Metastatic Breast Cancer

Lillie Shockney, RN, MAS, a two-time breast cancer survivor and adjunct professor at Johns Hopkins School of Nursing in Baltimore, Maryland, mourns the many losses that her patients with advanced cancer now face in the midst of the COVID-19 pandemic. But in the void of the usual support networks and treatment plans, she sees the resurgence of something that has recently been crowded out: hospice.

The pandemic has forced patients and their physicians to reassess the risk/benefit balance of continuing or embarking on yet another cancer treatment.

“It’s one of the pearls that we will get out of this nightmare,” said Ms. Shockney, who recently retired as administrative director of the cancer survivorship programs at the Sidney Kimmel Comprehensive Cancer Center.

“Physicians have been taught to treat the disease – so as long as there’s a treatment they give another treatment,” she told Medscape Medical News during a Zoom call from her home. “But for some patients with advanced disease, those treatments were making them very sick, so they were trading longevity over quality of life.”

Of course, longevity has never been a guarantee with cancer treatment, and even less so now, with the risk of COVID-19.

“This is going to bring them to some hard discussions,” says Brenda Nevidjon, RN, MSN, chief executive officer at the Oncology Nursing Society.

“We’ve known for a long time that there are patients who are on third- and fourth-round treatment options that have very little evidence of prolonging life or quality of life,” she told Medscape Medical News. “Do we bring these people out of their home to a setting where there could be a fair number of COVID-positive patients? Do we expose them to that?”

Across the world, these dilemmas are pushing cancer specialists to initiate discussions of hospice sooner with patients who have advanced disease, and with more clarity than before.

One of the reasons such conversations have often been avoided is that the concept of hospice is generally misunderstood, said Ms. Shockney.

“Patients think ‘you’re giving up on me, you’ve abandoned me’, but hospice is all about preserving the remainder of their quality of life and letting them have time with family and time to fulfill those elements of experiencing a good and peaceful death,” she said.

Indeed, hospice is “a benefit meant for somebody with at least a 6-month horizon,” agrees Ms. Nevidjon. Yet the average length of hospice in the United States is just 5 days. “It’s at the very, very end, and yet for some of these patients the 6 months they could get in hospice might be a better quality of life than the 4 months on another whole plan of chemotherapy. I can’t imagine that on the backside of this pandemic we will not have learned and we won’t start to change practices around initiating more of these conversations.”
 

Silver lining of this pandemic?

It’s too early into the pandemic to have hard data on whether hospice uptake has increased, but “it’s encouraging to hear that hospice is being discussed and offered sooner as an alternative to that third- or fourth-round chemo,” said Lori Bishop, MHA, RN, vice president of palliative and advanced care at the National Hospice and Palliative Care Organization.

“I agree that improving informed-decision discussions and timely access to hospice is a silver lining of the pandemic,” she told Medscape Medical News.

But she points out that today’s hospice looks quite different than it did before the pandemic, with the immediate and very obvious difference being telehealth, which was not widely utilized previously.

In March, the Centers for Medicare & Medicaid Services expanded telehealth options for hospice providers, something that Ms. Bishop and other hospice providers hope will remain in place after the pandemic passes.

“Telehealth visits are offered to replace some in-home visits both to minimize risk of exposure to COVID-19 and reduce the drain on personal protective equipment,” Bishop explained.

“In-patient hospice programs are also finding unique ways to provide support and connect patients to their loved ones: visitors are allowed but limited to one or two. Music and pet therapy are being provided through the window or virtually and devices such as iPads are being used to help patients connect with loved ones,” she said.

Telehealth links patients out of loneliness, but the one thing it cannot do is provide the comfort of touch – an important part of any hospice program.

“Hand-holding ... I miss that a lot,” says Ms. Shockney, her eyes filling with tears. “When you take somebody’s hand, you don’t even have to speak; that connection, and eye contact, is all you need to help that person emotionally heal.”

This article first appeared on Medscape.com.

Lillie Shockney, RN, MAS, a two-time breast cancer survivor and adjunct professor at Johns Hopkins School of Nursing in Baltimore, Maryland, mourns the many losses that her patients with advanced cancer now face in the midst of the COVID-19 pandemic. But in the void of the usual support networks and treatment plans, she sees the resurgence of something that has recently been crowded out: hospice.

The pandemic has forced patients and their physicians to reassess the risk/benefit balance of continuing or embarking on yet another cancer treatment.

“It’s one of the pearls that we will get out of this nightmare,” said Ms. Shockney, who recently retired as administrative director of the cancer survivorship programs at the Sidney Kimmel Comprehensive Cancer Center.

“Physicians have been taught to treat the disease – so as long as there’s a treatment they give another treatment,” she told Medscape Medical News during a Zoom call from her home. “But for some patients with advanced disease, those treatments were making them very sick, so they were trading longevity over quality of life.”

Of course, longevity has never been a guarantee with cancer treatment, and even less so now, with the risk of COVID-19.

“This is going to bring them to some hard discussions,” says Brenda Nevidjon, RN, MSN, chief executive officer at the Oncology Nursing Society.

“We’ve known for a long time that there are patients who are on third- and fourth-round treatment options that have very little evidence of prolonging life or quality of life,” she told Medscape Medical News. “Do we bring these people out of their home to a setting where there could be a fair number of COVID-positive patients? Do we expose them to that?”

Across the world, these dilemmas are pushing cancer specialists to initiate discussions of hospice sooner with patients who have advanced disease, and with more clarity than before.

One of the reasons such conversations have often been avoided is that the concept of hospice is generally misunderstood, said Ms. Shockney.

“Patients think ‘you’re giving up on me, you’ve abandoned me’, but hospice is all about preserving the remainder of their quality of life and letting them have time with family and time to fulfill those elements of experiencing a good and peaceful death,” she said.

Indeed, hospice is “a benefit meant for somebody with at least a 6-month horizon,” agrees Ms. Nevidjon. Yet the average length of hospice in the United States is just 5 days. “It’s at the very, very end, and yet for some of these patients the 6 months they could get in hospice might be a better quality of life than the 4 months on another whole plan of chemotherapy. I can’t imagine that on the backside of this pandemic we will not have learned and we won’t start to change practices around initiating more of these conversations.”
 

Silver lining of this pandemic?

