her, how he could make her feel more comfortable. “That feeling of helplessness, particularly as we think about young people developing cancer, it really stuck with me through the years,” he said.
In an interview, he talked about his dual role as a physician and scientist, and how those two interests are guiding his research in precancerous conditions of the colon.
Cases like that of the young woman with colon cancer “really help drive the urgency of the work we do, and the research questions we ask, as we try to move the ball forward and help folks at earlier stages,” he said.
Q: Why did you choose GI?
When you think about what sorts of chronic diseases really impact your quality of life, gut health is one of the chief contributors among various aspects of health. And that really appealed to me — the ability to take someone who is essentially handicapped by a series of illnesses and symptoms that derive from the GI tract and enable them to return to the person they want to be, to be productive in the way that they want to be, and have a rewarding life.
As I thought about how I wanted to contribute to the future of medicine, one of the ways in which I’ve always thought that I would do that is through research. When I considered the fields that really appealed to me, both from that clinical standpoint and research standpoint, GI was one that really stood out. There has been a lot of exciting research going on in GI. My lab currently studies the microbiome, and I feel like this is an area in which we can contribute.
Q: What role does digestive health play in overall health?
Obviously, the direct answer is gut health is so critical in something like nutritional intake. Some GI symptoms, if your gut health has gone awry, can really be detrimental in terms of quality of life. But one less obvious role that digestive health plays is its long-term effects. We’re starting to appreciate that gut health, the gut microbiome, and gut immune education are probably long-term players. Some experiences in early life might shape our immunity in ways that have consequences for us much later in life. Whether we get early life antibiotics, for example, may potentially contribute to colorectal cancer down the line. Thinking about the long-term players is more challenging, but it’s also an appealing opportunity as we think about how we can shape medicine moving forward.
Q: What practice challenges have you faced in your career?
First, being a physician-scientist. It’s challenging to be either a physician alone or to be a researcher alone. And trying to do both includes the challenges of both individual worlds. It just takes more time to get all the prerequisite training. And second, there are just challenges with getting the opportunities to contribute in the ways that you want — to get the research funding, to get the papers out, things like that.
Q: Tell me about the work you’ve been doing in your lab to develop microbiome-based strategies for preventing and treating cancer.
The microbiome presents several opportunities when it comes to cancer prevention. One is identifying markers of cancer risk, or of general good health down the line. Some of those biomarkers could — potentially — feed directly into personalized risk assessment and maybe even inform a future screening strategy. The second opportunity the microbiome presents is if we identify a microbe that influences your cancer risk, can we then understand and exploit, or utilize, that mechanism to mitigate cancer risk in the future? Our lab has done work looking at subspecies levels of microbes that track with health or cancer. We’ve done some work to identify what these subspecies groupings are and have identified some links to certain precancerous changes in the colon. We think that there’s an opportunity here for future interventions.
Q: Have you published other papers?
We recently published another paper describing how some microbes can interact with a tumor suppressor gene and are influenced in a sex-biased manner to drive tumorigenesis in a mouse model. We think, based on what we’re seeing in human data, that there may be some relationships and we’re exploring that now as well.
Q: What is your vision for the future in GI, and in your career?
The vision that I have is to create clinical tools that can expand our reach and our effectiveness and cancer prevention. I think that there are opportunities for leveraging microbiome research to accomplish this. And one outcome I could imagine is leveraging some of these insights to expand noninvasive screening at even earlier ages than we do now. I mean, we just dialed back the recommended age for colonoscopy for average risk individuals to 45. But I could envision a future in which noninvasive screening starts earlier, in which the first stool-based tests that we deploy to assess personalized risk are used in the pediatric clinic.
Lightning Round
Texting or talking?
Talking
Favorite city in the United States besides the one you live in?
St. Louis
Cat or dog person?
Both
If you weren’t a GI, what would you be?
Musician
Best place you went on vacation?
Borneo
Favorite sport?
Soccer
Favorite ice cream?
Cashew-based salted caramel
What song do you have to sing along with when you hear it?
Sweet Child of Mine
Favorite movie or TV show?
25th Hour or Shawshank Redemption
Optimist or Pessimist?
Optimist
The lowest point in the nascent career of Neelendu Dey, MD, helped seal his fate as a physician-scientist.
He had just started his first year as a resident at University of California, San Francisco. One of his patients was a 30-year-old woman who was dying of metastatic colorectal cancer. “I was in my mid-20s interacting with an individual just a few years older than I am, going through one of the most terrible health outcomes one could imagine,” Dr. Dey said.
He remembers asking the patient what he could do for her, how he could make her feel more comfortable. “That feeling of helplessness, particularly as we think about young people developing cancer, it really stuck with me through the years,” he said.
In an interview, he talked about his dual role as a physician and scientist, and how those two interests are guiding his research in precancerous conditions of the colon.
Cases like that of the young woman with colon cancer “really help drive the urgency of the work we do, and the research questions we ask, as we try to move the ball forward and help folks at earlier stages,” he said.
Q: Why did you choose GI?
When you think about what sorts of chronic diseases really impact your quality of life, gut health is one of the chief contributors among various aspects of health. And that really appealed to me — the ability to take someone who is essentially handicapped by a series of illnesses and symptoms that derive from the GI tract and enable them to return to the person they want to be, to be productive in the way that they want to be, and have a rewarding life.
As I thought about how I wanted to contribute to the future of medicine, one of the ways in which I’ve always thought that I would do that is through research. When I considered the fields that really appealed to me, both from that clinical standpoint and research standpoint, GI was one that really stood out. There has been a lot of exciting research going on in GI. My lab currently studies the microbiome, and I feel like this is an area in which we can contribute.
Q: What role does digestive health play in overall health?
Obviously, the direct answer is gut health is so critical in something like nutritional intake. Some GI symptoms, if your gut health has gone awry, can really be detrimental in terms of quality of life. But one less obvious role that digestive health plays is its long-term effects. We’re starting to appreciate that gut health, the gut microbiome, and gut immune education are probably long-term players. Some experiences in early life might shape our immunity in ways that have consequences for us much later in life. Whether we get early life antibiotics, for example, may potentially contribute to colorectal cancer down the line. Thinking about the long-term players is more challenging, but it’s also an appealing opportunity as we think about how we can shape medicine moving forward.
Q: What practice challenges have you faced in your career?
First, being a physician-scientist. It’s challenging to be either a physician alone or to be a researcher alone. And trying to do both includes the challenges of both individual worlds. It just takes more time to get all the prerequisite training. And second, there are just challenges with getting the opportunities to contribute in the ways that you want — to get the research funding, to get the papers out, things like that.
Q: Tell me about the work you’ve been doing in your lab to develop microbiome-based strategies for preventing and treating cancer.
The microbiome presents several opportunities when it comes to cancer prevention. One is identifying markers of cancer risk, or of general good health down the line. Some of those biomarkers could — potentially — feed directly into personalized risk assessment and maybe even inform a future screening strategy. The second opportunity the microbiome presents is if we identify a microbe that influences your cancer risk, can we then understand and exploit, or utilize, that mechanism to mitigate cancer risk in the future? Our lab has done work looking at subspecies levels of microbes that track with health or cancer. We’ve done some work to identify what these subspecies groupings are and have identified some links to certain precancerous changes in the colon. We think that there’s an opportunity here for future interventions.
Q: Have you published other papers?
We recently published another paper describing how some microbes can interact with a tumor suppressor gene and are influenced in a sex-biased manner to drive tumorigenesis in a mouse model. We think, based on what we’re seeing in human data, that there may be some relationships and we’re exploring that now as well.
Q: What is your vision for the future in GI, and in your career?
The vision that I have is to create clinical tools that can expand our reach and our effectiveness and cancer prevention. I think that there are opportunities for leveraging microbiome research to accomplish this. And one outcome I could imagine is leveraging some of these insights to expand noninvasive screening at even earlier ages than we do now. I mean, we just dialed back the recommended age for colonoscopy for average risk individuals to 45. But I could envision a future in which noninvasive screening starts earlier, in which the first stool-based tests that we deploy to assess personalized risk are used in the pediatric clinic.
Lightning Round
Texting or talking?
Talking
Favorite city in the United States besides the one you live in?
St. Louis
Cat or dog person?
Both
If you weren’t a GI, what would you be?
Musician
Best place you went on vacation?
Borneo
Favorite sport?
Soccer
Favorite ice cream?
Cashew-based salted caramel
What song do you have to sing along with when you hear it?
Sweet Child of Mine
Favorite movie or TV show?
25th Hour or Shawshank Redemption
Optimist or Pessimist?
Optimist
Breakthrough Blood Test for Colorectal Cancer Gets Green Light
The FDA on July 29 approved the test, called Shield, which can accurately detect tumors in the colon or rectum about 87% of the time when the cancer is in treatable early stages. The approval was announced July 29 by the test’s maker, Guardant Health, and comes just months after promising clinical trial results were published in The New England Journal of Medicine.
Colorectal cancer is among the most common types of cancer diagnosed in the United States each year, along with being one of the leading causes of cancer deaths. The condition is treatable in early stages, but about 1 in 3 people don’t stay up to date on regular screenings, which should begin at age 45.
The simplicity of a blood test could make it more likely for people to be screened for and, ultimately, survive the disease. Other primary screening options include feces-based tests or colonoscopy. The 5-year survival rate for colorectal cancer is 64%.
While highly accurate at detecting DNA shed by tumors during treatable stages of colorectal cancer, the Shield test was not as effective at detecting precancerous areas of tissue, which are typically removed after being detected.
In its news release, Guardant Health officials said they anticipate the test to be covered under Medicare. The out-of-pocket cost for people whose insurance does not cover the test has not yet been announced. The test is expected to be available by next week, The New York Times reported.
If someone’s Shield test comes back positive, the person would then get more tests to confirm the result. Shield was shown in trials to have a 10% false positive rate.
“I was in for a routine physical, and my doctor asked when I had my last colonoscopy,” said John Gormly, a 77-year-old business executive in Newport Beach, California, according to a Guardant Health news release. “I said it’s been a long time, so he offered to give me the Shield blood test. A few days later, the result came back positive, so he referred me for a colonoscopy. It turned out I had stage II colon cancer. The tumor was removed, and I recovered very quickly. Thank God I had taken that blood test.”
A version of this article appeared on WebMD.com.
The FDA on July 29 approved the test, called Shield, which can accurately detect tumors in the colon or rectum about 87% of the time when the cancer is in treatable early stages. The approval was announced July 29 by the test’s maker, Guardant Health, and comes just months after promising clinical trial results were published in The New England Journal of Medicine.
Colorectal cancer is among the most common types of cancer diagnosed in the United States each year, along with being one of the leading causes of cancer deaths. The condition is treatable in early stages, but about 1 in 3 people don’t stay up to date on regular screenings, which should begin at age 45.
The simplicity of a blood test could make it more likely for people to be screened for and, ultimately, survive the disease. Other primary screening options include feces-based tests or colonoscopy. The 5-year survival rate for colorectal cancer is 64%.
While highly accurate at detecting DNA shed by tumors during treatable stages of colorectal cancer, the Shield test was not as effective at detecting precancerous areas of tissue, which are typically removed after being detected.
In its news release, Guardant Health officials said they anticipate the test to be covered under Medicare. The out-of-pocket cost for people whose insurance does not cover the test has not yet been announced. The test is expected to be available by next week, The New York Times reported.
If someone’s Shield test comes back positive, the person would then get more tests to confirm the result. Shield was shown in trials to have a 10% false positive rate.
“I was in for a routine physical, and my doctor asked when I had my last colonoscopy,” said John Gormly, a 77-year-old business executive in Newport Beach, California, according to a Guardant Health news release. “I said it’s been a long time, so he offered to give me the Shield blood test. A few days later, the result came back positive, so he referred me for a colonoscopy. It turned out I had stage II colon cancer. The tumor was removed, and I recovered very quickly. Thank God I had taken that blood test.”
A version of this article appeared on WebMD.com.
The FDA on July 29 approved the test, called Shield, which can accurately detect tumors in the colon or rectum about 87% of the time when the cancer is in treatable early stages. The approval was announced July 29 by the test’s maker, Guardant Health, and comes just months after promising clinical trial results were published in The New England Journal of Medicine.
Colorectal cancer is among the most common types of cancer diagnosed in the United States each year, along with being one of the leading causes of cancer deaths. The condition is treatable in early stages, but about 1 in 3 people don’t stay up to date on regular screenings, which should begin at age 45.
The simplicity of a blood test could make it more likely for people to be screened for and, ultimately, survive the disease. Other primary screening options include feces-based tests or colonoscopy. The 5-year survival rate for colorectal cancer is 64%.
While highly accurate at detecting DNA shed by tumors during treatable stages of colorectal cancer, the Shield test was not as effective at detecting precancerous areas of tissue, which are typically removed after being detected.
In its news release, Guardant Health officials said they anticipate the test to be covered under Medicare. The out-of-pocket cost for people whose insurance does not cover the test has not yet been announced. The test is expected to be available by next week, The New York Times reported.
If someone’s Shield test comes back positive, the person would then get more tests to confirm the result. Shield was shown in trials to have a 10% false positive rate.
“I was in for a routine physical, and my doctor asked when I had my last colonoscopy,” said John Gormly, a 77-year-old business executive in Newport Beach, California, according to a Guardant Health news release. “I said it’s been a long time, so he offered to give me the Shield blood test. A few days later, the result came back positive, so he referred me for a colonoscopy. It turned out I had stage II colon cancer. The tumor was removed, and I recovered very quickly. Thank God I had taken that blood test.”
A version of this article appeared on WebMD.com.
FDA Calls AstraZeneca’s NSCLC Trial Design Into Question
The trial in question, AEGEAN, investigated perioperative durvalumab for resectable NSCLC tumors across 802 patients. Patients without EGFR or ALK mutations were randomly assigned to receive durvalumab before surgery alongside platinum-containing chemotherapy and after surgery for a year as monotherapy or to receive chemotherapy and surgery alone.
Patients receiving durvalumab demonstrated better event-free survival at 1 year (73.4% vs 64.5% without durvalumab) and a better pathologic complete response rate (17.2% vs 4.3% without). Currently, AstraZeneca is seeking to add the indication for durvalumab to those the agent already has.
However, at the July 25 ODAC meeting, the committee explained that the AEGEAN trial design makes it impossible to tell whether patients benefited from durvalumab before surgery, after it, or at both points.
Mounting evidence, including from AstraZeneca’s own studies, suggests that the benefit of immune checkpoint inhibitors, such as durvalumab, comes before surgery. That means prescribing durvalumab after surgery could be exposing patients to serious side effects and financial toxicity, with potentially no clinical benefit, “magnifying the risk of potential overtreatment,” the committee cautioned.
When AEGEAN was being designed in 2018, FDA requested that AstraZeneca address the uncertainty surrounding when to use durvalumab by including separate neoadjuvant and adjuvant arms, or at least an arm where patients were treated with neoadjuvant durvalumab alone to compare with treatment both before and after surgery.
The company didn’t follow through and, during the July 25 meeting, the committee wanted answers. “Why did you not comply with this?” asked ODAC committee acting chair Daniel Spratt, MD, a radiation oncologist at Case Western Reserve University in Cleveland, Ohio.
AstraZeneca personnel explained that doing so would have required many more subjects, made the trial more expensive, and added about 2 years to AEGEAN.
One speaker noted that the company, which makes more than $4 billion a year on durvalumab, would have taken about 2 days to recoup that added cost. Others wondered whether the motive was to sell durvalumab for as long as possible across a patient’s course of treatment.
Perhaps the biggest reason the company ignored the request is that “it wasn’t our understanding at that time that this was a barrier to approval,” an AstraZeneca regulatory affairs specialist said.
To this end, the agency asked its advisory panel to vote on whether it should require — instead of simply request, as it did with AstraZeneca — companies to prove that patients need immunotherapy both before and after surgery in resectable NSCLC.
The 11-member panel voted unanimously that it should make this a requirement, and several members said it should do so in other cancers as well.
However, when the agency asked whether durvalumab’s resectable NSCLC approval should be delayed until AstraZeneca conducts a trial to answer the neoadjuvant vs adjuvant question, the panel members didn’t think so.
The consensus was that because AEGEAN showed a decent benefit, patients and physicians should have it as an option, and approval shouldn’t be delayed. The panel said that the bigger question about the benefit of maintenance therapy should be left to future studies.