It’s too early into the pandemic to have hard data on whether hospice uptake has increased, but “it’s encouraging to hear that hospice is being discussed and offered sooner as an alternative to that third- or fourth-round chemo,” said Lori Bishop, MHA, RN, vice president of palliative and advanced care at the National Hospice and Palliative Care Organization.

“I agree that improving informed-decision discussions and timely access to hospice is a silver lining of the pandemic,” she told Medscape Medical News.

But she points out that today’s hospice looks quite different than it did before the pandemic, with the immediate and very obvious difference being telehealth, which was not widely utilized previously.

In March, the Centers for Medicare & Medicaid Services expanded telehealth options for hospice providers, something that Ms. Bishop and other hospice providers hope will remain in place after the pandemic passes.

“Telehealth visits are offered to replace some in-home visits both to minimize risk of exposure to COVID-19 and reduce the drain on personal protective equipment,” Bishop explained.

“In-patient hospice programs are also finding unique ways to provide support and connect patients to their loved ones: visitors are allowed but limited to one or two. Music and pet therapy are being provided through the window or virtually and devices such as iPads are being used to help patients connect with loved ones,” she said.

Telehealth links patients out of loneliness, but the one thing it cannot do is provide the comfort of touch – an important part of any hospice program.

“Hand-holding ... I miss that a lot,” says Ms. Shockney, her eyes filling with tears. “When you take somebody’s hand, you don’t even have to speak; that connection, and eye contact, is all you need to help that person emotionally heal.”

This article first appeared on Medscape.com.

Lillie Shockney, RN, MAS, a two-time breast cancer survivor and adjunct professor at Johns Hopkins School of Nursing in Baltimore, Maryland, mourns the many losses that her patients with advanced cancer now face in the midst of the COVID-19 pandemic. But in the void of the usual support networks and treatment plans, she sees the resurgence of something that has recently been crowded out: hospice.

The pandemic has forced patients and their physicians to reassess the risk/benefit balance of continuing or embarking on yet another cancer treatment.

“It’s one of the pearls that we will get out of this nightmare,” said Ms. Shockney, who recently retired as administrative director of the cancer survivorship programs at the Sidney Kimmel Comprehensive Cancer Center.

“Physicians have been taught to treat the disease – so as long as there’s a treatment they give another treatment,” she told Medscape Medical News during a Zoom call from her home. “But for some patients with advanced disease, those treatments were making them very sick, so they were trading longevity over quality of life.”

Of course, longevity has never been a guarantee with cancer treatment, and even less so now, with the risk of COVID-19.

“This is going to bring them to some hard discussions,” says Brenda Nevidjon, RN, MSN, chief executive officer at the Oncology Nursing Society.

“We’ve known for a long time that there are patients who are on third- and fourth-round treatment options that have very little evidence of prolonging life or quality of life,” she told Medscape Medical News. “Do we bring these people out of their home to a setting where there could be a fair number of COVID-positive patients? Do we expose them to that?”

Across the world, these dilemmas are pushing cancer specialists to initiate discussions of hospice sooner with patients who have advanced disease, and with more clarity than before.

One of the reasons such conversations have often been avoided is that the concept of hospice is generally misunderstood, said Ms. Shockney.

“Patients think ‘you’re giving up on me, you’ve abandoned me’, but hospice is all about preserving the remainder of their quality of life and letting them have time with family and time to fulfill those elements of experiencing a good and peaceful death,” she said.

Indeed, hospice is “a benefit meant for somebody with at least a 6-month horizon,” agrees Ms. Nevidjon. Yet the average length of hospice in the United States is just 5 days. “It’s at the very, very end, and yet for some of these patients the 6 months they could get in hospice might be a better quality of life than the 4 months on another whole plan of chemotherapy. I can’t imagine that on the backside of this pandemic we will not have learned and we won’t start to change practices around initiating more of these conversations.”
 

Silver lining of this pandemic?

It’s too early into the pandemic to have hard data on whether hospice uptake has increased, but “it’s encouraging to hear that hospice is being discussed and offered sooner as an alternative to that third- or fourth-round chemo,” said Lori Bishop, MHA, RN, vice president of palliative and advanced care at the National Hospice and Palliative Care Organization.

“I agree that improving informed-decision discussions and timely access to hospice is a silver lining of the pandemic,” she told Medscape Medical News.

But she points out that today’s hospice looks quite different than it did before the pandemic, with the immediate and very obvious difference being telehealth, which was not widely utilized previously.

In March, the Centers for Medicare & Medicaid Services expanded telehealth options for hospice providers, something that Ms. Bishop and other hospice providers hope will remain in place after the pandemic passes.

“Telehealth visits are offered to replace some in-home visits both to minimize risk of exposure to COVID-19 and reduce the drain on personal protective equipment,” Bishop explained.

“In-patient hospice programs are also finding unique ways to provide support and connect patients to their loved ones: visitors are allowed but limited to one or two. Music and pet therapy are being provided through the window or virtually and devices such as iPads are being used to help patients connect with loved ones,” she said.

Telehealth links patients out of loneliness, but the one thing it cannot do is provide the comfort of touch – an important part of any hospice program.

“Hand-holding ... I miss that a lot,” says Ms. Shockney, her eyes filling with tears. “When you take somebody’s hand, you don’t even have to speak; that connection, and eye contact, is all you need to help that person emotionally heal.”

This article first appeared on Medscape.com.

In an update of the PREDIX-HER2 trial, trastuzumab emtansine (T-DM1) remained equivalent to standard neoadjuvant chemotherapy plus dual-targeted HER2 therapy in producing pathologic complete remissions (pCRs) among patients with HER2-positive, metastatic breast cancer.

The new data also suggest tumor-infiltrating lymphocytes (TILs) and dramatic improvements in PET-CT scans can predict favorable outcomes in both treatment groups. Though these findings will be useful for research purposes, they likely won’t influence routine clinical practice.

Thomas Hatschek, MD, PhD, of Karolinska Institutet in Stockholm, presented the updated results from PREDIX-HER2 during the European Society for Medical Oncology: Breast Cancer virtual meeting.

PREDIX-HER2 included patients with HER2-positive breast cancer and tumor size greater than 20 mm or lymph node metastases.