FDA usually follows the advice of its advisory panels.
A version of this article appeared on Medscape.com.
The trial in question, AEGEAN, investigated perioperative durvalumab for resectable NSCLC tumors across 802 patients. Patients without EGFR or ALK mutations were randomly assigned to receive durvalumab before surgery alongside platinum-containing chemotherapy and after surgery for a year as monotherapy or to receive chemotherapy and surgery alone.
Patients receiving durvalumab demonstrated better event-free survival at 1 year (73.4% vs 64.5% without durvalumab) and a better pathologic complete response rate (17.2% vs 4.3% without). Currently, AstraZeneca is seeking to add the indication for durvalumab to those the agent already has.
However, at the July 25 ODAC meeting, the committee explained that the AEGEAN trial design makes it impossible to tell whether patients benefited from durvalumab before surgery, after it, or at both points.
Mounting evidence, including from AstraZeneca’s own studies, suggests that the benefit of immune checkpoint inhibitors, such as durvalumab, comes before surgery. That means prescribing durvalumab after surgery could be exposing patients to serious side effects and financial toxicity, with potentially no clinical benefit, “magnifying the risk of potential overtreatment,” the committee cautioned.
When AEGEAN was being designed in 2018, FDA requested that AstraZeneca address the uncertainty surrounding when to use durvalumab by including separate neoadjuvant and adjuvant arms, or at least an arm where patients were treated with neoadjuvant durvalumab alone to compare with treatment both before and after surgery.
The company didn’t follow through and, during the July 25 meeting, the committee wanted answers. “Why did you not comply with this?” asked ODAC committee acting chair Daniel Spratt, MD, a radiation oncologist at Case Western Reserve University in Cleveland, Ohio.
AstraZeneca personnel explained that doing so would have required many more subjects, made the trial more expensive, and added about 2 years to AEGEAN.
One speaker noted that the company, which makes more than $4 billion a year on durvalumab, would have taken about 2 days to recoup that added cost. Others wondered whether the motive was to sell durvalumab for as long as possible across a patient’s course of treatment.
Perhaps the biggest reason the company ignored the request is that “it wasn’t our understanding at that time that this was a barrier to approval,” an AstraZeneca regulatory affairs specialist said.
To this end, the agency asked its advisory panel to vote on whether it should require — instead of simply request, as it did with AstraZeneca — companies to prove that patients need immunotherapy both before and after surgery in resectable NSCLC.
The 11-member panel voted unanimously that it should make this a requirement, and several members said it should do so in other cancers as well.
However, when the agency asked whether durvalumab’s resectable NSCLC approval should be delayed until AstraZeneca conducts a trial to answer the neoadjuvant vs adjuvant question, the panel members didn’t think so.
The consensus was that because AEGEAN showed a decent benefit, patients and physicians should have it as an option, and approval shouldn’t be delayed. The panel said that the bigger question about the benefit of maintenance therapy should be left to future studies.
FDA usually follows the advice of its advisory panels.
A version of this article appeared on Medscape.com.
The trial in question, AEGEAN, investigated perioperative durvalumab for resectable NSCLC tumors across 802 patients. Patients without EGFR or ALK mutations were randomly assigned to receive durvalumab before surgery alongside platinum-containing chemotherapy and after surgery for a year as monotherapy or to receive chemotherapy and surgery alone.
Patients receiving durvalumab demonstrated better event-free survival at 1 year (73.4% vs 64.5% without durvalumab) and a better pathologic complete response rate (17.2% vs 4.3% without). Currently, AstraZeneca is seeking to add the indication for durvalumab to those the agent already has.
However, at the July 25 ODAC meeting, the committee explained that the AEGEAN trial design makes it impossible to tell whether patients benefited from durvalumab before surgery, after it, or at both points.
Mounting evidence, including from AstraZeneca’s own studies, suggests that the benefit of immune checkpoint inhibitors, such as durvalumab, comes before surgery. That means prescribing durvalumab after surgery could be exposing patients to serious side effects and financial toxicity, with potentially no clinical benefit, “magnifying the risk of potential overtreatment,” the committee cautioned.
When AEGEAN was being designed in 2018, FDA requested that AstraZeneca address the uncertainty surrounding when to use durvalumab by including separate neoadjuvant and adjuvant arms, or at least an arm where patients were treated with neoadjuvant durvalumab alone to compare with treatment both before and after surgery.
The company didn’t follow through and, during the July 25 meeting, the committee wanted answers. “Why did you not comply with this?” asked ODAC committee acting chair Daniel Spratt, MD, a radiation oncologist at Case Western Reserve University in Cleveland, Ohio.
AstraZeneca personnel explained that doing so would have required many more subjects, made the trial more expensive, and added about 2 years to AEGEAN.
One speaker noted that the company, which makes more than $4 billion a year on durvalumab, would have taken about 2 days to recoup that added cost. Others wondered whether the motive was to sell durvalumab for as long as possible across a patient’s course of treatment.
Perhaps the biggest reason the company ignored the request is that “it wasn’t our understanding at that time that this was a barrier to approval,” an AstraZeneca regulatory affairs specialist said.
To this end, the agency asked its advisory panel to vote on whether it should require — instead of simply request, as it did with AstraZeneca — companies to prove that patients need immunotherapy both before and after surgery in resectable NSCLC.
The 11-member panel voted unanimously that it should make this a requirement, and several members said it should do so in other cancers as well.
However, when the agency asked whether durvalumab’s resectable NSCLC approval should be delayed until AstraZeneca conducts a trial to answer the neoadjuvant vs adjuvant question, the panel members didn’t think so.
The consensus was that because AEGEAN showed a decent benefit, patients and physicians should have it as an option, and approval shouldn’t be delayed. The panel said that the bigger question about the benefit of maintenance therapy should be left to future studies.
FDA usually follows the advice of its advisory panels.
A version of this article appeared on Medscape.com.
Which Patients With Early TNBC Can Avoid Chemotherapy?
TOPLINE:
which suggest that stromal TILs could be a useful biomarker to optimize treatment decisions in this patient population.
METHODOLOGY:
- The absolute benefit of chemotherapy remains unclear among patients with stage I TNBC. High levels of stromal TILs, a promising biomarker, have been linked to better survival in patients with TNBC, but data focused on stage I disease are lacking.
- In the current analysis, researchers identified a cohort of 1041 women (mean age at diagnosis, 64.4 years) from the Netherlands Cancer Registry with stage I TNBC who had an available TIL score and had undergone a lumpectomy or a mastectomy but had not received neoadjuvant or adjuvant chemotherapy.
- Patients’ clinical data were matched to their corresponding pathologic data provided by the Dutch Pathology Registry, and a pathologist blinded to outcomes scored stromal TIL levels according to the International Immuno-Oncology Biomarker Working Group guidelines.
- The primary endpoint was breast cancer–specific survival at prespecified stromal TIL cutoffs of 30%, 50%, and 75%. Secondary outcomes included specific survival by pathologic tumor stage and overall survival.
TAKEAWAY:
- Overall, 8.6% of women had a pT1a tumor, 38.7% had a pT1b tumor, and 52.6% had a pT1c tumor. In the cohort, 25.6% of patients had stromal TIL levels of 30% or higher, 19.5% had levels of 50% or higher, and 13.5% had levels of 75% or higher.
- Over a median follow-up of 11.4 years, 335 patients died, 107 (32%) of whom died from breast cancer. Patients with smaller tumors (pT1abNO) had better survival outcomes than those with larger tumors (pT1cNO) — a 10-year breast cancer–specific survival of 92% vs 86%, respectively.
- In the overall cohort, stromal TIL levels of 30% or higher were associated with better breast cancer–specific survival than those with stromal TIL levels below 30% (96% vs 87%; hazard ratio [HR], 0.45). Stromal TIL levels of 50% or greater were also associated with better 10-year breast cancer–specific survival than those with levels below 50% (92% vs 88%; HR, 0.59). A similar pattern was observed for stromal TIL levels and overall survival.
- In patients with pT1c tumors, the 10-year breast cancer–specific survival among those with stromal TIL levels of 30% or higher was 95% vs 83% for levels below the 30% cutoff (HR, 0.24). Similarly, the 10-year breast cancer–specific survival for those in the 50% or higher group was 95% vs 84% for levels below that cutoff (HR, 0.27). The 10-year breast cancer–specific survival improved to 98% among patients with stromal TIL levels of 75% or higher (HR, 0.09).
IN PRACTICE:
The results supported the establishment of “treatment-optimization clinical trials in patients with stage I TNBC, using [stromal] TIL level as an integral biomarker to prospectively confirm the observed excellent survival when neoadjuvant or adjuvant chemotherapy is not administered,” the authors wrote. Assessing stromal TILs is also “inexpensive,” the authors added.
SOURCE:
The research, conducted by Marleen Kok, MD, PhD, Department of Medical Oncology, the Netherlands Cancer Institute, Amsterdam, and colleagues, was published online in JAMA Oncology.
LIMITATIONS:
The authors noted that the study was limited by its observational nature. The patients were drawn from a larger cohort, about half of whom received adjuvant chemotherapy, and the patients who did not receive chemotherapy may have had favorable tumor characteristics. There were also no data on BRCA1 or BRCA2 germline mutation status and recurrences and/or distant metastases. The database did not include data on patient ethnicity because most Dutch patients were White.
DISCLOSURES:
Research at the Netherlands Cancer Institute was supported by institutional grants from the Dutch Cancer Society and the Dutch Ministry of Health, Welfare and Sport. Dr. Kok declared financial relationships with several organizations including Gilead and Domain Therapeutics, as well as institutional grants from AstraZeneca, BMS, and Roche. Other authors also declared numerous financial relationships for themselves and their institutions with pharmaceutical companies.
A version of this article first appeared on Medscape.com.
TOPLINE:
which suggest that stromal TILs could be a useful biomarker to optimize treatment decisions in this patient population.
METHODOLOGY:
- The absolute benefit of chemotherapy remains unclear among patients with stage I TNBC. High levels of stromal TILs, a promising biomarker, have been linked to better survival in patients with TNBC, but data focused on stage I disease are lacking.
- In the current analysis, researchers identified a cohort of 1041 women (mean age at diagnosis, 64.4 years) from the Netherlands Cancer Registry with stage I TNBC who had an available TIL score and had undergone a lumpectomy or a mastectomy but had not received neoadjuvant or adjuvant chemotherapy.
- Patients’ clinical data were matched to their corresponding pathologic data provided by the Dutch Pathology Registry, and a pathologist blinded to outcomes scored stromal TIL levels according to the International Immuno-Oncology Biomarker Working Group guidelines.
- The primary endpoint was breast cancer–specific survival at prespecified stromal TIL cutoffs of 30%, 50%, and 75%. Secondary outcomes included specific survival by pathologic tumor stage and overall survival.
TAKEAWAY:
- Overall, 8.6% of women had a pT1a tumor, 38.7% had a pT1b tumor, and 52.6% had a pT1c tumor. In the cohort, 25.6% of patients had stromal TIL levels of 30% or higher, 19.5% had levels of 50% or higher, and 13.5% had levels of 75% or higher.
- Over a median follow-up of 11.4 years, 335 patients died, 107 (32%) of whom died from breast cancer. Patients with smaller tumors (pT1abNO) had better survival outcomes than those with larger tumors (pT1cNO) — a 10-year breast cancer–specific survival of 92% vs 86%, respectively.
- In the overall cohort, stromal TIL levels of 30% or higher were associated with better breast cancer–specific survival than those with stromal TIL levels below 30% (96% vs 87%; hazard ratio [HR], 0.45). Stromal TIL levels of 50% or greater were also associated with better 10-year breast cancer–specific survival than those with levels below 50% (92% vs 88%; HR, 0.59). A similar pattern was observed for stromal TIL levels and overall survival.
- In patients with pT1c tumors, the 10-year breast cancer–specific survival among those with stromal TIL levels of 30% or higher was 95% vs 83% for levels below the 30% cutoff (HR, 0.24). Similarly, the 10-year breast cancer–specific survival for those in the 50% or higher group was 95% vs 84% for levels below that cutoff (HR, 0.27). The 10-year breast cancer–specific survival improved to 98% among patients with stromal TIL levels of 75% or higher (HR, 0.09).
IN PRACTICE:
The results supported the establishment of “treatment-optimization clinical trials in patients with stage I TNBC, using [stromal] TIL level as an integral biomarker to prospectively confirm the observed excellent survival when neoadjuvant or adjuvant chemotherapy is not administered,” the authors wrote. Assessing stromal TILs is also “inexpensive,” the authors added.
SOURCE:
The research, conducted by Marleen Kok, MD, PhD, Department of Medical Oncology, the Netherlands Cancer Institute, Amsterdam, and colleagues, was published online in JAMA Oncology.
LIMITATIONS:
The authors noted that the study was limited by its observational nature. The patients were drawn from a larger cohort, about half of whom received adjuvant chemotherapy, and the patients who did not receive chemotherapy may have had favorable tumor characteristics. There were also no data on BRCA1 or BRCA2 germline mutation status and recurrences and/or distant metastases. The database did not include data on patient ethnicity because most Dutch patients were White.
DISCLOSURES:
Research at the Netherlands Cancer Institute was supported by institutional grants from the Dutch Cancer Society and the Dutch Ministry of Health, Welfare and Sport. Dr. Kok declared financial relationships with several organizations including Gilead and Domain Therapeutics, as well as institutional grants from AstraZeneca, BMS, and Roche. Other authors also declared numerous financial relationships for themselves and their institutions with pharmaceutical companies.
A version of this article first appeared on Medscape.com.
TOPLINE:
which suggest that stromal TILs could be a useful biomarker to optimize treatment decisions in this patient population.
METHODOLOGY:
- The absolute benefit of chemotherapy remains unclear among patients with stage I TNBC. High levels of stromal TILs, a promising biomarker, have been linked to better survival in patients with TNBC, but data focused on stage I disease are lacking.
- In the current analysis, researchers identified a cohort of 1041 women (mean age at diagnosis, 64.4 years) from the Netherlands Cancer Registry with stage I TNBC who had an available TIL score and had undergone a lumpectomy or a mastectomy but had not received neoadjuvant or adjuvant chemotherapy.
- Patients’ clinical data were matched to their corresponding pathologic data provided by the Dutch Pathology Registry, and a pathologist blinded to outcomes scored stromal TIL levels according to the International Immuno-Oncology Biomarker Working Group guidelines.
- The primary endpoint was breast cancer–specific survival at prespecified stromal TIL cutoffs of 30%, 50%, and 75%. Secondary outcomes included specific survival by pathologic tumor stage and overall survival.
TAKEAWAY:
- Overall, 8.6% of women had a pT1a tumor, 38.7% had a pT1b tumor, and 52.6% had a pT1c tumor. In the cohort, 25.6% of patients had stromal TIL levels of 30% or higher, 19.5% had levels of 50% or higher, and 13.5% had levels of 75% or higher.
- Over a median follow-up of 11.4 years, 335 patients died, 107 (32%) of whom died from breast cancer. Patients with smaller tumors (pT1abNO) had better survival outcomes than those with larger tumors (pT1cNO) — a 10-year breast cancer–specific survival of 92% vs 86%, respectively.
- In the overall cohort, stromal TIL levels of 30% or higher were associated with better breast cancer–specific survival than those with stromal TIL levels below 30% (96% vs 87%; hazard ratio [HR], 0.45). Stromal TIL levels of 50% or greater were also associated with better 10-year breast cancer–specific survival than those with levels below 50% (92% vs 88%; HR, 0.59). A similar pattern was observed for stromal TIL levels and overall survival.
- In patients with pT1c tumors, the 10-year breast cancer–specific survival among those with stromal TIL levels of 30% or higher was 95% vs 83% for levels below the 30% cutoff (HR, 0.24). Similarly, the 10-year breast cancer–specific survival for those in the 50% or higher group was 95% vs 84% for levels below that cutoff (HR, 0.27). The 10-year breast cancer–specific survival improved to 98% among patients with stromal TIL levels of 75% or higher (HR, 0.09).
IN PRACTICE:
The results supported the establishment of “treatment-optimization clinical trials in patients with stage I TNBC, using [stromal] TIL level as an integral biomarker to prospectively confirm the observed excellent survival when neoadjuvant or adjuvant chemotherapy is not administered,” the authors wrote. Assessing stromal TILs is also “inexpensive,” the authors added.
SOURCE:
The research, conducted by Marleen Kok, MD, PhD, Department of Medical Oncology, the Netherlands Cancer Institute, Amsterdam, and colleagues, was published online in JAMA Oncology.
LIMITATIONS:
The authors noted that the study was limited by its observational nature. The patients were drawn from a larger cohort, about half of whom received adjuvant chemotherapy, and the patients who did not receive chemotherapy may have had favorable tumor characteristics. There were also no data on BRCA1 or BRCA2 germline mutation status and recurrences and/or distant metastases. The database did not include data on patient ethnicity because most Dutch patients were White.
DISCLOSURES:
Research at the Netherlands Cancer Institute was supported by institutional grants from the Dutch Cancer Society and the Dutch Ministry of Health, Welfare and Sport. Dr. Kok declared financial relationships with several organizations including Gilead and Domain Therapeutics, as well as institutional grants from AstraZeneca, BMS, and Roche. Other authors also declared numerous financial relationships for themselves and their institutions with pharmaceutical companies.
A version of this article first appeared on Medscape.com.
Baseline Bone Pain Predicts Survival in Metastatic Hormone-Sensitive Prostate Cancer
TOPLINE:
METHODOLOGY:
- Prostate cancer often metastasizes to the bones, leading to pain and a reduced quality of life. While the relationship between bone pain and overall survival in metastatic, castration-resistant prostate cancer is well-documented, its impact in metastatic hormone-sensitive prostate cancer is less clear.
- Researchers conducted a post hoc secondary analysis using data from the SWOG-1216 phase 3 randomized clinical trial, which included 1279 men diagnosed with metastatic hormone-sensitive prostate cancer from 248 centers across the United States. Patients had received androgen deprivation therapy either with orteronel or bicalutamide.
- Among the 1197 patients (median age, 67.6 years) with data on bone pain included in the secondary analysis, 301 (23.5%) reported bone pain at baseline.
- The primary outcome was overall survival; secondary outcomes included progression-free survival and prostate-specific antigen response.
TAKEAWAY:
- The median overall survival for patients with baseline bone pain was 3.9 years compared with not reached (95% CI, 6.6 years to not reached) for those without bone pain at a median follow-up of 4 years (adjusted hazard ratio [aHR], 1.66; P < .001).
- Similarly, patients with bone pain had a shorter progression-free survival vs those without bone pain (median, 1.3 years vs 3.7 years; aHR, 1.46; P < .001).
- The complete prostate-specific antigen response rate at 7 months was also lower for patients with baseline bone pain (46.3% vs 66.3%; P < .001).
IN PRACTICE:
Patients with metastatic hormone-sensitive prostate cancer “with baseline bone pain had worse survival outcomes than those without baseline bone pain,” the authors wrote. “These results highlight the need to consider bone pain in prognostic modeling, treatment selection, patient monitoring, and follow-up and suggest prioritizing these patients for clinical trials and immediate systemic treatment initiation.”
SOURCE:
The study, led by Georges Gebrael, MD, Huntsman Cancer Institute at the University of Utah, Salt Lake City, Utah, was published online in JAMA Network Open.
LIMITATIONS:
The post hoc design may introduce bias. Orteronel failed to receive regulatory approval, which may affect the generalizability of the findings. In addition, the study did not account for synchronous vs metachronous disease status, a known established prognostic factor.
DISCLOSURES:
The study was funded by the National Institutes of Health/National Cancer Institute and Millennium Pharmaceuticals (Takeda Oncology Company). Several authors declared ties with various sources.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article first appeared on Medscape.com.
TOPLINE:
METHODOLOGY:
- Prostate cancer often metastasizes to the bones, leading to pain and a reduced quality of life. While the relationship between bone pain and overall survival in metastatic, castration-resistant prostate cancer is well-documented, its impact in metastatic hormone-sensitive prostate cancer is less clear.
- Researchers conducted a post hoc secondary analysis using data from the SWOG-1216 phase 3 randomized clinical trial, which included 1279 men diagnosed with metastatic hormone-sensitive prostate cancer from 248 centers across the United States. Patients had received androgen deprivation therapy either with orteronel or bicalutamide.
- Among the 1197 patients (median age, 67.6 years) with data on bone pain included in the secondary analysis, 301 (23.5%) reported bone pain at baseline.
- The primary outcome was overall survival; secondary outcomes included progression-free survival and prostate-specific antigen response.
TAKEAWAY:
- The median overall survival for patients with baseline bone pain was 3.9 years compared with not reached (95% CI, 6.6 years to not reached) for those without bone pain at a median follow-up of 4 years (adjusted hazard ratio [aHR], 1.66; P < .001).
- Similarly, patients with bone pain had a shorter progression-free survival vs those without bone pain (median, 1.3 years vs 3.7 years; aHR, 1.46; P < .001).
- The complete prostate-specific antigen response rate at 7 months was also lower for patients with baseline bone pain (46.3% vs 66.3%; P < .001).
IN PRACTICE:
Patients with metastatic hormone-sensitive prostate cancer “with baseline bone pain had worse survival outcomes than those without baseline bone pain,” the authors wrote. “These results highlight the need to consider bone pain in prognostic modeling, treatment selection, patient monitoring, and follow-up and suggest prioritizing these patients for clinical trials and immediate systemic treatment initiation.”
SOURCE:
The study, led by Georges Gebrael, MD, Huntsman Cancer Institute at the University of Utah, Salt Lake City, Utah, was published online in JAMA Network Open.
LIMITATIONS:
The post hoc design may introduce bias. Orteronel failed to receive regulatory approval, which may affect the generalizability of the findings. In addition, the study did not account for synchronous vs metachronous disease status, a known established prognostic factor.
DISCLOSURES:
The study was funded by the National Institutes of Health/National Cancer Institute and Millennium Pharmaceuticals (Takeda Oncology Company). Several authors declared ties with various sources.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article first appeared on Medscape.com.
TOPLINE:
METHODOLOGY:
- Prostate cancer often metastasizes to the bones, leading to pain and a reduced quality of life. While the relationship between bone pain and overall survival in metastatic, castration-resistant prostate cancer is well-documented, its impact in metastatic hormone-sensitive prostate cancer is less clear.
- Researchers conducted a post hoc secondary analysis using data from the SWOG-1216 phase 3 randomized clinical trial, which included 1279 men diagnosed with metastatic hormone-sensitive prostate cancer from 248 centers across the United States. Patients had received androgen deprivation therapy either with orteronel or bicalutamide.
- Among the 1197 patients (median age, 67.6 years) with data on bone pain included in the secondary analysis, 301 (23.5%) reported bone pain at baseline.
- The primary outcome was overall survival; secondary outcomes included progression-free survival and prostate-specific antigen response.
TAKEAWAY:
- The median overall survival for patients with baseline bone pain was 3.9 years compared with not reached (95% CI, 6.6 years to not reached) for those without bone pain at a median follow-up of 4 years (adjusted hazard ratio [aHR], 1.66; P < .001).
- Similarly, patients with bone pain had a shorter progression-free survival vs those without bone pain (median, 1.3 years vs 3.7 years; aHR, 1.46; P < .001).
- The complete prostate-specific antigen response rate at 7 months was also lower for patients with baseline bone pain (46.3% vs 66.3%; P < .001).
IN PRACTICE:
Patients with metastatic hormone-sensitive prostate cancer “with baseline bone pain had worse survival outcomes than those without baseline bone pain,” the authors wrote. “These results highlight the need to consider bone pain in prognostic modeling, treatment selection, patient monitoring, and follow-up and suggest prioritizing these patients for clinical trials and immediate systemic treatment initiation.”
SOURCE:
The study, led by Georges Gebrael, MD, Huntsman Cancer Institute at the University of Utah, Salt Lake City, Utah, was published online in JAMA Network Open.
LIMITATIONS:
The post hoc design may introduce bias. Orteronel failed to receive regulatory approval, which may affect the generalizability of the findings. In addition, the study did not account for synchronous vs metachronous disease status, a known established prognostic factor.
DISCLOSURES:
The study was funded by the National Institutes of Health/National Cancer Institute and Millennium Pharmaceuticals (Takeda Oncology Company). Several authors declared ties with various sources.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article first appeared on Medscape.com.
Fed Worker Health Plans Ban Maximizers and Copay Accumulators: Why Not for the Rest of the US?
The escalating costs of medications and the prevalence of medical bankruptcy in our country have drawn criticism from governments, regulators, and the media. Federal and state governments are exploring various strategies to mitigate this issue, including the Inflation Reduction Act (IRA) for drug price negotiations and the establishment of state Pharmaceutical Drug Affordability Boards (PDABs). However, it’s uncertain whether these measures will effectively reduce patients’ medication expenses, given the tendency of pharmacy benefit managers (PBMs) to favor more expensive drugs on their formularies and the implementation challenges faced by PDABs.
The question then arises: How can we promptly assist patients, especially those with multiple chronic conditions, in affording their healthcare? Many of these patients are enrolled in high-deductible plans and struggle to cover all their medical and pharmacy costs.
A significant obstacle to healthcare affordability emerged in 2018 with the introduction of Copay Accumulator Programs by PBMs. These programs prevent patients from applying manufacturer copay cards toward their deductible and maximum out-of-pocket (OOP) costs. The impact of these policies has been devastating, leading to decreased adherence to medications and delayed necessary medical procedures, such as colonoscopies. Copay accumulators do nothing to address the high cost of medical care. They merely shift the burden from insurance companies to patients.
There is a direct solution to help patients, particularly those burdened with high pharmacy bills, afford their medical care. It would be that all payments from patients, including manufacturer copay cards, count toward their deductible and maximum OOP costs. This should apply regardless of whether the insurance plan is fully funded or a self-insured employer plan. This would be an immediate step toward making healthcare more affordable for patients.
Copay Accumulator Programs
How did these detrimental policies, which have been proven to harm patients, originate? It’s interesting that health insurance policies for federal employees do not allow these programs and yet the federal government has done little to protect its citizens from these egregious policies. More on that later.
In 2018, insurance companies and PBMs conceived an idea to introduce what they called copay accumulator adjustment programs. These programs would prevent the use of manufacturer copay cards from counting toward patient deductibles or OOP maximums. They justified this by arguing that manufacturer copay cards encouraged patients to opt for higher-priced brand drugs when lower-cost generics were available.
However, data from IQVIA contradicts this claim. An analysis of copay card usage from 2013 to 2017 revealed that a mere 0.4% of these cards were used for brand-name drugs that had already lost their exclusivity. This indicates that the vast majority of copay cards were not being used to purchase more expensive brand-name drugs when cheaper, generic alternatives were available.
Another argument put forth by one of the large PBMs was that patients with high deductibles don’t have enough “skin in the game” due to their low premiums, and therefore don’t deserve to have their deductible covered by a copay card. This raises the question, “Does a patient with hemophilia or systemic lupus who can’t afford a low deductible plan not have ‘skin in the game’? Is that a fair assessment?” It’s disconcerting to see a multibillion-dollar company dictating who deserves to have their deductible covered. These policies clearly disproportionately harm patients with chronic illnesses, especially those with high deductibles. As a result, many organizations have labeled these policies as discriminatory.
Following the implementation of accumulator programs in 2018 and 2019, many patients were unaware that their copay cards weren’t contributing toward their deductibles. They were taken aback when specialty pharmacies informed them of owing substantial amounts because of unmet deductibles. Consequently, patients discontinued their medications, leading to disease progression and increased costs. The only downside for health insurers and PBMs was the negative publicity associated with patients losing medication access.
Maximizer Programs
By the end of 2019, the three major PBMs had devised a strategy to keep patients on their medication throughout the year, without counting copay cards toward the deductible, and found a way to profit more from these cards, sometimes quadrupling their value. This was the birth of the maximizer programs.
Maximizers exploit a “loophole” in the Affordable Care Act (ACA). The ACA defines Essential Healthcare Benefits (EHB); anything not listed as an EHB is deemed “non-essential.” As a result, neither personal payments nor copay cards count toward deductibles or OOP maximums. Patients were informed that neither their own money nor manufacturer copay cards would count toward their deductible/OOP max.
One of my patients was warned that without enrolling in the maximizer program through SaveOnSP (owned by Express Scripts), she would bear the full cost of the drug, and nothing would count toward her OOP max. Frightened, she enrolled and surrendered her manufacturer copay card to SaveOnSP. Maximizers pocket the maximum value of the copay card, even if it exceeds the insurance plan’s yearly cost share by threefold or more. To do this legally, PBMs increase the patient’s original cost share amount during the plan year to match the value of the manufacturer copay card.
Combating These Programs
Nineteen states, the District of Columbia, and Puerto Rico have outlawed copay accumulators in health plans under state jurisdiction. I personally testified in Louisiana, leading to a ban in our state. CSRO’s award-winning map tool can show if your state has passed the ban on copay accumulator programs. However, many states have not passed bans on copay accumulators and self-insured employer groups, which fall under the Department of Labor and not state regulation, are still unaffected. There is also proposed federal legislation, the “Help Ensure Lower Patient Copays Act,” that would prohibit the use of copay accumulators in exchange plans. Despite having bipartisan support, it is having a hard time getting across the finish line in Congress.
In 2020, the Department of Health and Human Services (HHS) issued a rule prohibiting accumulator programs in all plans if the product was a brand name without a generic alternative. Unfortunately, this rule was rescinded in 2021, allowing copay accumulators even if a lower-cost generic was available.
In a positive turn of events, the US District Court of the District of Columbia overturned the 2021 rule in late 2023, reinstating the 2020 ban on copay accumulators. However, HHS has yet to enforce this ban.
Double Standard
Why is it that our federal government refrains from enforcing bans on copay accumulators for the American public, yet the US Office of Personnel Management (OPM) in its 2024 health plan for federal employees has explicitly stated that it “will decline any arrangements which may manipulate the prescription drug benefit design or incorporate any programs such as copay maximizers, copay optimizers, or other similar programs as these types of benefit designs are not in the best interest of enrollees or the Government.”
If such practices are deemed unsuitable for federal employees, why are they considered acceptable for the rest of the American population? This discrepancy raises important questions about healthcare equity.
In conclusion, the prevalence of medical bankruptcy in our country is a pressing issue that requires immediate attention. The introduction of copay accumulator programs and maximizers by PBMs has led to decreased adherence to needed medications, as well as delay in important medical procedures, exacerbating this situation. An across-the-board ban on these programs would offer immediate relief to many families that no longer can afford needed care.
It is clear that more needs to be done to ensure that all patients, regardless of their financial situation or the nature of their health insurance plan, can afford the healthcare they need. This includes ensuring that patients are not penalized for using manufacturer copay cards to help cover their costs. As we move forward, it is crucial that we continue to advocate for policies that prioritize the health and well-being of all patients.
Dr. Feldman is a rheumatologist in private practice with The Rheumatology Group in New Orleans. She is the CSRO’s vice president of Advocacy and Government Affairs and its immediate past president, as well as past chair of the Alliance for Safe Biologic Medicines and a past member of the American College of Rheumatology insurance subcommittee. You can reach her at [email protected].
The escalating costs of medications and the prevalence of medical bankruptcy in our country have drawn criticism from governments, regulators, and the media. Federal and state governments are exploring various strategies to mitigate this issue, including the Inflation Reduction Act (IRA) for drug price negotiations and the establishment of state Pharmaceutical Drug Affordability Boards (PDABs). However, it’s uncertain whether these measures will effectively reduce patients’ medication expenses, given the tendency of pharmacy benefit managers (PBMs) to favor more expensive drugs on their formularies and the implementation challenges faced by PDABs.
The question then arises: How can we promptly assist patients, especially those with multiple chronic conditions, in affording their healthcare? Many of these patients are enrolled in high-deductible plans and struggle to cover all their medical and pharmacy costs.
A significant obstacle to healthcare affordability emerged in 2018 with the introduction of Copay Accumulator Programs by PBMs. These programs prevent patients from applying manufacturer copay cards toward their deductible and maximum out-of-pocket (OOP) costs. The impact of these policies has been devastating, leading to decreased adherence to medications and delayed necessary medical procedures, such as colonoscopies. Copay accumulators do nothing to address the high cost of medical care. They merely shift the burden from insurance companies to patients.
There is a direct solution to help patients, particularly those burdened with high pharmacy bills, afford their medical care. It would be that all payments from patients, including manufacturer copay cards, count toward their deductible and maximum OOP costs. This should apply regardless of whether the insurance plan is fully funded or a self-insured employer plan. This would be an immediate step toward making healthcare more affordable for patients.