Patients received neoadjuvant therapy (NAT) with docetaxel and trastuzumab plus pertuzumab (DTP) or T-DM1 every 3 weeks for a planned total of six courses. The protocol permitted switching to the competing treatment for progression, lack of response, or drug-related severe toxicity.

Postoperatively, all patients received triweekly epirubicin plus cyclophosphamide – four courses for the T-DM1 arm and two courses for the DTP arm. All patients then received triweekly adjuvant trastuzumab for 11 courses. The 62% of patients whose tumors were hormone receptor (HR)–positive received standard endocrine therapy postoperatively.
 

Updated results, predictors of pCR

At the 2019 ASCO annual meeting, PREDIX-HER2 investigators reported that, when compared with DTP, T-DM1 produced the same likelihood of pCR with less toxicity (ASCO 2019, Abstract 501). Updated data presented at ESMO Breast Cancer 2020 showed similar results.

The pCR rate was 45.5% in the DTP arm and 43.9% in the T-DM1 arm (P = .824). pCR rates were higher for HR-negative tumors – 63.6% in the DTP arm and 59% in the T-DM1 arm – than for HR-positive tumors – 36.4% in the DTP arm and 33.9% in the TDM-1 arm.

Three patients had disease progression with T-DM1, and none progressed with DTP. However, almost twice as many patients switched from DTP to T-DM1, compared with the other sequence.

Dr. Hatschek reported that the presence of at least 10% TILs predicted pCR in both treatment groups. Among patients who achieved a pCR, 52.2% had at least 10% TILs in baseline biopsies, and 30.4% had less than 10% TILs.

In addition, a decrease of FDG maximum standardized uptake value by more than 75% on protocol-required PET-CT scans was highly predictive of pCR. Among patients who achieved a pCR, 70.3% had a maximum standardized uptake value decrease of more than 75%, and 22.5% had a decrease of 75% or less.

At median follow-up of 28.5 months, event-free survival was similar between the treatment arms. Overall, there were 13 cases of progression, relapse, contralateral breast cancer, distant metastases, or death from any cause. There were five such events in the DTP arm and eight in the TDM-1 arm.

Dr. Hatschek concluded that neoadjuvant T-DM1 may be as effective as standard NAT in all clinical subgroups evaluated. Both TILs and PET-CT showed the potential to predict pCR and merit further study in the NAT setting.
 

An imperfect surrogate

By definition, a surrogate is “one appointed to act in place of another.” In the case of PREDIX-HER2 and most other NAT studies in HER2-positive breast cancer patients, pCR is a surrogate for the endpoint about which doctors and patients really care – cancer-free survival.

As such, pCR is not a perfect surrogate. Reproducibly, pCR has been highly predictive of disease-free survival and overall survival, especially in the HR-negative subset of HER2-positive patients.

However, despite improvements with dual targeting of HER2 in the TRYPHAENA trial (Eur J Cancer. 2018;89:27-35) and the use of T-DM1 for patients failing to achieve pCR in the immediately practice-changing KATHERINE trial (N Engl J Med. 2019;380:617-28), eventual relapse is seen in 10%-20% of patients in various clinical-pathologic subgroups.

In PREDIX-HER2, the pCR rate for node-positive patients was considerably lower with T-DM1 than with DTP (54.1% vs. 38%), noted Valentina Guarneri, MD, of the University of Padova (Italy), in her discussion of the trial at ESMO Breast Cancer 2020.

Patients with larger initial tumor size and multiple involved axillary nodes at diagnosis remain at increased risk of death because of cancer relapse.

Central nervous system relapse remains a vexing problem. Among patients with triple-positive breast cancer, relapses may occur late, despite pCR.

Patients whose tumors transform from HER2 positive to HER2 negative with NAT, seen in approximately 8% of cases in the KATHERINE trial (ESMO Breast Cancer 2020, Abstract 96O), may be another poor-risk group.
 

Clinical implications

PREDIX-HER2 is an important study. At the early time point of 2.4 years (especially early since most patients were HR-positive), if pCR is achieved, event-free survival is excellent with T-DM1 or an aggressive multiagent cytotoxic combination plus dual HER2 targeting followed by anthracyclines.

It is ideal to have clinical-pathologic tests to distinguish those patients destined to achieve the surrogate endpoint of pCR from those who will not achieve it.

Despite linkage of TILs to improved outcome for triple-negative and HER2-enriched molecular subtypes (Lancet Oncol. 2018 Jan;19[1]:40-50), analysis of TILs is not standard practice in HER2-positive breast cancer in community settings. Optimal cutoffs are not well established, and TILs have not been linked to the choice of particular treatment options.

Currently, PET-CT scans are not part of National Comprehensive Cancer Network guidelines for pretreatment evaluation, except in patients for whom there is clinical suspicion of distant disease.

For those reasons, the main results of PREDIX-HER2 remain research tools that will focus our attention on the clinical-pathologic correlations Dr. Hatschek highlighted, but the results should have no influence on routine clinical practice at this time.

PREDIX-HER2 was funded by the Swedish Cancer Society, Radiumhemmet of Karolinska Institutet, Region Stockholm, and Roche Sweden. Dr. Hatschek disclosed relationships with Roche Sweden, Pfizer Sweden, and Pierre Fabre Sweden. Dr. Guarneri disclosed relationships with Roche, Novartis, and Eli Lilly.

Dr. Lyss was a community-based medical oncologist and clinical researcher for more than 35 years before his recent retirement. His clinical and research interests were focused on breast and lung cancers as well as expanding clinical trial access to medically underserved populations. He is based in St. Louis. He has no conflicts of interest.

SOURCE: Hatschek T et al. ESMO Breast Cancer 2020, Abstract 97O.

In an update of the PREDIX-HER2 trial, trastuzumab emtansine (T-DM1) remained equivalent to standard neoadjuvant chemotherapy plus dual-targeted HER2 therapy in producing pathologic complete remissions (pCRs) among patients with HER2-positive, metastatic breast cancer.

The new data also suggest tumor-infiltrating lymphocytes (TILs) and dramatic improvements in PET-CT scans can predict favorable outcomes in both treatment groups. Though these findings will be useful for research purposes, they likely won’t influence routine clinical practice.

Thomas Hatschek, MD, PhD, of Karolinska Institutet in Stockholm, presented the updated results from PREDIX-HER2 during the European Society for Medical Oncology: Breast Cancer virtual meeting.