Copay Accumulator Programs
How did these detrimental policies, which have been proven to harm patients, originate? It’s interesting that health insurance policies for federal employees do not allow these programs and yet the federal government has done little to protect its citizens from these egregious policies. More on that later.
In 2018, insurance companies and PBMs conceived an idea to introduce what they called copay accumulator adjustment programs. These programs would prevent the use of manufacturer copay cards from counting toward patient deductibles or OOP maximums. They justified this by arguing that manufacturer copay cards encouraged patients to opt for higher-priced brand drugs when lower-cost generics were available.
However, data from IQVIA contradicts this claim. An analysis of copay card usage from 2013 to 2017 revealed that a mere 0.4% of these cards were used for brand-name drugs that had already lost their exclusivity. This indicates that the vast majority of copay cards were not being used to purchase more expensive brand-name drugs when cheaper, generic alternatives were available.
Another argument put forth by one of the large PBMs was that patients with high deductibles don’t have enough “skin in the game” due to their low premiums, and therefore don’t deserve to have their deductible covered by a copay card. This raises the question, “Does a patient with hemophilia or systemic lupus who can’t afford a low deductible plan not have ‘skin in the game’? Is that a fair assessment?” It’s disconcerting to see a multibillion-dollar company dictating who deserves to have their deductible covered. These policies clearly disproportionately harm patients with chronic illnesses, especially those with high deductibles. As a result, many organizations have labeled these policies as discriminatory.
Following the implementation of accumulator programs in 2018 and 2019, many patients were unaware that their copay cards weren’t contributing toward their deductibles. They were taken aback when specialty pharmacies informed them of owing substantial amounts because of unmet deductibles. Consequently, patients discontinued their medications, leading to disease progression and increased costs. The only downside for health insurers and PBMs was the negative publicity associated with patients losing medication access.
Maximizer Programs
By the end of 2019, the three major PBMs had devised a strategy to keep patients on their medication throughout the year, without counting copay cards toward the deductible, and found a way to profit more from these cards, sometimes quadrupling their value. This was the birth of the maximizer programs.
Maximizers exploit a “loophole” in the Affordable Care Act (ACA). The ACA defines Essential Healthcare Benefits (EHB); anything not listed as an EHB is deemed “non-essential.” As a result, neither personal payments nor copay cards count toward deductibles or OOP maximums. Patients were informed that neither their own money nor manufacturer copay cards would count toward their deductible/OOP max.
One of my patients was warned that without enrolling in the maximizer program through SaveOnSP (owned by Express Scripts), she would bear the full cost of the drug, and nothing would count toward her OOP max. Frightened, she enrolled and surrendered her manufacturer copay card to SaveOnSP. Maximizers pocket the maximum value of the copay card, even if it exceeds the insurance plan’s yearly cost share by threefold or more. To do this legally, PBMs increase the patient’s original cost share amount during the plan year to match the value of the manufacturer copay card.
Combating These Programs
Nineteen states, the District of Columbia, and Puerto Rico have outlawed copay accumulators in health plans under state jurisdiction. I personally testified in Louisiana, leading to a ban in our state. CSRO’s award-winning map tool can show if your state has passed the ban on copay accumulator programs. However, many states have not passed bans on copay accumulators and self-insured employer groups, which fall under the Department of Labor and not state regulation, are still unaffected. There is also proposed federal legislation, the “Help Ensure Lower Patient Copays Act,” that would prohibit the use of copay accumulators in exchange plans. Despite having bipartisan support, it is having a hard time getting across the finish line in Congress.
In 2020, the Department of Health and Human Services (HHS) issued a rule prohibiting accumulator programs in all plans if the product was a brand name without a generic alternative. Unfortunately, this rule was rescinded in 2021, allowing copay accumulators even if a lower-cost generic was available.
In a positive turn of events, the US District Court of the District of Columbia overturned the 2021 rule in late 2023, reinstating the 2020 ban on copay accumulators. However, HHS has yet to enforce this ban.
Double Standard
Why is it that our federal government refrains from enforcing bans on copay accumulators for the American public, yet the US Office of Personnel Management (OPM) in its 2024 health plan for federal employees has explicitly stated that it “will decline any arrangements which may manipulate the prescription drug benefit design or incorporate any programs such as copay maximizers, copay optimizers, or other similar programs as these types of benefit designs are not in the best interest of enrollees or the Government.”
If such practices are deemed unsuitable for federal employees, why are they considered acceptable for the rest of the American population? This discrepancy raises important questions about healthcare equity.
In conclusion, the prevalence of medical bankruptcy in our country is a pressing issue that requires immediate attention. The introduction of copay accumulator programs and maximizers by PBMs has led to decreased adherence to needed medications, as well as delay in important medical procedures, exacerbating this situation. An across-the-board ban on these programs would offer immediate relief to many families that no longer can afford needed care.
It is clear that more needs to be done to ensure that all patients, regardless of their financial situation or the nature of their health insurance plan, can afford the healthcare they need. This includes ensuring that patients are not penalized for using manufacturer copay cards to help cover their costs. As we move forward, it is crucial that we continue to advocate for policies that prioritize the health and well-being of all patients.
Dr. Feldman is a rheumatologist in private practice with The Rheumatology Group in New Orleans. She is the CSRO’s vice president of Advocacy and Government Affairs and its immediate past president, as well as past chair of the Alliance for Safe Biologic Medicines and a past member of the American College of Rheumatology insurance subcommittee. You can reach her at [email protected].
The escalating costs of medications and the prevalence of medical bankruptcy in our country have drawn criticism from governments, regulators, and the media. Federal and state governments are exploring various strategies to mitigate this issue, including the Inflation Reduction Act (IRA) for drug price negotiations and the establishment of state Pharmaceutical Drug Affordability Boards (PDABs). However, it’s uncertain whether these measures will effectively reduce patients’ medication expenses, given the tendency of pharmacy benefit managers (PBMs) to favor more expensive drugs on their formularies and the implementation challenges faced by PDABs.
The question then arises: How can we promptly assist patients, especially those with multiple chronic conditions, in affording their healthcare? Many of these patients are enrolled in high-deductible plans and struggle to cover all their medical and pharmacy costs.
A significant obstacle to healthcare affordability emerged in 2018 with the introduction of Copay Accumulator Programs by PBMs. These programs prevent patients from applying manufacturer copay cards toward their deductible and maximum out-of-pocket (OOP) costs. The impact of these policies has been devastating, leading to decreased adherence to medications and delayed necessary medical procedures, such as colonoscopies. Copay accumulators do nothing to address the high cost of medical care. They merely shift the burden from insurance companies to patients.
There is a direct solution to help patients, particularly those burdened with high pharmacy bills, afford their medical care. It would be that all payments from patients, including manufacturer copay cards, count toward their deductible and maximum OOP costs. This should apply regardless of whether the insurance plan is fully funded or a self-insured employer plan. This would be an immediate step toward making healthcare more affordable for patients.
Copay Accumulator Programs
How did these detrimental policies, which have been proven to harm patients, originate? It’s interesting that health insurance policies for federal employees do not allow these programs and yet the federal government has done little to protect its citizens from these egregious policies. More on that later.
In 2018, insurance companies and PBMs conceived an idea to introduce what they called copay accumulator adjustment programs. These programs would prevent the use of manufacturer copay cards from counting toward patient deductibles or OOP maximums. They justified this by arguing that manufacturer copay cards encouraged patients to opt for higher-priced brand drugs when lower-cost generics were available.
However, data from IQVIA contradicts this claim. An analysis of copay card usage from 2013 to 2017 revealed that a mere 0.4% of these cards were used for brand-name drugs that had already lost their exclusivity. This indicates that the vast majority of copay cards were not being used to purchase more expensive brand-name drugs when cheaper, generic alternatives were available.
Another argument put forth by one of the large PBMs was that patients with high deductibles don’t have enough “skin in the game” due to their low premiums, and therefore don’t deserve to have their deductible covered by a copay card. This raises the question, “Does a patient with hemophilia or systemic lupus who can’t afford a low deductible plan not have ‘skin in the game’? Is that a fair assessment?” It’s disconcerting to see a multibillion-dollar company dictating who deserves to have their deductible covered. These policies clearly disproportionately harm patients with chronic illnesses, especially those with high deductibles. As a result, many organizations have labeled these policies as discriminatory.
Following the implementation of accumulator programs in 2018 and 2019, many patients were unaware that their copay cards weren’t contributing toward their deductibles. They were taken aback when specialty pharmacies informed them of owing substantial amounts because of unmet deductibles. Consequently, patients discontinued their medications, leading to disease progression and increased costs. The only downside for health insurers and PBMs was the negative publicity associated with patients losing medication access.
Maximizer Programs
By the end of 2019, the three major PBMs had devised a strategy to keep patients on their medication throughout the year, without counting copay cards toward the deductible, and found a way to profit more from these cards, sometimes quadrupling their value. This was the birth of the maximizer programs.
Maximizers exploit a “loophole” in the Affordable Care Act (ACA). The ACA defines Essential Healthcare Benefits (EHB); anything not listed as an EHB is deemed “non-essential.” As a result, neither personal payments nor copay cards count toward deductibles or OOP maximums. Patients were informed that neither their own money nor manufacturer copay cards would count toward their deductible/OOP max.
One of my patients was warned that without enrolling in the maximizer program through SaveOnSP (owned by Express Scripts), she would bear the full cost of the drug, and nothing would count toward her OOP max. Frightened, she enrolled and surrendered her manufacturer copay card to SaveOnSP. Maximizers pocket the maximum value of the copay card, even if it exceeds the insurance plan’s yearly cost share by threefold or more. To do this legally, PBMs increase the patient’s original cost share amount during the plan year to match the value of the manufacturer copay card.
Combating These Programs
Nineteen states, the District of Columbia, and Puerto Rico have outlawed copay accumulators in health plans under state jurisdiction. I personally testified in Louisiana, leading to a ban in our state. CSRO’s award-winning map tool can show if your state has passed the ban on copay accumulator programs. However, many states have not passed bans on copay accumulators and self-insured employer groups, which fall under the Department of Labor and not state regulation, are still unaffected. There is also proposed federal legislation, the “Help Ensure Lower Patient Copays Act,” that would prohibit the use of copay accumulators in exchange plans. Despite having bipartisan support, it is having a hard time getting across the finish line in Congress.
In 2020, the Department of Health and Human Services (HHS) issued a rule prohibiting accumulator programs in all plans if the product was a brand name without a generic alternative. Unfortunately, this rule was rescinded in 2021, allowing copay accumulators even if a lower-cost generic was available.
In a positive turn of events, the US District Court of the District of Columbia overturned the 2021 rule in late 2023, reinstating the 2020 ban on copay accumulators. However, HHS has yet to enforce this ban.
Double Standard
Why is it that our federal government refrains from enforcing bans on copay accumulators for the American public, yet the US Office of Personnel Management (OPM) in its 2024 health plan for federal employees has explicitly stated that it “will decline any arrangements which may manipulate the prescription drug benefit design or incorporate any programs such as copay maximizers, copay optimizers, or other similar programs as these types of benefit designs are not in the best interest of enrollees or the Government.”
If such practices are deemed unsuitable for federal employees, why are they considered acceptable for the rest of the American population? This discrepancy raises important questions about healthcare equity.
In conclusion, the prevalence of medical bankruptcy in our country is a pressing issue that requires immediate attention. The introduction of copay accumulator programs and maximizers by PBMs has led to decreased adherence to needed medications, as well as delay in important medical procedures, exacerbating this situation. An across-the-board ban on these programs would offer immediate relief to many families that no longer can afford needed care.
It is clear that more needs to be done to ensure that all patients, regardless of their financial situation or the nature of their health insurance plan, can afford the healthcare they need. This includes ensuring that patients are not penalized for using manufacturer copay cards to help cover their costs. As we move forward, it is crucial that we continue to advocate for policies that prioritize the health and well-being of all patients.
Dr. Feldman is a rheumatologist in private practice with The Rheumatology Group in New Orleans. She is the CSRO’s vice president of Advocacy and Government Affairs and its immediate past president, as well as past chair of the Alliance for Safe Biologic Medicines and a past member of the American College of Rheumatology insurance subcommittee. You can reach her at [email protected].
Paclitaxel Drug-Drug Interactions in the Military Health System
Background
Paclitaxel was first derived from the bark of the yew tree (Taxus brevifolia). It was discovered as part of a National Cancer Institute program screen of plants and natural products with putative anticancer activity during the 1960s.1-9 Paclitaxel works by suppressing spindle microtube dynamics, which results in the blockage of the metaphase-anaphase transitions, inhibition of mitosis, and induction of apoptosis in a broad spectrum of cancer cells. Paclitaxel also displayed additional anticancer activities, including the suppression of cell proliferation and antiangiogenic effects. However, since the growth of normal body cells may also be affected, other adverse effects (AEs) will also occur.8-18
Two different chemotherapy drugs contain paclitaxel—paclitaxel and nab-paclitaxel—and the US Food and Drug Administration (FDA) recognizes them as separate entities.19-21 Taxol (paclitaxel) was approved by the FDA in 1992 for treating advanced ovarian cancer.20 It has since been approved for the treatment of metastatic breast cancer, AIDS-related Kaposi sarcoma (as an orphan drug), non-small cell lung cancer (NSCLC), and cervical cancers (in combination withbevacizumab) in 1994, 1997, 1999, and 2014, respectively.21 Since 2002, a generic version of Taxol, known as paclitaxel injectable, has been FDA-approved from different manufacturers. According to the National Cancer Institute, a combination of carboplatin and Taxol is approved to treat carcinoma of unknown primary, cervical, endometrial, NSCLC, ovarian, and thymoma cancers.19 Abraxane (nab-paclitaxel) was FDA-approved to treat metastatic breast cancer in 2005. It was later approved for first-line treatment of advanced NSCLC and late-stage pancreatic cancer in 2012 and 2013, respectively. In 2018 and 2020, both Taxol and Abraxane were approved for first-line treatment of metastatic squamous cell NSCLC in combination with carboplatin and pembrolizumab and metastatic triple-negative breast cancer in combination with pembrolizumab, respectively.22-26 In 2019, Abraxane was approved with atezolizumab to treat metastatic triple-negative breast cancer, but this approval was withdrawn in 2021. In 2022, a generic version of Abraxane, known as paclitaxel protein-bound, was released in the United States. Furthermore, paclitaxel-containing formulations also are being studied in the treatment of other types of cancer.19-32
One of the main limitations of paclitaxel is its low solubility in water, which complicates its drug supply. To distribute this hydrophobic anticancer drug efficiently, paclitaxel is formulated and administered to patients via polyethoxylated castor oil or albumin-bound (nab-paclitaxel). However, polyethoxylated castor oil induces complement activation and is the cause of common hypersensitivity reactions related to paclitaxel use.2,17,33-38 Therefore, many alternatives to polyethoxylated castor oil have been researched.
Since 2000, new paclitaxel formulations have emerged using nanomedicine techniques. The difference between these formulations is the drug vehicle. Different paclitaxel-based nanotechnological vehicles have been developed and approved, such as albumin-based nanoparticles, polymeric lipidic nanoparticles, polymeric micelles, and liposomes, with many others in clinical trial phases.3,37 Albumin-based nanoparticles have a high response rate (33%), whereas the response rate for polyethoxylated castor oil is 25% in patients with metastatic breast cancer.33,39-52 The use of paclitaxel dimer nanoparticles also has been proposed as a method for increasing drug solubility.33,53
Paclitaxel is metabolized by cytochrome P450 (CYP) isoenzymes 2C8 and 3A4. When administering paclitaxel with known inhibitors, inducers, or substrates of CYP2C8 or CYP3A4, caution is required.19-22 Regulations for CYP research were not issued until 2008, so potential interactions between paclitaxel and other drugs have not been extensively evaluated in clinical trials. A study of 12 kinase inhibitors showed strong inhibition of CYP2C8 and/or CYP3A4 pathways by these inhibitors, which could alter the ratio of paclitaxel metabolites in vivo, leading to clinically relevant changes.54 Differential metabolism has been linked to paclitaxel-induced neurotoxicity in patients with cancer.55 Nonetheless, variants in the CYP2C8, CYP3A4, CYP3A5, and ABCB1 genes do not account for significant interindividual variability in paclitaxel pharmacokinetics.56 In liver microsomes, losartan inhibited paclitaxel metabolism when used at concentrations > 50 µmol/L.57 Many drug-drug interaction (DDI) studies of CYP2C8 and CYP3A4 have shown similar results for paclitaxel.58-64
The goals of this study are to investigate prescribed drugs used with paclitaxel and determine patient outcomes through several Military Health System (MHS) databases. The investigation focused on (1) the functions of paclitaxel; (2) identifying AEs that patients experienced; (3) evaluating differences when paclitaxel is used alone vs concomitantly and between the completed vs discontinued treatment groups; (4) identifying all drugs used during paclitaxel treatment; and (5) evaluating DDIs with antidepressants (that have an FDA boxed warning and are known to have DDIs confirmed in previous publications) and other drugs.65-67
The Walter Reed National Military Medical Center in Bethesda, Maryland, institutionalreview board approved the study protocol and ensured compliance with the Health Insurance Portability and Accountability Act as an exempt protocol. The Joint Pathology Center (JPC) of the US Department of Defense (DoD) Cancer Registry Program and MHS data experts from the Comprehensive Ambulatory/Professional Encounter Record (CAPER) and the Pharmacy Data Transaction Service (PDTS) provided data for the analysis.