PREDIX-HER2 included patients with HER2-positive breast cancer and tumor size greater than 20 mm or lymph node metastases.

Patients received neoadjuvant therapy (NAT) with docetaxel and trastuzumab plus pertuzumab (DTP) or T-DM1 every 3 weeks for a planned total of six courses. The protocol permitted switching to the competing treatment for progression, lack of response, or drug-related severe toxicity.

Postoperatively, all patients received triweekly epirubicin plus cyclophosphamide – four courses for the T-DM1 arm and two courses for the DTP arm. All patients then received triweekly adjuvant trastuzumab for 11 courses. The 62% of patients whose tumors were hormone receptor (HR)–positive received standard endocrine therapy postoperatively.
 

Updated results, predictors of pCR

At the 2019 ASCO annual meeting, PREDIX-HER2 investigators reported that, when compared with DTP, T-DM1 produced the same likelihood of pCR with less toxicity (ASCO 2019, Abstract 501). Updated data presented at ESMO Breast Cancer 2020 showed similar results.

The pCR rate was 45.5% in the DTP arm and 43.9% in the T-DM1 arm (P = .824). pCR rates were higher for HR-negative tumors – 63.6% in the DTP arm and 59% in the T-DM1 arm – than for HR-positive tumors – 36.4% in the DTP arm and 33.9% in the TDM-1 arm.

Three patients had disease progression with T-DM1, and none progressed with DTP. However, almost twice as many patients switched from DTP to T-DM1, compared with the other sequence.

Dr. Hatschek reported that the presence of at least 10% TILs predicted pCR in both treatment groups. Among patients who achieved a pCR, 52.2% had at least 10% TILs in baseline biopsies, and 30.4% had less than 10% TILs.

In addition, a decrease of FDG maximum standardized uptake value by more than 75% on protocol-required PET-CT scans was highly predictive of pCR. Among patients who achieved a pCR, 70.3% had a maximum standardized uptake value decrease of more than 75%, and 22.5% had a decrease of 75% or less.

At median follow-up of 28.5 months, event-free survival was similar between the treatment arms. Overall, there were 13 cases of progression, relapse, contralateral breast cancer, distant metastases, or death from any cause. There were five such events in the DTP arm and eight in the TDM-1 arm.

Dr. Hatschek concluded that neoadjuvant T-DM1 may be as effective as standard NAT in all clinical subgroups evaluated. Both TILs and PET-CT showed the potential to predict pCR and merit further study in the NAT setting.
 

An imperfect surrogate

By definition, a surrogate is “one appointed to act in place of another.” In the case of PREDIX-HER2 and most other NAT studies in HER2-positive breast cancer patients, pCR is a surrogate for the endpoint about which doctors and patients really care – cancer-free survival.

As such, pCR is not a perfect surrogate. Reproducibly, pCR has been highly predictive of disease-free survival and overall survival, especially in the HR-negative subset of HER2-positive patients.

However, despite improvements with dual targeting of HER2 in the TRYPHAENA trial (Eur J Cancer. 2018;89:27-35) and the use of T-DM1 for patients failing to achieve pCR in the immediately practice-changing KATHERINE trial (N Engl J Med. 2019;380:617-28), eventual relapse is seen in 10%-20% of patients in various clinical-pathologic subgroups.

In PREDIX-HER2, the pCR rate for node-positive patients was considerably lower with T-DM1 than with DTP (54.1% vs. 38%), noted Valentina Guarneri, MD, of the University of Padova (Italy), in her discussion of the trial at ESMO Breast Cancer 2020.

Patients with larger initial tumor size and multiple involved axillary nodes at diagnosis remain at increased risk of death because of cancer relapse.

Central nervous system relapse remains a vexing problem. Among patients with triple-positive breast cancer, relapses may occur late, despite pCR.

Patients whose tumors transform from HER2 positive to HER2 negative with NAT, seen in approximately 8% of cases in the KATHERINE trial (ESMO Breast Cancer 2020, Abstract 96O), may be another poor-risk group.
 

Clinical implications

PREDIX-HER2 is an important study. At the early time point of 2.4 years (especially early since most patients were HR-positive), if pCR is achieved, event-free survival is excellent with T-DM1 or an aggressive multiagent cytotoxic combination plus dual HER2 targeting followed by anthracyclines.

It is ideal to have clinical-pathologic tests to distinguish those patients destined to achieve the surrogate endpoint of pCR from those who will not achieve it.

Despite linkage of TILs to improved outcome for triple-negative and HER2-enriched molecular subtypes (Lancet Oncol. 2018 Jan;19[1]:40-50), analysis of TILs is not standard practice in HER2-positive breast cancer in community settings. Optimal cutoffs are not well established, and TILs have not been linked to the choice of particular treatment options.

Currently, PET-CT scans are not part of National Comprehensive Cancer Network guidelines for pretreatment evaluation, except in patients for whom there is clinical suspicion of distant disease.

For those reasons, the main results of PREDIX-HER2 remain research tools that will focus our attention on the clinical-pathologic correlations Dr. Hatschek highlighted, but the results should have no influence on routine clinical practice at this time.

PREDIX-HER2 was funded by the Swedish Cancer Society, Radiumhemmet of Karolinska Institutet, Region Stockholm, and Roche Sweden. Dr. Hatschek disclosed relationships with Roche Sweden, Pfizer Sweden, and Pierre Fabre Sweden. Dr. Guarneri disclosed relationships with Roche, Novartis, and Eli Lilly.

Dr. Lyss was a community-based medical oncologist and clinical researcher for more than 35 years before his recent retirement. His clinical and research interests were focused on breast and lung cancers as well as expanding clinical trial access to medically underserved populations. He is based in St. Louis. He has no conflicts of interest.

SOURCE: Hatschek T et al. ESMO Breast Cancer 2020, Abstract 97O.

In an update of the PREDIX-HER2 trial, trastuzumab emtansine (T-DM1) remained equivalent to standard neoadjuvant chemotherapy plus dual-targeted HER2 therapy in producing pathologic complete remissions (pCRs) among patients with HER2-positive, metastatic breast cancer.

The new data also suggest tumor-infiltrating lymphocytes (TILs) and dramatic improvements in PET-CT scans can predict favorable outcomes in both treatment groups. Though these findings will be useful for research purposes, they likely won’t influence routine clinical practice.