METHODS
The DoD Cancer Registry Program was established in 1986 and currently contains data from 1998 to 2024. CAPER and PDTS are part of the MHS Data Repository/Management Analysis and Reporting Tool database. Each observation in the CAPER record represents an ambulatory encounter at a military treatment facility (MTF). CAPER includes data from 2003 to 2024.
Each observation in the PDTS record represents a prescription filled for an MHS beneficiary at an MTF through the TRICARE mail-order program or a US retail pharmacy. Missing from this record are prescriptions filled at international civilian pharmacies and inpatient pharmacy prescriptions. The MHS Data Repository PDTS record is available from 2002 to 2024. The legacy Composite Health Care System is being replaced by GENESIS at MTFs.
Data Extraction Design
The study design involved a cross-sectional analysis. We requested data extraction for paclitaxel from 1998 to 2022. Data from the DoD Cancer Registry Program were used to identify patients who received cancer treatment. Once patients were identified, the CAPER database was searched for diagnoses to identify other health conditions, whereas the PDTS database was used to populate a list of prescription medications filled during chemotherapy treatment.
Data collected from the JPC included cancer treatment, cancer information, demographics, and physicians’ comments on AEs. Collected data from the MHS include diagnosis and filled prescription history from initiation to completion of the therapy period (or 2 years after the diagnosis date). For the analysis of the DoD Cancer Registry Program and CAPER databases, we used all collected data without excluding any. When analyzing PDTS data, we excluded patients with PDTS data but without a record of paclitaxel being filled, or medications filled outside the chemotherapy period (by evaluating the dispensed date and day of supply).
Data Extraction Analysis
The Surveillance, Epidemiology, and End Results Program Coding and Staging Manual 2016 and the International Classification of Diseases for Oncology, 3rd edition, 1st revision, were used to decode disease and cancer types.68,69 Data sorting and analysis were performed using Microsoft Excel. The percentage for the total was calculated by using the number of patients or data available within the paclitaxel groups divided by the total number of patients or data variables. The subgroup percentage was calculated by using the number of patients or data available within the subgroup divided by the total number of patients in that subgroup.
In alone vs concomitant and completed vs discontinued treatment groups, a 2-tailed, 2-sample z test was used to statistical significance (P < .05) using a statistics website.70 Concomitant was defined as paclitaxel taken with other antineoplastic agent(s) before, after, or at the same time as cancer therapy. For the retrospective data analysis, physicians’ notes with a period, comma, forward slash, semicolon, or space between medication names were interpreted as concurrent, whereas plus (+), minus/plus (-/+), or “and” between drug names that were dispensed on the same day were interpreted as combined with known common combinations: 2 drugs (DM886 paclitaxel and carboplatin and DM881-TC-1 paclitaxel and cisplatin) or 3 drugs (DM887-ACT doxorubicin, cyclophosphamide, and paclitaxel). Completed treatment was defined as paclitaxel as the last medication the patient took without recorded AEs; switching or experiencing AEs was defined as discontinued treatment.
RESULTS
The JPC provided 702 entries for 687 patients with a mean age of 56 years (range, 2 months to 88 years) who were treated with paclitaxel from March 1996 to October 2021. Fifteen patients had duplicate entries because they had multiple cancer sites or occurrences. There were 623 patients (89%) who received paclitaxel for FDA-approved indications. The most common types of cancer identified were 344 patients with breast cancer (49%), 91 patients with lung cancer (13%), 79 patients with ovarian cancer (11%), and 75 patients with endometrial cancer (11%) (Table 1). Seventy-nine patients (11%) received paclitaxel for cancers that were not for FDA-approved indications, including 19 for cancers of the fallopian tube (3%) and 17 for esophageal cancer (2%) (Table 2).
There were 477 patients (68%) aged > 50 years. A total of 304 patients (43%) had a stage III or IV cancer diagnosis and 398 (57%) had stage II or lower (combination of data for stages 0, I, and II; not applicable; and unknown) cancer diagnosis. For systemic treatment, 16 patients (2%) were treated with paclitaxel alone and 686 patients (98%) received paclitaxel concomitantly with additional chemotherapy: 59 patients (9%) in the before or after group, 410 patients (58%) had a 2-drug combination, 212 patients (30%) had a 3-drug combination, and 5 patients (1%) had a 4-drug combination. In addition, for doublet therapies, paclitaxel combined with carboplatin, trastuzumab, gemcitabine, or cisplatin had more patients (318, 58, 12, and 11, respectively) than other combinations (≤ 4 patients). For triplet therapies, paclitaxel combined withdoxorubicin plus cyclophosphamide or carboplatin plus bevacizumab had more patients (174 and 20, respectively) than other combinations, including quadruplet therapies (≤ 4 patients) (Table 3).
Patients were more likely to discontinue paclitaxel if they received concomitant treatment. None of the 16 patients receiving paclitaxel monotherapy experienced AEs, whereas 364 of 686 patients (53%) treated concomitantly discontinued (P < .001). Comparisons of 1 drug vs combination (2 to 4 drugs) and use for treating cancers that were FDA-approved indications vs off-label use were significant (P < .001), whereas comparisons of stage II or lower vs stage III and IV cancer and of those aged ≤ 50 years vs aged > 50 years were not significant (P = .50 andP = .30, respectively) (Table 4).
Among the 364 patients who had concomitant treatment and had discontinued their treatment, 332 (91%) switched treatments with no AEs documented and 32 (9%) experienced fatigue with pneumonia, mucositis, neuropathy, neurotoxicity, neutropenia, pneumonitis, allergic or hypersensitivity reaction, or an unknown AE. Patients who discontinued treatment because of unknown AEs had a physician’s note that detailed progressive disease, a significant decline in performance status, and another unknown adverse effect due to a previous sinus tract infection and infectious colitis (Table 5).
Management Analysis and Reporting Tool Database
MHS data analysts provided data on diagnoses for 639 patients among 687 submitteddiagnoses, with 294 patients completing and 345 discontinuing paclitaxel treatment. Patients in the completed treatment group had 3 to 258 unique health conditions documented, while patients in the discontinued treatment group had 4 to 181 unique health conditions documented. The MHS reported 3808 unique diagnosis conditions for the completed group and 3714 for the discontinued group (P = .02).
The mean (SD) number of diagnoses was 51 (31) for the completed and 55 (28) for the discontinued treatment groups (Figure). Among 639 patients who received paclitaxel, the top 5 diagnoses were administrative, including encounters for other administrative examinations; antineoplastic chemotherapy; administrative examination for unspecified; other specified counseling; and adjustment and management of vascular access device. The database does not differentiate between administrative and clinically significant diagnoses.
MHS data analysts provided data for 336 of 687 submitted patients who were prescribed paclitaxel; 46 patients had no PDTS data, and 305 patients had PDTS data without paclitaxel, Taxol, or Abraxane dispensed. Medications that were filled outside the chemotherapy period were removed by evaluating the dispensed date and day of supply. Among these 336 patients, 151 completed the treatment and 185 discontinued, with 14 patients experiencing documented AEs. Patients in the completed treatment group filled 9 to 56 prescriptions while patients in the discontinued treatment group filled 6 to 70 prescriptions.Patients in the discontinued group filled more prescriptions than those who completed treatment: 793 vs 591, respectively (P = .34).
The mean (SD) number of filled prescription drugs was 24 (9) for the completed and 34 (12) for the discontinued treatment group. The 5 most filled prescriptions with paclitaxel from 336 patients with PDTS data were dexamethasone (324 prescriptions with 14 recorded AEs), diphenhydramine (296 prescriptions with 12 recorded AEs), ondansetron (277 prescriptions with 11 recorded AEs), prochlorperazine (265 prescriptions with 12 recorded AEs), and sodium chloride (232 prescriptions with 11 recorded AEs).
DISCUSSION
As a retrospective review, this study is more limited in the strength of its conclusions when compared to randomized control trials. The DoD Cancer Registry Program only contains information about cancer types, stages, treatment regimens, and physicians’ notes. Therefore, noncancer drugs are based solely on the PDTS database. In most cases, physicians' notes on AEs were not detailed. There was no distinction between initial vs later lines of therapy and dosage reductions. The change in status or appearance of a new medical condition did not indicate whether paclitaxel caused the changes to develop or directly worsen a pre-existing condition. The PDTS records prescriptions filled, but that may not reflect patients taking prescriptions.
Paclitaxel
Paclitaxel has a long list of both approved and off-label uses in malignancies as a primary agent and in conjunction with other drugs. The FDA prescribing information for Taxol and Abraxane was last updated in April 2011 and September 2020, respectively.20,21 The National Institutes of Health National Library of Medicine has the current update for paclitaxel on July 2023.19,22 Thus, the prescribed information for paclitaxel referenced in the database may not always be up to date. The combinations of paclitaxel with bevacizumab, carboplatin, or carboplatin and pembrolizumab were not in the Taxol prescribing information. Likewise, a combination of nab-paclitaxel with atezolizumab or carboplatin and pembrolizumab is missing in the Abraxane prescribing information.22-27
The generic name is not the same as a generic drug, which may have slight differences from the brand name product.71 The generic drug versions of Taxol and Abraxane have been approved by the FDA as paclitaxel injectable and paclitaxel-protein bound, respectively. There was a global shortage of nab-paclitaxel from October 2021 to June 2022 because of a manufacturing problem.72 During this shortage, data showed similar comments from physician documents that treatment switched to Taxol due to the Abraxane shortage.
Of 336 patients in the PDTS database with dispensed paclitaxel prescriptions, 276 received paclitaxel (year dispensed, 2013-2022), 27 received Abraxane (year dispensed, 2013-2022), 47 received Taxol (year dispensed, 2004-2015), 8 received both Abraxane and paclitaxel, and 6 received both Taxol and paclitaxel. Based on this information, it appears that the distinction between the drugs was not made in the PDTS until after 2015, 10 years after Abraxane received FDA approval. Abraxane was prescribed in the MHS in 2013, 8 years after FDA approval. There were a few comparison studies of Abraxane and Taxol.73-76
Safety and effectiveness in pediatric patients have not been established for paclitaxel. According to the DoD Cancer Registry Program, the youngest patient was aged 2 months. In 2021, this patient was diagnosed with corpus uteri and treated with carboplatin and Taxol in course 1; in course 2, the patient reacted to Taxol; in course 3, Taxol was replaced with Abraxane; in courses 4 to 7, the patient was treated with carboplatin only.
Discontinued Treatment
Ten patients had prescribed Taxol that was changed due to AEs: 1 was switched to Abraxane and atezolizumab, 3 switched to Abraxane, 2 switched to docetaxel, 1 switched to doxorubicin, and 3 switched to pembrolizumab (based on physician’s comments). Of the 10 patients, 7 had Taxol reaction, 2 experienced disease progression, and 1 experienced high programmed death–ligand 1 expression (this patient with breast cancer was switched to Abraxane and atezolizumab during the accelerated FDA approval phase for atezolizumab, which was later revoked). Five patients were treated with carboplatin and Taxol for cancer of the anal canal (changed to pembrolizumab after disease progression), lung not otherwise specified (changed to carboplatin and pembrolizumab due to Taxol reaction), lower inner quadrant of the breast (changed to doxorubicin due to hypersensitivity reaction), corpus uteri (changed to Abraxane due to Taxol reaction), and ovary (changed to docetaxel due to Taxol reaction). Three patients were treated with doxorubicin, cyclophosphamide, and Taxol for breast cancer; 2 patients with breast cancer not otherwise specified switched to Abraxane due to cardiopulmonary hypersensitivity and Taxol reaction and 1 patient with cancer of the upper outer quadrant of the breast changed to docetaxel due to allergic reaction. One patient, who was treated with paclitaxel, ifosfamide, and cisplatin for metastasis of the lower lobe of the lung and kidney cancer, experienced complications due to infectious colitis (treated with ciprofloxacin) and then switched to pembrolizumab after the disease progressed. These AEs are known in paclitaxel medical literature on paclitaxel AEs.19-24,77-81
Combining 2 or more treatments to target cancer-inducing or cell-sustaining pathways is a cornerstone of chemotherapy.82-84 Most combinations are given on the same day, but some are not. For 3- or 4-drug combinations, doxorubicin and cyclophosphamide were given first, followed by paclitaxel with or withouttrastuzumab, carboplatin, or pembrolizumab. Only 16 patients (2%) were treated with paclitaxel alone; therefore, the completed and discontinued treatment groups are mostly concomitant treatment. As a result, the comparisons of the completed and discontinued treatment groups were almost the same for the diagnosis. The PDTS data have a better result because 2 exclusion criteria were applied before narrowing the analysis down to paclitaxel treatment specifically.
Antidepressants and Other Drugs
Drug response can vary from person to person and can lead to treatment failure related to AEs. One major factor in drug metabolism is CYP.85 CYP2C8 is the major pathway for paclitaxel and CYP3A4 is the minor pathway. When evaluating the noncancer drugs, there were no reports of CYP2C8 inhibition or induction.Over the years, many DDI warnings have been issued for paclitaxel with different drugs in various electronic resources.
Oncologists follow guidelines to prevent DDIs, as paclitaxel is known to have severe, moderate, and minor interactions with other drugs. Among 687 patients, 261 (38%) were prescribed any of 14 antidepressants. Eight of these antidepressants (amitriptyline, citalopram, desipramine, doxepin, venlafaxine, escitalopram, nortriptyline, and trazodone) are metabolized, 3 (mirtazapine, sertraline, and fluoxetine) are metabolized and inhibited, 2 (bupropion and duloxetine) are neither metabolized nor inhibited, and 1 (paroxetine) is inhibited by CYP3A4. Duloxetine, venlafaxine, and trazodone were more commonly dispensed (84, 78, and 42 patients, respectively) than others (≤ 33 patients).
Of 32 patients with documented AEs,14 (44%) had 168 dispensed drugs in the PDTS database. Six patients (19%) were treated with doxorubicin and cyclophosphamide followed by paclitaxel for breast cancer; 6 (19%) were treated with carboplatin and paclitaxel for cancer of the lung (n = 3), corpus uteri (n = 2), and ovary (n = 1); 1 patient (3%) was treated with carboplatin and paclitaxel, then switched to carboplatin, bevacizumab, and paclitaxel, and then completed treatment with carboplatin and paclitaxel for an unspecified female genital cancer; and 1 patient (3%) was treated with cisplatin, ifosfamide, and paclitaxel for metastasis of the lower lobe lung and kidney cancer.