Thomas Hatschek, MD, PhD, of Karolinska Institutet in Stockholm, presented the updated results from PREDIX-HER2 during the European Society for Medical Oncology: Breast Cancer virtual meeting.

PREDIX-HER2 included patients with HER2-positive breast cancer and tumor size greater than 20 mm or lymph node metastases.

Patients received neoadjuvant therapy (NAT) with docetaxel and trastuzumab plus pertuzumab (DTP) or T-DM1 every 3 weeks for a planned total of six courses. The protocol permitted switching to the competing treatment for progression, lack of response, or drug-related severe toxicity.

Postoperatively, all patients received triweekly epirubicin plus cyclophosphamide – four courses for the T-DM1 arm and two courses for the DTP arm. All patients then received triweekly adjuvant trastuzumab for 11 courses. The 62% of patients whose tumors were hormone receptor (HR)–positive received standard endocrine therapy postoperatively.
 

Updated results, predictors of pCR

At the 2019 ASCO annual meeting, PREDIX-HER2 investigators reported that, when compared with DTP, T-DM1 produced the same likelihood of pCR with less toxicity (ASCO 2019, Abstract 501). Updated data presented at ESMO Breast Cancer 2020 showed similar results.

The pCR rate was 45.5% in the DTP arm and 43.9% in the T-DM1 arm (P = .824). pCR rates were higher for HR-negative tumors – 63.6% in the DTP arm and 59% in the T-DM1 arm – than for HR-positive tumors – 36.4% in the DTP arm and 33.9% in the TDM-1 arm.

Three patients had disease progression with T-DM1, and none progressed with DTP. However, almost twice as many patients switched from DTP to T-DM1, compared with the other sequence.

Dr. Hatschek reported that the presence of at least 10% TILs predicted pCR in both treatment groups. Among patients who achieved a pCR, 52.2% had at least 10% TILs in baseline biopsies, and 30.4% had less than 10% TILs.

In addition, a decrease of FDG maximum standardized uptake value by more than 75% on protocol-required PET-CT scans was highly predictive of pCR. Among patients who achieved a pCR, 70.3% had a maximum standardized uptake value decrease of more than 75%, and 22.5% had a decrease of 75% or less.

At median follow-up of 28.5 months, event-free survival was similar between the treatment arms. Overall, there were 13 cases of progression, relapse, contralateral breast cancer, distant metastases, or death from any cause. There were five such events in the DTP arm and eight in the TDM-1 arm.

Dr. Hatschek concluded that neoadjuvant T-DM1 may be as effective as standard NAT in all clinical subgroups evaluated. Both TILs and PET-CT showed the potential to predict pCR and merit further study in the NAT setting.
 

An imperfect surrogate

By definition, a surrogate is “one appointed to act in place of another.” In the case of PREDIX-HER2 and most other NAT studies in HER2-positive breast cancer patients, pCR is a surrogate for the endpoint about which doctors and patients really care – cancer-free survival.

As such, pCR is not a perfect surrogate. Reproducibly, pCR has been highly predictive of disease-free survival and overall survival, especially in the HR-negative subset of HER2-positive patients.

However, despite improvements with dual targeting of HER2 in the TRYPHAENA trial (Eur J Cancer. 2018;89:27-35) and the use of T-DM1 for patients failing to achieve pCR in the immediately practice-changing KATHERINE trial (N Engl J Med. 2019;380:617-28), eventual relapse is seen in 10%-20% of patients in various clinical-pathologic subgroups.

In PREDIX-HER2, the pCR rate for node-positive patients was considerably lower with T-DM1 than with DTP (54.1% vs. 38%), noted Valentina Guarneri, MD, of the University of Padova (Italy), in her discussion of the trial at ESMO Breast Cancer 2020.

Patients with larger initial tumor size and multiple involved axillary nodes at diagnosis remain at increased risk of death because of cancer relapse.

Central nervous system relapse remains a vexing problem. Among patients with triple-positive breast cancer, relapses may occur late, despite pCR.

Patients whose tumors transform from HER2 positive to HER2 negative with NAT, seen in approximately 8% of cases in the KATHERINE trial (ESMO Breast Cancer 2020, Abstract 96O), may be another poor-risk group.
 

Clinical implications

PREDIX-HER2 is an important study. At the early time point of 2.4 years (especially early since most patients were HR-positive), if pCR is achieved, event-free survival is excellent with T-DM1 or an aggressive multiagent cytotoxic combination plus dual HER2 targeting followed by anthracyclines.

It is ideal to have clinical-pathologic tests to distinguish those patients destined to achieve the surrogate endpoint of pCR from those who will not achieve it.

Despite linkage of TILs to improved outcome for triple-negative and HER2-enriched molecular subtypes (Lancet Oncol. 2018 Jan;19[1]:40-50), analysis of TILs is not standard practice in HER2-positive breast cancer in community settings. Optimal cutoffs are not well established, and TILs have not been linked to the choice of particular treatment options.

Currently, PET-CT scans are not part of National Comprehensive Cancer Network guidelines for pretreatment evaluation, except in patients for whom there is clinical suspicion of distant disease.

For those reasons, the main results of PREDIX-HER2 remain research tools that will focus our attention on the clinical-pathologic correlations Dr. Hatschek highlighted, but the results should have no influence on routine clinical practice at this time.

PREDIX-HER2 was funded by the Swedish Cancer Society, Radiumhemmet of Karolinska Institutet, Region Stockholm, and Roche Sweden. Dr. Hatschek disclosed relationships with Roche Sweden, Pfizer Sweden, and Pierre Fabre Sweden. Dr. Guarneri disclosed relationships with Roche, Novartis, and Eli Lilly.

Dr. Lyss was a community-based medical oncologist and clinical researcher for more than 35 years before his recent retirement. His clinical and research interests were focused on breast and lung cancers as well as expanding clinical trial access to medically underserved populations. He is based in St. Louis. He has no conflicts of interest.

SOURCE: Hatschek T et al. ESMO Breast Cancer 2020, Abstract 97O.

In patients with newly diagnosed stage IV breast cancer and an intact primary tumor, locoregional therapy after optimal systemic therapy does not improve survival or quality of life, results of the phase 3 E2108 trial suggest.