The 14 patients with PDTS data had 18 cancer drugs dispensed. Eleven had moderate interaction reports and 7 had no interaction reports. A total of 165 noncancer drugs were dispensed, of which 3 were antidepressants and had no interactions reported, 8 had moderate interactions reported, and 2 had minor interactions with Taxol and Abraxane, respectively (Table 6).86-129
Of 3 patients who were dispensed bupropion, nortriptyline, or paroxetine, 1 patient with breast cancer was treated with doxorubicin andcyclophosphamide, followed by paclitaxel with bupropion, nortriptyline, pegfilgrastim,dexamethasone, and 17 other noncancer drugs that had no interaction report dispensed during paclitaxel treatment. Of 2 patients with lung cancer, 1 patient was treated with carboplatin and paclitaxel with nortriptyline, dexamethasone, and 13 additional medications, and the second patient was treated with paroxetine, cimetidine, dexamethasone, and 12 other medications. Patients were dispensed up to6 noncancer medications on the same day as paclitaxel administration to control the AEs, not including the prodrugs filled before the treatments. Paroxetine and cimetidine have weak inhibition, and dexamethasone has weak induction of CYP3A4. Therefore, while 1:1 DDIs might have little or no effect with weak inhibit/induce CYP3A4 drugs, 1:1:1 or more combinations could have a different outcome (confirmed in previous publications).65-67
Dispensed on the same day may not mean taken at the same time. One patient experienced an AE with dispensed 50 mg losartan, carboplatin plus paclitaxel, dexamethasone, and 6 other noncancer drugs. Losartan inhibits paclitaxel, which can lead to negative AEs.57,66,67 However, there were no blood or plasma samples taken to confirm the losartan was taken at the same time as the paclitaxel given this was not a clinical trial.
Conclusions
This retrospective study discusses the use of paclitaxel in the MHS and the potential DDIs associated with it. The study population consisted mostly of active-duty personnel, who are required to be healthy or have controlled or nonactive medical diagnoses and be physically fit. This group is mixed with dependents and retirees that are more reflective of the average US population. As a result, this patient population is healthier than the general population, with a lower prevalence of common illnesses such as diabetes and obesity. The study aimed to identify drugs used alongside paclitaxel treatment. While further research is needed to identify potential DDIs among patients who experienced AEs, in vitro testing will need to be conducted before confirming causality. The low number of AEs experienced by only 32 of 702 patients (5%), with no deaths during paclitaxel treatment, indicates that the drug is generally well tolerated. Although this study cannot conclude that concomitant use with noncancer drugs led to the discontinuation of paclitaxel, we can conclude that there seems to be no significant DDIsidentified between paclitaxel and antidepressants. This comprehensive overview provides clinicians with a complete picture of paclitaxel use for 27 years (1996-2022), enabling them to make informed decisions about paclitaxel treatment.
Acknowledgments
The Department of Research Program funds at Walter Reed National Military Medical Center supported this protocol. We sincerely appreciate the contribution of data extraction from the Joint Pathology Center teams (Francisco J. Rentas, John D. McGeeney, Beatriz A. Hallo, and Johnny P. Beason) and the MHS database personnel (Maj Ryan Costantino, Brandon E. Jenkins, and Alexander G. Rittel). We gratefully thank you for the protocol support from the Department of Research programs: CDR Martin L. Boese, CDR Wesley R. Campbell, Maj. Abhimanyu Chandel, CDR Ling Ye, Chelsea N. Powers, Yaling Zhou, Elizabeth Schafer, Micah Stretch, Diane Beaner, and Adrienne Woodard.
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Background
Paclitaxel was first derived from the bark of the yew tree (Taxus brevifolia). It was discovered as part of a National Cancer Institute program screen of plants and natural products with putative anticancer activity during the 1960s.1-9 Paclitaxel works by suppressing spindle microtube dynamics, which results in the blockage of the metaphase-anaphase transitions, inhibition of mitosis, and induction of apoptosis in a broad spectrum of cancer cells. Paclitaxel also displayed additional anticancer activities, including the suppression of cell proliferation and antiangiogenic effects. However, since the growth of normal body cells may also be affected, other adverse effects (AEs) will also occur.8-18
Two different chemotherapy drugs contain paclitaxel—paclitaxel and nab-paclitaxel—and the US Food and Drug Administration (FDA) recognizes them as separate entities.19-21 Taxol (paclitaxel) was approved by the FDA in 1992 for treating advanced ovarian cancer.20 It has since been approved for the treatment of metastatic breast cancer, AIDS-related Kaposi sarcoma (as an orphan drug), non-small cell lung cancer (NSCLC), and cervical cancers (in combination withbevacizumab) in 1994, 1997, 1999, and 2014, respectively.21 Since 2002, a generic version of Taxol, known as paclitaxel injectable, has been FDA-approved from different manufacturers. According to the National Cancer Institute, a combination of carboplatin and Taxol is approved to treat carcinoma of unknown primary, cervical, endometrial, NSCLC, ovarian, and thymoma cancers.19 Abraxane (nab-paclitaxel) was FDA-approved to treat metastatic breast cancer in 2005. It was later approved for first-line treatment of advanced NSCLC and late-stage pancreatic cancer in 2012 and 2013, respectively. In 2018 and 2020, both Taxol and Abraxane were approved for first-line treatment of metastatic squamous cell NSCLC in combination with carboplatin and pembrolizumab and metastatic triple-negative breast cancer in combination with pembrolizumab, respectively.22-26 In 2019, Abraxane was approved with atezolizumab to treat metastatic triple-negative breast cancer, but this approval was withdrawn in 2021. In 2022, a generic version of Abraxane, known as paclitaxel protein-bound, was released in the United States. Furthermore, paclitaxel-containing formulations also are being studied in the treatment of other types of cancer.19-32
One of the main limitations of paclitaxel is its low solubility in water, which complicates its drug supply. To distribute this hydrophobic anticancer drug efficiently, paclitaxel is formulated and administered to patients via polyethoxylated castor oil or albumin-bound (nab-paclitaxel). However, polyethoxylated castor oil induces complement activation and is the cause of common hypersensitivity reactions related to paclitaxel use.2,17,33-38 Therefore, many alternatives to polyethoxylated castor oil have been researched.
Since 2000, new paclitaxel formulations have emerged using nanomedicine techniques. The difference between these formulations is the drug vehicle. Different paclitaxel-based nanotechnological vehicles have been developed and approved, such as albumin-based nanoparticles, polymeric lipidic nanoparticles, polymeric micelles, and liposomes, with many others in clinical trial phases.3,37 Albumin-based nanoparticles have a high response rate (33%), whereas the response rate for polyethoxylated castor oil is 25% in patients with metastatic breast cancer.33,39-52 The use of paclitaxel dimer nanoparticles also has been proposed as a method for increasing drug solubility.33,53
Paclitaxel is metabolized by cytochrome P450 (CYP) isoenzymes 2C8 and 3A4. When administering paclitaxel with known inhibitors, inducers, or substrates of CYP2C8 or CYP3A4, caution is required.19-22 Regulations for CYP research were not issued until 2008, so potential interactions between paclitaxel and other drugs have not been extensively evaluated in clinical trials. A study of 12 kinase inhibitors showed strong inhibition of CYP2C8 and/or CYP3A4 pathways by these inhibitors, which could alter the ratio of paclitaxel metabolites in vivo, leading to clinically relevant changes.54 Differential metabolism has been linked to paclitaxel-induced neurotoxicity in patients with cancer.55 Nonetheless, variants in the CYP2C8, CYP3A4, CYP3A5, and ABCB1 genes do not account for significant interindividual variability in paclitaxel pharmacokinetics.56 In liver microsomes, losartan inhibited paclitaxel metabolism when used at concentrations > 50 µmol/L.57 Many drug-drug interaction (DDI) studies of CYP2C8 and CYP3A4 have shown similar results for paclitaxel.58-64
The goals of this study are to investigate prescribed drugs used with paclitaxel and determine patient outcomes through several Military Health System (MHS) databases. The investigation focused on (1) the functions of paclitaxel; (2) identifying AEs that patients experienced; (3) evaluating differences when paclitaxel is used alone vs concomitantly and between the completed vs discontinued treatment groups; (4) identifying all drugs used during paclitaxel treatment; and (5) evaluating DDIs with antidepressants (that have an FDA boxed warning and are known to have DDIs confirmed in previous publications) and other drugs.65-67
The Walter Reed National Military Medical Center in Bethesda, Maryland, institutionalreview board approved the study protocol and ensured compliance with the Health Insurance Portability and Accountability Act as an exempt protocol. The Joint Pathology Center (JPC) of the US Department of Defense (DoD) Cancer Registry Program and MHS data experts from the Comprehensive Ambulatory/Professional Encounter Record (CAPER) and the Pharmacy Data Transaction Service (PDTS) provided data for the analysis.
METHODS
The DoD Cancer Registry Program was established in 1986 and currently contains data from 1998 to 2024. CAPER and PDTS are part of the MHS Data Repository/Management Analysis and Reporting Tool database. Each observation in the CAPER record represents an ambulatory encounter at a military treatment facility (MTF). CAPER includes data from 2003 to 2024.
Each observation in the PDTS record represents a prescription filled for an MHS beneficiary at an MTF through the TRICARE mail-order program or a US retail pharmacy. Missing from this record are prescriptions filled at international civilian pharmacies and inpatient pharmacy prescriptions. The MHS Data Repository PDTS record is available from 2002 to 2024. The legacy Composite Health Care System is being replaced by GENESIS at MTFs.
Data Extraction Design
The study design involved a cross-sectional analysis. We requested data extraction for paclitaxel from 1998 to 2022. Data from the DoD Cancer Registry Program were used to identify patients who received cancer treatment. Once patients were identified, the CAPER database was searched for diagnoses to identify other health conditions, whereas the PDTS database was used to populate a list of prescription medications filled during chemotherapy treatment.
Data collected from the JPC included cancer treatment, cancer information, demographics, and physicians’ comments on AEs. Collected data from the MHS include diagnosis and filled prescription history from initiation to completion of the therapy period (or 2 years after the diagnosis date). For the analysis of the DoD Cancer Registry Program and CAPER databases, we used all collected data without excluding any. When analyzing PDTS data, we excluded patients with PDTS data but without a record of paclitaxel being filled, or medications filled outside the chemotherapy period (by evaluating the dispensed date and day of supply).
Data Extraction Analysis
The Surveillance, Epidemiology, and End Results Program Coding and Staging Manual 2016 and the International Classification of Diseases for Oncology, 3rd edition, 1st revision, were used to decode disease and cancer types.68,69 Data sorting and analysis were performed using Microsoft Excel. The percentage for the total was calculated by using the number of patients or data available within the paclitaxel groups divided by the total number of patients or data variables. The subgroup percentage was calculated by using the number of patients or data available within the subgroup divided by the total number of patients in that subgroup.
In alone vs concomitant and completed vs discontinued treatment groups, a 2-tailed, 2-sample z test was used to statistical significance (P < .05) using a statistics website.70 Concomitant was defined as paclitaxel taken with other antineoplastic agent(s) before, after, or at the same time as cancer therapy. For the retrospective data analysis, physicians’ notes with a period, comma, forward slash, semicolon, or space between medication names were interpreted as concurrent, whereas plus (+), minus/plus (-/+), or “and” between drug names that were dispensed on the same day were interpreted as combined with known common combinations: 2 drugs (DM886 paclitaxel and carboplatin and DM881-TC-1 paclitaxel and cisplatin) or 3 drugs (DM887-ACT doxorubicin, cyclophosphamide, and paclitaxel). Completed treatment was defined as paclitaxel as the last medication the patient took without recorded AEs; switching or experiencing AEs was defined as discontinued treatment.
RESULTS
The JPC provided 702 entries for 687 patients with a mean age of 56 years (range, 2 months to 88 years) who were treated with paclitaxel from March 1996 to October 2021. Fifteen patients had duplicate entries because they had multiple cancer sites or occurrences. There were 623 patients (89%) who received paclitaxel for FDA-approved indications. The most common types of cancer identified were 344 patients with breast cancer (49%), 91 patients with lung cancer (13%), 79 patients with ovarian cancer (11%), and 75 patients with endometrial cancer (11%) (Table 1). Seventy-nine patients (11%) received paclitaxel for cancers that were not for FDA-approved indications, including 19 for cancers of the fallopian tube (3%) and 17 for esophageal cancer (2%) (Table 2).
There were 477 patients (68%) aged > 50 years. A total of 304 patients (43%) had a stage III or IV cancer diagnosis and 398 (57%) had stage II or lower (combination of data for stages 0, I, and II; not applicable; and unknown) cancer diagnosis. For systemic treatment, 16 patients (2%) were treated with paclitaxel alone and 686 patients (98%) received paclitaxel concomitantly with additional chemotherapy: 59 patients (9%) in the before or after group, 410 patients (58%) had a 2-drug combination, 212 patients (30%) had a 3-drug combination, and 5 patients (1%) had a 4-drug combination. In addition, for doublet therapies, paclitaxel combined with carboplatin, trastuzumab, gemcitabine, or cisplatin had more patients (318, 58, 12, and 11, respectively) than other combinations (≤ 4 patients). For triplet therapies, paclitaxel combined withdoxorubicin plus cyclophosphamide or carboplatin plus bevacizumab had more patients (174 and 20, respectively) than other combinations, including quadruplet therapies (≤ 4 patients) (Table 3).
Patients were more likely to discontinue paclitaxel if they received concomitant treatment. None of the 16 patients receiving paclitaxel monotherapy experienced AEs, whereas 364 of 686 patients (53%) treated concomitantly discontinued (P < .001). Comparisons of 1 drug vs combination (2 to 4 drugs) and use for treating cancers that were FDA-approved indications vs off-label use were significant (P < .001), whereas comparisons of stage II or lower vs stage III and IV cancer and of those aged ≤ 50 years vs aged > 50 years were not significant (P = .50 andP = .30, respectively) (Table 4).
Among the 364 patients who had concomitant treatment and had discontinued their treatment, 332 (91%) switched treatments with no AEs documented and 32 (9%) experienced fatigue with pneumonia, mucositis, neuropathy, neurotoxicity, neutropenia, pneumonitis, allergic or hypersensitivity reaction, or an unknown AE. Patients who discontinued treatment because of unknown AEs had a physician’s note that detailed progressive disease, a significant decline in performance status, and another unknown adverse effect due to a previous sinus tract infection and infectious colitis (Table 5).
Management Analysis and Reporting Tool Database
MHS data analysts provided data on diagnoses for 639 patients among 687 submitteddiagnoses, with 294 patients completing and 345 discontinuing paclitaxel treatment. Patients in the completed treatment group had 3 to 258 unique health conditions documented, while patients in the discontinued treatment group had 4 to 181 unique health conditions documented. The MHS reported 3808 unique diagnosis conditions for the completed group and 3714 for the discontinued group (P = .02).
The mean (SD) number of diagnoses was 51 (31) for the completed and 55 (28) for the discontinued treatment groups (Figure). Among 639 patients who received paclitaxel, the top 5 diagnoses were administrative, including encounters for other administrative examinations; antineoplastic chemotherapy; administrative examination for unspecified; other specified counseling; and adjustment and management of vascular access device. The database does not differentiate between administrative and clinically significant diagnoses.
MHS data analysts provided data for 336 of 687 submitted patients who were prescribed paclitaxel; 46 patients had no PDTS data, and 305 patients had PDTS data without paclitaxel, Taxol, or Abraxane dispensed. Medications that were filled outside the chemotherapy period were removed by evaluating the dispensed date and day of supply. Among these 336 patients, 151 completed the treatment and 185 discontinued, with 14 patients experiencing documented AEs. Patients in the completed treatment group filled 9 to 56 prescriptions while patients in the discontinued treatment group filled 6 to 70 prescriptions.Patients in the discontinued group filled more prescriptions than those who completed treatment: 793 vs 591, respectively (P = .34).
The mean (SD) number of filled prescription drugs was 24 (9) for the completed and 34 (12) for the discontinued treatment group. The 5 most filled prescriptions with paclitaxel from 336 patients with PDTS data were dexamethasone (324 prescriptions with 14 recorded AEs), diphenhydramine (296 prescriptions with 12 recorded AEs), ondansetron (277 prescriptions with 11 recorded AEs), prochlorperazine (265 prescriptions with 12 recorded AEs), and sodium chloride (232 prescriptions with 11 recorded AEs).
DISCUSSION
As a retrospective review, this study is more limited in the strength of its conclusions when compared to randomized control trials. The DoD Cancer Registry Program only contains information about cancer types, stages, treatment regimens, and physicians’ notes. Therefore, noncancer drugs are based solely on the PDTS database. In most cases, physicians' notes on AEs were not detailed. There was no distinction between initial vs later lines of therapy and dosage reductions. The change in status or appearance of a new medical condition did not indicate whether paclitaxel caused the changes to develop or directly worsen a pre-existing condition. The PDTS records prescriptions filled, but that may not reflect patients taking prescriptions.