Among 256 patients with stage IV breast cancer with intact primary tumors who had no disease progression for 4-8 months after the start of optimal systemic therapy, there were no significant differences in overall survival or progression-free survival between patients randomized to receive locoregional therapy and those who did not receive the locoregional treatment.

Although patients who did not receive locoregional treatment had a 150% higher rate of local recurrence/progression, health-related quality of life (HRQOL) was actually worse at 18 months among the patients who underwent locoregional therapy. There were no HRQOL differences at 6 months, 12 months, or 30 months of follow-up.

Seema A. Khan, MD, of Northwestern University, Chicago, reported these results during a plenary session broadcast as a part of the American Society of Clinical Oncology virtual scientific program.

“There is no hint here of an advantage in terms of survival with the use of early locoregional therapy for the primary site,” Dr. Khan said.

Although neither the E2108 trial nor similar trials showed an overall survival advantage for locoregional therapy, as many as 20% of patients who are treated with systemic therapy alone may need locoregional therapy with surgery and/or radiation at some point for palliation or progression, said invited discussant Julia R. White, MD, professor of radiation oncology at the Ohio State University, Columbus.

“Locoregional therapy should be reserved for these patients that become symptomatic or progress locally. There may be a role for routine locoregional therapy for de novo oligometastatic breast cancer in combination with systemic therapy plus ablative therapy” to secure long-term remission or cure, questions that are being addressed in ongoing clinical trials, Dr. White said.
 

Past data

An estimated 6% of newly diagnosed breast cancer patients present with stage IV disease and an intact primary tumor.

The rationale for locoregional therapy of the primary tumor in patients with metastatic disease is based on retrospective data suggesting a survival advantage. However, the studies were biased because of younger patient populations with small tumors, a higher proportion of estrogen receptor–positive disease, and a generally lower metastatic burden than that seen in the E2108 population, according to Dr. Khan.

She went on to cite two randomized trials with differing outcomes. One trial showed no survival advantage with locoregional therapy at 2 years (Lancet Oncol. 2015 Oct;16[13]:1380-8). The other showed an improvement in survival with locoregional therapy at 5 years (Ann Surg Oncol. 2018 Oct;25[11]:3141-9).
 

E2108 details

In the E2108 trial, patients first received optimal systemic therapy based on individual patient and disease features. Patients who had no disease progression or distant disease for at least 4-8 months of therapy were then randomized to additional therapy.

In one randomized arm, patients received continued systemic therapy alone. The other arm received early local therapy, which included complete tumor resection with free surgical margins and postoperative radiotherapy according to the standard of care.

A total of 390 patients were registered, and 256 went on to randomization. Of those subjects, 131 were randomized to the continued systemic therapy arm and 125 to the early local therapy arm. All patients in each arm were included in the efficacy analysis.

In all, 59.6% of randomized patients had hormone receptor–positive/HER2-negative disease, 8.2% had triple-negative disease, and 32.2% had HER2-positive disease. Metastases included bone-only disease in 37.9% of patients, visceral-only disease in 24.2%, and 40.9% in both sites.

Among the patients randomized to early local therapy, 14 did not have surgery for personal, clinical, or insurance reasons. Of the 109 who went on to surgery, 87 had clear surgical margins, and 74 received locoregional radiation therapy.
 

Survival, progression, and HRQOL

At a median follow-up of 53 months, the median overall survival was 54 months in each arm. There was no significant difference in survival between the study arms, with superimposable survival curves (hazard ratio, 1.09; P = .63).

An analysis of overall survival by tumor type showed that, for the 20 women with triple-negative disease, survival was worse with early local therapy (HR, 3.50). There were no differences in survival either for the 79 patients with HER2-positive disease or for the 137 patients with hormone receptor–positive/HER2-negative disease.

Locoregional progression occurred in 25.6% of patients assigned to continued systemic therapy, compared with 10.2% assigned to early local therapy. However, progression-free survival was virtually identical between the study arms (P = .40).

At most time points, there were no significant between-arm differences in HRQOL. The exception was at 18 months of follow-up, when the HRQOL was significantly lower among patients who had undergone early local therapy (P = .001).

“Based on available data, locoregional therapy for the primary tumor should not be offered to women with stage IV breast cancer with the expectation of a survival benefit. When systemic disease is well controlled with systemic therapy but the primary site is progressing, as does happen occasionally, locoregional treatment can be considered,” Dr. Khan concluded.

She noted there is an ongoing trial of similar design in Japan (JCOG-1017), with results expected in 2022.

The current trial was supported by the National Cancer Institute and Canadian Cancer Society. Dr. Khan reported no conflicts of interest. Dr. White reported institutional research funding from Intraop Medical.

SOURCE: Khan SA et al. ASCO 2020, Abstract LBA2.

In patients with newly diagnosed stage IV breast cancer and an intact primary tumor, locoregional therapy after optimal systemic therapy does not improve survival or quality of life, results of the phase 3 E2108 trial suggest.

Among 256 patients with stage IV breast cancer with intact primary tumors who had no disease progression for 4-8 months after the start of optimal systemic therapy, there were no significant differences in overall survival or progression-free survival between patients randomized to receive locoregional therapy and those who did not receive the locoregional treatment.

Although patients who did not receive locoregional treatment had a 150% higher rate of local recurrence/progression, health-related quality of life (HRQOL) was actually worse at 18 months among the patients who underwent locoregional therapy. There were no HRQOL differences at 6 months, 12 months, or 30 months of follow-up.

Seema A. Khan, MD, of Northwestern University, Chicago, reported these results during a plenary session broadcast as a part of the American Society of Clinical Oncology virtual scientific program.

“There is no hint here of an advantage in terms of survival with the use of early locoregional therapy for the primary site,” Dr. Khan said.

Although neither the E2108 trial nor similar trials showed an overall survival advantage for locoregional therapy, as many as 20% of patients who are treated with systemic therapy alone may need locoregional therapy with surgery and/or radiation at some point for palliation or progression, said invited discussant Julia R. White, MD, professor of radiation oncology at the Ohio State University, Columbus.

“Locoregional therapy should be reserved for these patients that become symptomatic or progress locally. There may be a role for routine locoregional therapy for de novo oligometastatic breast cancer in combination with systemic therapy plus ablative therapy” to secure long-term remission or cure, questions that are being addressed in ongoing clinical trials, Dr. White said.
 