Paclitaxel
Paclitaxel has a long list of both approved and off-label uses in malignancies as a primary agent and in conjunction with other drugs. The FDA prescribing information for Taxol and Abraxane was last updated in April 2011 and September 2020, respectively.20,21 The National Institutes of Health National Library of Medicine has the current update for paclitaxel on July 2023.19,22 Thus, the prescribed information for paclitaxel referenced in the database may not always be up to date. The combinations of paclitaxel with bevacizumab, carboplatin, or carboplatin and pembrolizumab were not in the Taxol prescribing information. Likewise, a combination of nab-paclitaxel with atezolizumab or carboplatin and pembrolizumab is missing in the Abraxane prescribing information.22-27
The generic name is not the same as a generic drug, which may have slight differences from the brand name product.71 The generic drug versions of Taxol and Abraxane have been approved by the FDA as paclitaxel injectable and paclitaxel-protein bound, respectively. There was a global shortage of nab-paclitaxel from October 2021 to June 2022 because of a manufacturing problem.72 During this shortage, data showed similar comments from physician documents that treatment switched to Taxol due to the Abraxane shortage.
Of 336 patients in the PDTS database with dispensed paclitaxel prescriptions, 276 received paclitaxel (year dispensed, 2013-2022), 27 received Abraxane (year dispensed, 2013-2022), 47 received Taxol (year dispensed, 2004-2015), 8 received both Abraxane and paclitaxel, and 6 received both Taxol and paclitaxel. Based on this information, it appears that the distinction between the drugs was not made in the PDTS until after 2015, 10 years after Abraxane received FDA approval. Abraxane was prescribed in the MHS in 2013, 8 years after FDA approval. There were a few comparison studies of Abraxane and Taxol.73-76
Safety and effectiveness in pediatric patients have not been established for paclitaxel. According to the DoD Cancer Registry Program, the youngest patient was aged 2 months. In 2021, this patient was diagnosed with corpus uteri and treated with carboplatin and Taxol in course 1; in course 2, the patient reacted to Taxol; in course 3, Taxol was replaced with Abraxane; in courses 4 to 7, the patient was treated with carboplatin only.
Discontinued Treatment
Ten patients had prescribed Taxol that was changed due to AEs: 1 was switched to Abraxane and atezolizumab, 3 switched to Abraxane, 2 switched to docetaxel, 1 switched to doxorubicin, and 3 switched to pembrolizumab (based on physician’s comments). Of the 10 patients, 7 had Taxol reaction, 2 experienced disease progression, and 1 experienced high programmed death–ligand 1 expression (this patient with breast cancer was switched to Abraxane and atezolizumab during the accelerated FDA approval phase for atezolizumab, which was later revoked). Five patients were treated with carboplatin and Taxol for cancer of the anal canal (changed to pembrolizumab after disease progression), lung not otherwise specified (changed to carboplatin and pembrolizumab due to Taxol reaction), lower inner quadrant of the breast (changed to doxorubicin due to hypersensitivity reaction), corpus uteri (changed to Abraxane due to Taxol reaction), and ovary (changed to docetaxel due to Taxol reaction). Three patients were treated with doxorubicin, cyclophosphamide, and Taxol for breast cancer; 2 patients with breast cancer not otherwise specified switched to Abraxane due to cardiopulmonary hypersensitivity and Taxol reaction and 1 patient with cancer of the upper outer quadrant of the breast changed to docetaxel due to allergic reaction. One patient, who was treated with paclitaxel, ifosfamide, and cisplatin for metastasis of the lower lobe of the lung and kidney cancer, experienced complications due to infectious colitis (treated with ciprofloxacin) and then switched to pembrolizumab after the disease progressed. These AEs are known in paclitaxel medical literature on paclitaxel AEs.19-24,77-81
Combining 2 or more treatments to target cancer-inducing or cell-sustaining pathways is a cornerstone of chemotherapy.82-84 Most combinations are given on the same day, but some are not. For 3- or 4-drug combinations, doxorubicin and cyclophosphamide were given first, followed by paclitaxel with or withouttrastuzumab, carboplatin, or pembrolizumab. Only 16 patients (2%) were treated with paclitaxel alone; therefore, the completed and discontinued treatment groups are mostly concomitant treatment. As a result, the comparisons of the completed and discontinued treatment groups were almost the same for the diagnosis. The PDTS data have a better result because 2 exclusion criteria were applied before narrowing the analysis down to paclitaxel treatment specifically.
Antidepressants and Other Drugs
Drug response can vary from person to person and can lead to treatment failure related to AEs. One major factor in drug metabolism is CYP.85 CYP2C8 is the major pathway for paclitaxel and CYP3A4 is the minor pathway. When evaluating the noncancer drugs, there were no reports of CYP2C8 inhibition or induction.Over the years, many DDI warnings have been issued for paclitaxel with different drugs in various electronic resources.
Oncologists follow guidelines to prevent DDIs, as paclitaxel is known to have severe, moderate, and minor interactions with other drugs. Among 687 patients, 261 (38%) were prescribed any of 14 antidepressants. Eight of these antidepressants (amitriptyline, citalopram, desipramine, doxepin, venlafaxine, escitalopram, nortriptyline, and trazodone) are metabolized, 3 (mirtazapine, sertraline, and fluoxetine) are metabolized and inhibited, 2 (bupropion and duloxetine) are neither metabolized nor inhibited, and 1 (paroxetine) is inhibited by CYP3A4. Duloxetine, venlafaxine, and trazodone were more commonly dispensed (84, 78, and 42 patients, respectively) than others (≤ 33 patients).
Of 32 patients with documented AEs,14 (44%) had 168 dispensed drugs in the PDTS database. Six patients (19%) were treated with doxorubicin and cyclophosphamide followed by paclitaxel for breast cancer; 6 (19%) were treated with carboplatin and paclitaxel for cancer of the lung (n = 3), corpus uteri (n = 2), and ovary (n = 1); 1 patient (3%) was treated with carboplatin and paclitaxel, then switched to carboplatin, bevacizumab, and paclitaxel, and then completed treatment with carboplatin and paclitaxel for an unspecified female genital cancer; and 1 patient (3%) was treated with cisplatin, ifosfamide, and paclitaxel for metastasis of the lower lobe lung and kidney cancer.
The 14 patients with PDTS data had 18 cancer drugs dispensed. Eleven had moderate interaction reports and 7 had no interaction reports. A total of 165 noncancer drugs were dispensed, of which 3 were antidepressants and had no interactions reported, 8 had moderate interactions reported, and 2 had minor interactions with Taxol and Abraxane, respectively (Table 6).86-129
Of 3 patients who were dispensed bupropion, nortriptyline, or paroxetine, 1 patient with breast cancer was treated with doxorubicin andcyclophosphamide, followed by paclitaxel with bupropion, nortriptyline, pegfilgrastim,dexamethasone, and 17 other noncancer drugs that had no interaction report dispensed during paclitaxel treatment. Of 2 patients with lung cancer, 1 patient was treated with carboplatin and paclitaxel with nortriptyline, dexamethasone, and 13 additional medications, and the second patient was treated with paroxetine, cimetidine, dexamethasone, and 12 other medications. Patients were dispensed up to6 noncancer medications on the same day as paclitaxel administration to control the AEs, not including the prodrugs filled before the treatments. Paroxetine and cimetidine have weak inhibition, and dexamethasone has weak induction of CYP3A4. Therefore, while 1:1 DDIs might have little or no effect with weak inhibit/induce CYP3A4 drugs, 1:1:1 or more combinations could have a different outcome (confirmed in previous publications).65-67
Dispensed on the same day may not mean taken at the same time. One patient experienced an AE with dispensed 50 mg losartan, carboplatin plus paclitaxel, dexamethasone, and 6 other noncancer drugs. Losartan inhibits paclitaxel, which can lead to negative AEs.57,66,67 However, there were no blood or plasma samples taken to confirm the losartan was taken at the same time as the paclitaxel given this was not a clinical trial.
Conclusions
This retrospective study discusses the use of paclitaxel in the MHS and the potential DDIs associated with it. The study population consisted mostly of active-duty personnel, who are required to be healthy or have controlled or nonactive medical diagnoses and be physically fit. This group is mixed with dependents and retirees that are more reflective of the average US population. As a result, this patient population is healthier than the general population, with a lower prevalence of common illnesses such as diabetes and obesity. The study aimed to identify drugs used alongside paclitaxel treatment. While further research is needed to identify potential DDIs among patients who experienced AEs, in vitro testing will need to be conducted before confirming causality. The low number of AEs experienced by only 32 of 702 patients (5%), with no deaths during paclitaxel treatment, indicates that the drug is generally well tolerated. Although this study cannot conclude that concomitant use with noncancer drugs led to the discontinuation of paclitaxel, we can conclude that there seems to be no significant DDIsidentified between paclitaxel and antidepressants. This comprehensive overview provides clinicians with a complete picture of paclitaxel use for 27 years (1996-2022), enabling them to make informed decisions about paclitaxel treatment.
Acknowledgments
The Department of Research Program funds at Walter Reed National Military Medical Center supported this protocol. We sincerely appreciate the contribution of data extraction from the Joint Pathology Center teams (Francisco J. Rentas, John D. McGeeney, Beatriz A. Hallo, and Johnny P. Beason) and the MHS database personnel (Maj Ryan Costantino, Brandon E. Jenkins, and Alexander G. Rittel). We gratefully thank you for the protocol support from the Department of Research programs: CDR Martin L. Boese, CDR Wesley R. Campbell, Maj. Abhimanyu Chandel, CDR Ling Ye, Chelsea N. Powers, Yaling Zhou, Elizabeth Schafer, Micah Stretch, Diane Beaner, and Adrienne Woodard.
Background
Paclitaxel was first derived from the bark of the yew tree (Taxus brevifolia). It was discovered as part of a National Cancer Institute program screen of plants and natural products with putative anticancer activity during the 1960s.1-9 Paclitaxel works by suppressing spindle microtube dynamics, which results in the blockage of the metaphase-anaphase transitions, inhibition of mitosis, and induction of apoptosis in a broad spectrum of cancer cells. Paclitaxel also displayed additional anticancer activities, including the suppression of cell proliferation and antiangiogenic effects. However, since the growth of normal body cells may also be affected, other adverse effects (AEs) will also occur.8-18
Two different chemotherapy drugs contain paclitaxel—paclitaxel and nab-paclitaxel—and the US Food and Drug Administration (FDA) recognizes them as separate entities.19-21 Taxol (paclitaxel) was approved by the FDA in 1992 for treating advanced ovarian cancer.20 It has since been approved for the treatment of metastatic breast cancer, AIDS-related Kaposi sarcoma (as an orphan drug), non-small cell lung cancer (NSCLC), and cervical cancers (in combination withbevacizumab) in 1994, 1997, 1999, and 2014, respectively.21 Since 2002, a generic version of Taxol, known as paclitaxel injectable, has been FDA-approved from different manufacturers. According to the National Cancer Institute, a combination of carboplatin and Taxol is approved to treat carcinoma of unknown primary, cervical, endometrial, NSCLC, ovarian, and thymoma cancers.19 Abraxane (nab-paclitaxel) was FDA-approved to treat metastatic breast cancer in 2005. It was later approved for first-line treatment of advanced NSCLC and late-stage pancreatic cancer in 2012 and 2013, respectively. In 2018 and 2020, both Taxol and Abraxane were approved for first-line treatment of metastatic squamous cell NSCLC in combination with carboplatin and pembrolizumab and metastatic triple-negative breast cancer in combination with pembrolizumab, respectively.22-26 In 2019, Abraxane was approved with atezolizumab to treat metastatic triple-negative breast cancer, but this approval was withdrawn in 2021. In 2022, a generic version of Abraxane, known as paclitaxel protein-bound, was released in the United States. Furthermore, paclitaxel-containing formulations also are being studied in the treatment of other types of cancer.19-32
One of the main limitations of paclitaxel is its low solubility in water, which complicates its drug supply. To distribute this hydrophobic anticancer drug efficiently, paclitaxel is formulated and administered to patients via polyethoxylated castor oil or albumin-bound (nab-paclitaxel). However, polyethoxylated castor oil induces complement activation and is the cause of common hypersensitivity reactions related to paclitaxel use.2,17,33-38 Therefore, many alternatives to polyethoxylated castor oil have been researched.
Since 2000, new paclitaxel formulations have emerged using nanomedicine techniques. The difference between these formulations is the drug vehicle. Different paclitaxel-based nanotechnological vehicles have been developed and approved, such as albumin-based nanoparticles, polymeric lipidic nanoparticles, polymeric micelles, and liposomes, with many others in clinical trial phases.3,37 Albumin-based nanoparticles have a high response rate (33%), whereas the response rate for polyethoxylated castor oil is 25% in patients with metastatic breast cancer.33,39-52 The use of paclitaxel dimer nanoparticles also has been proposed as a method for increasing drug solubility.33,53
Paclitaxel is metabolized by cytochrome P450 (CYP) isoenzymes 2C8 and 3A4. When administering paclitaxel with known inhibitors, inducers, or substrates of CYP2C8 or CYP3A4, caution is required.19-22 Regulations for CYP research were not issued until 2008, so potential interactions between paclitaxel and other drugs have not been extensively evaluated in clinical trials. A study of 12 kinase inhibitors showed strong inhibition of CYP2C8 and/or CYP3A4 pathways by these inhibitors, which could alter the ratio of paclitaxel metabolites in vivo, leading to clinically relevant changes.54 Differential metabolism has been linked to paclitaxel-induced neurotoxicity in patients with cancer.55 Nonetheless, variants in the CYP2C8, CYP3A4, CYP3A5, and ABCB1 genes do not account for significant interindividual variability in paclitaxel pharmacokinetics.56 In liver microsomes, losartan inhibited paclitaxel metabolism when used at concentrations > 50 µmol/L.57 Many drug-drug interaction (DDI) studies of CYP2C8 and CYP3A4 have shown similar results for paclitaxel.58-64
The goals of this study are to investigate prescribed drugs used with paclitaxel and determine patient outcomes through several Military Health System (MHS) databases. The investigation focused on (1) the functions of paclitaxel; (2) identifying AEs that patients experienced; (3) evaluating differences when paclitaxel is used alone vs concomitantly and between the completed vs discontinued treatment groups; (4) identifying all drugs used during paclitaxel treatment; and (5) evaluating DDIs with antidepressants (that have an FDA boxed warning and are known to have DDIs confirmed in previous publications) and other drugs.65-67
The Walter Reed National Military Medical Center in Bethesda, Maryland, institutionalreview board approved the study protocol and ensured compliance with the Health Insurance Portability and Accountability Act as an exempt protocol. The Joint Pathology Center (JPC) of the US Department of Defense (DoD) Cancer Registry Program and MHS data experts from the Comprehensive Ambulatory/Professional Encounter Record (CAPER) and the Pharmacy Data Transaction Service (PDTS) provided data for the analysis.
METHODS
The DoD Cancer Registry Program was established in 1986 and currently contains data from 1998 to 2024. CAPER and PDTS are part of the MHS Data Repository/Management Analysis and Reporting Tool database. Each observation in the CAPER record represents an ambulatory encounter at a military treatment facility (MTF). CAPER includes data from 2003 to 2024.
Each observation in the PDTS record represents a prescription filled for an MHS beneficiary at an MTF through the TRICARE mail-order program or a US retail pharmacy. Missing from this record are prescriptions filled at international civilian pharmacies and inpatient pharmacy prescriptions. The MHS Data Repository PDTS record is available from 2002 to 2024. The legacy Composite Health Care System is being replaced by GENESIS at MTFs.
Data Extraction Design
The study design involved a cross-sectional analysis. We requested data extraction for paclitaxel from 1998 to 2022. Data from the DoD Cancer Registry Program were used to identify patients who received cancer treatment. Once patients were identified, the CAPER database was searched for diagnoses to identify other health conditions, whereas the PDTS database was used to populate a list of prescription medications filled during chemotherapy treatment.
Data collected from the JPC included cancer treatment, cancer information, demographics, and physicians’ comments on AEs. Collected data from the MHS include diagnosis and filled prescription history from initiation to completion of the therapy period (or 2 years after the diagnosis date). For the analysis of the DoD Cancer Registry Program and CAPER databases, we used all collected data without excluding any. When analyzing PDTS data, we excluded patients with PDTS data but without a record of paclitaxel being filled, or medications filled outside the chemotherapy period (by evaluating the dispensed date and day of supply).
Data Extraction Analysis
The Surveillance, Epidemiology, and End Results Program Coding and Staging Manual 2016 and the International Classification of Diseases for Oncology, 3rd edition, 1st revision, were used to decode disease and cancer types.68,69 Data sorting and analysis were performed using Microsoft Excel. The percentage for the total was calculated by using the number of patients or data available within the paclitaxel groups divided by the total number of patients or data variables. The subgroup percentage was calculated by using the number of patients or data available within the subgroup divided by the total number of patients in that subgroup.
In alone vs concomitant and completed vs discontinued treatment groups, a 2-tailed, 2-sample z test was used to statistical significance (P < .05) using a statistics website.70 Concomitant was defined as paclitaxel taken with other antineoplastic agent(s) before, after, or at the same time as cancer therapy. For the retrospective data analysis, physicians’ notes with a period, comma, forward slash, semicolon, or space between medication names were interpreted as concurrent, whereas plus (+), minus/plus (-/+), or “and” between drug names that were dispensed on the same day were interpreted as combined with known common combinations: 2 drugs (DM886 paclitaxel and carboplatin and DM881-TC-1 paclitaxel and cisplatin) or 3 drugs (DM887-ACT doxorubicin, cyclophosphamide, and paclitaxel). Completed treatment was defined as paclitaxel as the last medication the patient took without recorded AEs; switching or experiencing AEs was defined as discontinued treatment.
RESULTS
The JPC provided 702 entries for 687 patients with a mean age of 56 years (range, 2 months to 88 years) who were treated with paclitaxel from March 1996 to October 2021. Fifteen patients had duplicate entries because they had multiple cancer sites or occurrences. There were 623 patients (89%) who received paclitaxel for FDA-approved indications. The most common types of cancer identified were 344 patients with breast cancer (49%), 91 patients with lung cancer (13%), 79 patients with ovarian cancer (11%), and 75 patients with endometrial cancer (11%) (Table 1). Seventy-nine patients (11%) received paclitaxel for cancers that were not for FDA-approved indications, including 19 for cancers of the fallopian tube (3%) and 17 for esophageal cancer (2%) (Table 2).
There were 477 patients (68%) aged > 50 years. A total of 304 patients (43%) had a stage III or IV cancer diagnosis and 398 (57%) had stage II or lower (combination of data for stages 0, I, and II; not applicable; and unknown) cancer diagnosis. For systemic treatment, 16 patients (2%) were treated with paclitaxel alone and 686 patients (98%) received paclitaxel concomitantly with additional chemotherapy: 59 patients (9%) in the before or after group, 410 patients (58%) had a 2-drug combination, 212 patients (30%) had a 3-drug combination, and 5 patients (1%) had a 4-drug combination. In addition, for doublet therapies, paclitaxel combined with carboplatin, trastuzumab, gemcitabine, or cisplatin had more patients (318, 58, 12, and 11, respectively) than other combinations (≤ 4 patients). For triplet therapies, paclitaxel combined withdoxorubicin plus cyclophosphamide or carboplatin plus bevacizumab had more patients (174 and 20, respectively) than other combinations, including quadruplet therapies (≤ 4 patients) (Table 3).
Patients were more likely to discontinue paclitaxel if they received concomitant treatment. None of the 16 patients receiving paclitaxel monotherapy experienced AEs, whereas 364 of 686 patients (53%) treated concomitantly discontinued (P < .001). Comparisons of 1 drug vs combination (2 to 4 drugs) and use for treating cancers that were FDA-approved indications vs off-label use were significant (P < .001), whereas comparisons of stage II or lower vs stage III and IV cancer and of those aged ≤ 50 years vs aged > 50 years were not significant (P = .50 andP = .30, respectively) (Table 4).
Among the 364 patients who had concomitant treatment and had discontinued their treatment, 332 (91%) switched treatments with no AEs documented and 32 (9%) experienced fatigue with pneumonia, mucositis, neuropathy, neurotoxicity, neutropenia, pneumonitis, allergic or hypersensitivity reaction, or an unknown AE. Patients who discontinued treatment because of unknown AEs had a physician’s note that detailed progressive disease, a significant decline in performance status, and another unknown adverse effect due to a previous sinus tract infection and infectious colitis (Table 5).
Management Analysis and Reporting Tool Database
MHS data analysts provided data on diagnoses for 639 patients among 687 submitteddiagnoses, with 294 patients completing and 345 discontinuing paclitaxel treatment. Patients in the completed treatment group had 3 to 258 unique health conditions documented, while patients in the discontinued treatment group had 4 to 181 unique health conditions documented. The MHS reported 3808 unique diagnosis conditions for the completed group and 3714 for the discontinued group (P = .02).
The mean (SD) number of diagnoses was 51 (31) for the completed and 55 (28) for the discontinued treatment groups (Figure). Among 639 patients who received paclitaxel, the top 5 diagnoses were administrative, including encounters for other administrative examinations; antineoplastic chemotherapy; administrative examination for unspecified; other specified counseling; and adjustment and management of vascular access device. The database does not differentiate between administrative and clinically significant diagnoses.
MHS data analysts provided data for 336 of 687 submitted patients who were prescribed paclitaxel; 46 patients had no PDTS data, and 305 patients had PDTS data without paclitaxel, Taxol, or Abraxane dispensed. Medications that were filled outside the chemotherapy period were removed by evaluating the dispensed date and day of supply. Among these 336 patients, 151 completed the treatment and 185 discontinued, with 14 patients experiencing documented AEs. Patients in the completed treatment group filled 9 to 56 prescriptions while patients in the discontinued treatment group filled 6 to 70 prescriptions.Patients in the discontinued group filled more prescriptions than those who completed treatment: 793 vs 591, respectively (P = .34).
The mean (SD) number of filled prescription drugs was 24 (9) for the completed and 34 (12) for the discontinued treatment group. The 5 most filled prescriptions with paclitaxel from 336 patients with PDTS data were dexamethasone (324 prescriptions with 14 recorded AEs), diphenhydramine (296 prescriptions with 12 recorded AEs), ondansetron (277 prescriptions with 11 recorded AEs), prochlorperazine (265 prescriptions with 12 recorded AEs), and sodium chloride (232 prescriptions with 11 recorded AEs).
DISCUSSION
As a retrospective review, this study is more limited in the strength of its conclusions when compared to randomized control trials. The DoD Cancer Registry Program only contains information about cancer types, stages, treatment regimens, and physicians’ notes. Therefore, noncancer drugs are based solely on the PDTS database. In most cases, physicians' notes on AEs were not detailed. There was no distinction between initial vs later lines of therapy and dosage reductions. The change in status or appearance of a new medical condition did not indicate whether paclitaxel caused the changes to develop or directly worsen a pre-existing condition. The PDTS records prescriptions filled, but that may not reflect patients taking prescriptions.
Paclitaxel
Paclitaxel has a long list of both approved and off-label uses in malignancies as a primary agent and in conjunction with other drugs. The FDA prescribing information for Taxol and Abraxane was last updated in April 2011 and September 2020, respectively.20,21 The National Institutes of Health National Library of Medicine has the current update for paclitaxel on July 2023.19,22 Thus, the prescribed information for paclitaxel referenced in the database may not always be up to date. The combinations of paclitaxel with bevacizumab, carboplatin, or carboplatin and pembrolizumab were not in the Taxol prescribing information. Likewise, a combination of nab-paclitaxel with atezolizumab or carboplatin and pembrolizumab is missing in the Abraxane prescribing information.22-27
The generic name is not the same as a generic drug, which may have slight differences from the brand name product.71 The generic drug versions of Taxol and Abraxane have been approved by the FDA as paclitaxel injectable and paclitaxel-protein bound, respectively. There was a global shortage of nab-paclitaxel from October 2021 to June 2022 because of a manufacturing problem.72 During this shortage, data showed similar comments from physician documents that treatment switched to Taxol due to the Abraxane shortage.
Of 336 patients in the PDTS database with dispensed paclitaxel prescriptions, 276 received paclitaxel (year dispensed, 2013-2022), 27 received Abraxane (year dispensed, 2013-2022), 47 received Taxol (year dispensed, 2004-2015), 8 received both Abraxane and paclitaxel, and 6 received both Taxol and paclitaxel. Based on this information, it appears that the distinction between the drugs was not made in the PDTS until after 2015, 10 years after Abraxane received FDA approval. Abraxane was prescribed in the MHS in 2013, 8 years after FDA approval. There were a few comparison studies of Abraxane and Taxol.73-76
Safety and effectiveness in pediatric patients have not been established for paclitaxel. According to the DoD Cancer Registry Program, the youngest patient was aged 2 months. In 2021, this patient was diagnosed with corpus uteri and treated with carboplatin and Taxol in course 1; in course 2, the patient reacted to Taxol; in course 3, Taxol was replaced with Abraxane; in courses 4 to 7, the patient was treated with carboplatin only.
Discontinued Treatment
Ten patients had prescribed Taxol that was changed due to AEs: 1 was switched to Abraxane and atezolizumab, 3 switched to Abraxane, 2 switched to docetaxel, 1 switched to doxorubicin, and 3 switched to pembrolizumab (based on physician’s comments). Of the 10 patients, 7 had Taxol reaction, 2 experienced disease progression, and 1 experienced high programmed death–ligand 1 expression (this patient with breast cancer was switched to Abraxane and atezolizumab during the accelerated FDA approval phase for atezolizumab, which was later revoked). Five patients were treated with carboplatin and Taxol for cancer of the anal canal (changed to pembrolizumab after disease progression), lung not otherwise specified (changed to carboplatin and pembrolizumab due to Taxol reaction), lower inner quadrant of the breast (changed to doxorubicin due to hypersensitivity reaction), corpus uteri (changed to Abraxane due to Taxol reaction), and ovary (changed to docetaxel due to Taxol reaction). Three patients were treated with doxorubicin, cyclophosphamide, and Taxol for breast cancer; 2 patients with breast cancer not otherwise specified switched to Abraxane due to cardiopulmonary hypersensitivity and Taxol reaction and 1 patient with cancer of the upper outer quadrant of the breast changed to docetaxel due to allergic reaction. One patient, who was treated with paclitaxel, ifosfamide, and cisplatin for metastasis of the lower lobe of the lung and kidney cancer, experienced complications due to infectious colitis (treated with ciprofloxacin) and then switched to pembrolizumab after the disease progressed. These AEs are known in paclitaxel medical literature on paclitaxel AEs.19-24,77-81
Combining 2 or more treatments to target cancer-inducing or cell-sustaining pathways is a cornerstone of chemotherapy.82-84 Most combinations are given on the same day, but some are not. For 3- or 4-drug combinations, doxorubicin and cyclophosphamide were given first, followed by paclitaxel with or withouttrastuzumab, carboplatin, or pembrolizumab. Only 16 patients (2%) were treated with paclitaxel alone; therefore, the completed and discontinued treatment groups are mostly concomitant treatment. As a result, the comparisons of the completed and discontinued treatment groups were almost the same for the diagnosis. The PDTS data have a better result because 2 exclusion criteria were applied before narrowing the analysis down to paclitaxel treatment specifically.
Antidepressants and Other Drugs
Drug response can vary from person to person and can lead to treatment failure related to AEs. One major factor in drug metabolism is CYP.85 CYP2C8 is the major pathway for paclitaxel and CYP3A4 is the minor pathway. When evaluating the noncancer drugs, there were no reports of CYP2C8 inhibition or induction.Over the years, many DDI warnings have been issued for paclitaxel with different drugs in various electronic resources.
Oncologists follow guidelines to prevent DDIs, as paclitaxel is known to have severe, moderate, and minor interactions with other drugs. Among 687 patients, 261 (38%) were prescribed any of 14 antidepressants. Eight of these antidepressants (amitriptyline, citalopram, desipramine, doxepin, venlafaxine, escitalopram, nortriptyline, and trazodone) are metabolized, 3 (mirtazapine, sertraline, and fluoxetine) are metabolized and inhibited, 2 (bupropion and duloxetine) are neither metabolized nor inhibited, and 1 (paroxetine) is inhibited by CYP3A4. Duloxetine, venlafaxine, and trazodone were more commonly dispensed (84, 78, and 42 patients, respectively) than others (≤ 33 patients).
Of 32 patients with documented AEs,14 (44%) had 168 dispensed drugs in the PDTS database. Six patients (19%) were treated with doxorubicin and cyclophosphamide followed by paclitaxel for breast cancer; 6 (19%) were treated with carboplatin and paclitaxel for cancer of the lung (n = 3), corpus uteri (n = 2), and ovary (n = 1); 1 patient (3%) was treated with carboplatin and paclitaxel, then switched to carboplatin, bevacizumab, and paclitaxel, and then completed treatment with carboplatin and paclitaxel for an unspecified female genital cancer; and 1 patient (3%) was treated with cisplatin, ifosfamide, and paclitaxel for metastasis of the lower lobe lung and kidney cancer.
The 14 patients with PDTS data had 18 cancer drugs dispensed. Eleven had moderate interaction reports and 7 had no interaction reports. A total of 165 noncancer drugs were dispensed, of which 3 were antidepressants and had no interactions reported, 8 had moderate interactions reported, and 2 had minor interactions with Taxol and Abraxane, respectively (Table 6).86-129
Of 3 patients who were dispensed bupropion, nortriptyline, or paroxetine, 1 patient with breast cancer was treated with doxorubicin andcyclophosphamide, followed by paclitaxel with bupropion, nortriptyline, pegfilgrastim,dexamethasone, and 17 other noncancer drugs that had no interaction report dispensed during paclitaxel treatment. Of 2 patients with lung cancer, 1 patient was treated with carboplatin and paclitaxel with nortriptyline, dexamethasone, and 13 additional medications, and the second patient was treated with paroxetine, cimetidine, dexamethasone, and 12 other medications. Patients were dispensed up to6 noncancer medications on the same day as paclitaxel administration to control the AEs, not including the prodrugs filled before the treatments. Paroxetine and cimetidine have weak inhibition, and dexamethasone has weak induction of CYP3A4. Therefore, while 1:1 DDIs might have little or no effect with weak inhibit/induce CYP3A4 drugs, 1:1:1 or more combinations could have a different outcome (confirmed in previous publications).65-67
Dispensed on the same day may not mean taken at the same time. One patient experienced an AE with dispensed 50 mg losartan, carboplatin plus paclitaxel, dexamethasone, and 6 other noncancer drugs. Losartan inhibits paclitaxel, which can lead to negative AEs.57,66,67 However, there were no blood or plasma samples taken to confirm the losartan was taken at the same time as the paclitaxel given this was not a clinical trial.
Conclusions
This retrospective study discusses the use of paclitaxel in the MHS and the potential DDIs associated with it. The study population consisted mostly of active-duty personnel, who are required to be healthy or have controlled or nonactive medical diagnoses and be physically fit. This group is mixed with dependents and retirees that are more reflective of the average US population. As a result, this patient population is healthier than the general population, with a lower prevalence of common illnesses such as diabetes and obesity. The study aimed to identify drugs used alongside paclitaxel treatment. While further research is needed to identify potential DDIs among patients who experienced AEs, in vitro testing will need to be conducted before confirming causality. The low number of AEs experienced by only 32 of 702 patients (5%), with no deaths during paclitaxel treatment, indicates that the drug is generally well tolerated. Although this study cannot conclude that concomitant use with noncancer drugs led to the discontinuation of paclitaxel, we can conclude that there seems to be no significant DDIsidentified between paclitaxel and antidepressants. This comprehensive overview provides clinicians with a complete picture of paclitaxel use for 27 years (1996-2022), enabling them to make informed decisions about paclitaxel treatment.
Acknowledgments
The Department of Research Program funds at Walter Reed National Military Medical Center supported this protocol. We sincerely appreciate the contribution of data extraction from the Joint Pathology Center teams (Francisco J. Rentas, John D. McGeeney, Beatriz A. Hallo, and Johnny P. Beason) and the MHS database personnel (Maj Ryan Costantino, Brandon E. Jenkins, and Alexander G. Rittel). We gratefully thank you for the protocol support from the Department of Research programs: CDR Martin L. Boese, CDR Wesley R. Campbell, Maj. Abhimanyu Chandel, CDR Ling Ye, Chelsea N. Powers, Yaling Zhou, Elizabeth Schafer, Micah Stretch, Diane Beaner, and Adrienne Woodard.
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