Past data

An estimated 6% of newly diagnosed breast cancer patients present with stage IV disease and an intact primary tumor.

The rationale for locoregional therapy of the primary tumor in patients with metastatic disease is based on retrospective data suggesting a survival advantage. However, the studies were biased because of younger patient populations with small tumors, a higher proportion of estrogen receptor–positive disease, and a generally lower metastatic burden than that seen in the E2108 population, according to Dr. Khan.

She went on to cite two randomized trials with differing outcomes. One trial showed no survival advantage with locoregional therapy at 2 years (Lancet Oncol. 2015 Oct;16[13]:1380-8). The other showed an improvement in survival with locoregional therapy at 5 years (Ann Surg Oncol. 2018 Oct;25[11]:3141-9).
 

E2108 details

In the E2108 trial, patients first received optimal systemic therapy based on individual patient and disease features. Patients who had no disease progression or distant disease for at least 4-8 months of therapy were then randomized to additional therapy.

In one randomized arm, patients received continued systemic therapy alone. The other arm received early local therapy, which included complete tumor resection with free surgical margins and postoperative radiotherapy according to the standard of care.

A total of 390 patients were registered, and 256 went on to randomization. Of those subjects, 131 were randomized to the continued systemic therapy arm and 125 to the early local therapy arm. All patients in each arm were included in the efficacy analysis.

In all, 59.6% of randomized patients had hormone receptor–positive/HER2-negative disease, 8.2% had triple-negative disease, and 32.2% had HER2-positive disease. Metastases included bone-only disease in 37.9% of patients, visceral-only disease in 24.2%, and 40.9% in both sites.

Among the patients randomized to early local therapy, 14 did not have surgery for personal, clinical, or insurance reasons. Of the 109 who went on to surgery, 87 had clear surgical margins, and 74 received locoregional radiation therapy.
 

Survival, progression, and HRQOL

At a median follow-up of 53 months, the median overall survival was 54 months in each arm. There was no significant difference in survival between the study arms, with superimposable survival curves (hazard ratio, 1.09; P = .63).

An analysis of overall survival by tumor type showed that, for the 20 women with triple-negative disease, survival was worse with early local therapy (HR, 3.50). There were no differences in survival either for the 79 patients with HER2-positive disease or for the 137 patients with hormone receptor–positive/HER2-negative disease.

Locoregional progression occurred in 25.6% of patients assigned to continued systemic therapy, compared with 10.2% assigned to early local therapy. However, progression-free survival was virtually identical between the study arms (P = .40).

At most time points, there were no significant between-arm differences in HRQOL. The exception was at 18 months of follow-up, when the HRQOL was significantly lower among patients who had undergone early local therapy (P = .001).

“Based on available data, locoregional therapy for the primary tumor should not be offered to women with stage IV breast cancer with the expectation of a survival benefit. When systemic disease is well controlled with systemic therapy but the primary site is progressing, as does happen occasionally, locoregional treatment can be considered,” Dr. Khan concluded.

She noted there is an ongoing trial of similar design in Japan (JCOG-1017), with results expected in 2022.

The current trial was supported by the National Cancer Institute and Canadian Cancer Society. Dr. Khan reported no conflicts of interest. Dr. White reported institutional research funding from Intraop Medical.

SOURCE: Khan SA et al. ASCO 2020, Abstract LBA2.

In patients with newly diagnosed stage IV breast cancer and an intact primary tumor, locoregional therapy after optimal systemic therapy does not improve survival or quality of life, results of the phase 3 E2108 trial suggest.

Among 256 patients with stage IV breast cancer with intact primary tumors who had no disease progression for 4-8 months after the start of optimal systemic therapy, there were no significant differences in overall survival or progression-free survival between patients randomized to receive locoregional therapy and those who did not receive the locoregional treatment.

Although patients who did not receive locoregional treatment had a 150% higher rate of local recurrence/progression, health-related quality of life (HRQOL) was actually worse at 18 months among the patients who underwent locoregional therapy. There were no HRQOL differences at 6 months, 12 months, or 30 months of follow-up.

Seema A. Khan, MD, of Northwestern University, Chicago, reported these results during a plenary session broadcast as a part of the American Society of Clinical Oncology virtual scientific program.

“There is no hint here of an advantage in terms of survival with the use of early locoregional therapy for the primary site,” Dr. Khan said.

Although neither the E2108 trial nor similar trials showed an overall survival advantage for locoregional therapy, as many as 20% of patients who are treated with systemic therapy alone may need locoregional therapy with surgery and/or radiation at some point for palliation or progression, said invited discussant Julia R. White, MD, professor of radiation oncology at the Ohio State University, Columbus.

“Locoregional therapy should be reserved for these patients that become symptomatic or progress locally. There may be a role for routine locoregional therapy for de novo oligometastatic breast cancer in combination with systemic therapy plus ablative therapy” to secure long-term remission or cure, questions that are being addressed in ongoing clinical trials, Dr. White said.
 

Past data

An estimated 6% of newly diagnosed breast cancer patients present with stage IV disease and an intact primary tumor.

The rationale for locoregional therapy of the primary tumor in patients with metastatic disease is based on retrospective data suggesting a survival advantage. However, the studies were biased because of younger patient populations with small tumors, a higher proportion of estrogen receptor–positive disease, and a generally lower metastatic burden than that seen in the E2108 population, according to Dr. Khan.

She went on to cite two randomized trials with differing outcomes. One trial showed no survival advantage with locoregional therapy at 2 years (Lancet Oncol. 2015 Oct;16[13]:1380-8). The other showed an improvement in survival with locoregional therapy at 5 years (Ann Surg Oncol. 2018 Oct;25[11]:3141-9).
 

E2108 details

In the E2108 trial, patients first received optimal systemic therapy based on individual patient and disease features. Patients who had no disease progression or distant disease for at least 4-8 months of therapy were then randomized to additional therapy.

In one randomized arm, patients received continued systemic therapy alone. The other arm received early local therapy, which included complete tumor resection with free surgical margins and postoperative radiotherapy according to the standard of care.

A total of 390 patients were registered, and 256 went on to randomization. Of those subjects, 131 were randomized to the continued systemic therapy arm and 125 to the early local therapy arm. All patients in each arm were included in the efficacy analysis.

In all, 59.6% of randomized patients had hormone receptor–positive/HER2-negative disease, 8.2% had triple-negative disease, and 32.2% had HER2-positive disease. Metastases included bone-only disease in 37.9% of patients, visceral-only disease in 24.2%, and 40.9% in both sites.

Among the patients randomized to early local therapy, 14 did not have surgery for personal, clinical, or insurance reasons. Of the 109 who went on to surgery, 87 had clear surgical margins, and 74 received locoregional radiation therapy.
 

Survival, progression, and HRQOL

At a median follow-up of 53 months, the median overall survival was 54 months in each arm. There was no significant difference in survival between the study arms, with superimposable survival curves (hazard ratio, 1.09; P = .63).

An analysis of overall survival by tumor type showed that, for the 20 women with triple-negative disease, survival was worse with early local therapy (HR, 3.50). There were no differences in survival either for the 79 patients with HER2-positive disease or for the 137 patients with hormone receptor–positive/HER2-negative disease.

Locoregional progression occurred in 25.6% of patients assigned to continued systemic therapy, compared with 10.2% assigned to early local therapy. However, progression-free survival was virtually identical between the study arms (P = .40).

At most time points, there were no significant between-arm differences in HRQOL. The exception was at 18 months of follow-up, when the HRQOL was significantly lower among patients who had undergone early local therapy (P = .001).

“Based on available data, locoregional therapy for the primary tumor should not be offered to women with stage IV breast cancer with the expectation of a survival benefit. When systemic disease is well controlled with systemic therapy but the primary site is progressing, as does happen occasionally, locoregional treatment can be considered,” Dr. Khan concluded.

She noted there is an ongoing trial of similar design in Japan (JCOG-1017), with results expected in 2022.

The current trial was supported by the National Cancer Institute and Canadian Cancer Society. Dr. Khan reported no conflicts of interest. Dr. White reported institutional research funding from Intraop Medical.

SOURCE: Khan SA et al. ASCO 2020, Abstract LBA2.

The combination of pyrotinib and capecitabine significantly prolonged progression-free survival (PFS), when compared with lapatinib and capecitabine, among patients with previously treated HER2-positive metastatic breast cancer in a phase 3 trial.

PFS was extended by nearly 6 months among patients who received pyrotinib, a novel pan-HER2 inhibitor, combined with capecitabine. Grade 3 diarrhea occurred in nearly 31% of patients receiving the pyrotinib-capecitabine combination, though none of the patients discontinued treatment due to this adverse event.

Binghe Xu, MD, PhD, of the National Cancer Center/Cancer Hospital at the Chinese Academy of Medical Sciences and Peking Union Medical College in Beijing, presented these results, from the phase 3 PHOEBE trial, as part of the American Society of Clinical Oncology virtual scientific program.
 

The value of pyrotinib

Although there are already many targeted therapies for HER2-positive metastatic breast cancer, accessibility can be an issue, with drugs such as pertuzumab and trastuzumab emtansine (T-DM1) not available in all regions of the world, according to Dr. Xu.

“Before we initiated this clinical trial, lapatinib plus capecitabine was the only second-line standard of care against HER2-positive metastatic breast cancer in China,” he said.

Based, in part, on results of the PHOEBE trial, the combination of pyrotinib and capecitabine was approved in China as a second-line standard of care for patients with HER2-positive metastatic breast cancer, according to Dr. Xu.

Pyrotinib has now demonstrated “clinical value” in two phase 3 clinical trials, but its value in relation to pertuzumab, T-DM1, tucatinib, trastuzumab deruxtecan, or neratinib is less clear, said Aleix Prat, MD, PhD, of Hospital Clinic of Barcelona.

“Also, in my opinion, the toxicity profile needs attention,” Dr. Prat said in a discussion of the PHOEBE results that was also part of the virtual ASCO meeting.

The 31% incidence of grade 3 diarrhea was “very similar,” he said, to what was seen in PHENIX, another phase 3 trial of pyrotinib plus capecitabine that was presented at the 2019 ASCO annual meeting (J Clin Oncol 37, 2019 suppl; abstr 1001).

“What is the current therapy landscape? In my opinion, today, the first line remains taxane, trastuzumab, and pertuzumab; the second line T-DM1; and the third line tucatinib, trastuzumab, and capecitabine, with other treatment strategies reserved for later lines,” Dr. Prat said.

Study details

PHOEBE included 267 patients with HER2-positive metastatic breast cancer. They had previously received trastuzumab and taxanes, and/or anthracyclines, with up to two prior lines of chemotherapy for metastatic disease.

The patients’ median age was 50 years, 79% had visceral metastases at screening, and about 26% had trastuzumab resistance, Dr. Xu said. Resistance was defined as relapse within 6 months after adjuvant treatment or progression within 3 months of treatment for metastatic disease.

A statistically significant and clinically meaningful improvement was seen in PFS, the primary endpoint of the study, Dr. Xu said.

Median PFS by blinded independent central review was 12.5 months for the pyrotinib-capecitabine combination, compared with 6.8 months for lapatinib-capecitabine (hazard ratio, 0.39; 95% confidence interval, 0.27-0.56; P < .0001).

The PFS benefit was consistently observed across all predefined subgroups, including by trastuzumab resistance.

In trastuzumab-resistant patients, the median PFS was 12.5 months for the pyrotinib combination and 6.9 months for the lapatinib combination (HR, 0.60; 95% CI, 0.29-1.21). In patients without trastuzumab resistance, the median PFS was 12.5 months and 5.6 months, respectively (HR, 0.33; 95% CI, 0.21-0.51).

Although overall survival (OS) data were not yet mature, there was a “strong trend” toward a benefit with pyrotinib, Dr. Xu said. The 12-month OS rate was 91.3% for the pyrotinib combination and 77.4% for lapatinib. The median OS was not reached in either arm at the time of analysis.

Treatment-related adverse events of grade 3 or greater occurred in 57.5% of the pyrotinib arm and 34.1% of the lapatinib arm.

Diarrhea was the most common grade 3 or greater treatment-related adverse event, occurring in 30.6% of patients in the pyrotinib arm and 8.3% of those in the lapatinib arm. No grade 4 or 5 diarrhea was seen.

Overall, diarrhea occurred in 94.8% of patients in the pyrotinib arm and 62.1% of those in the lapatinib arm. However, pyrotinib-associated diarrhea was generally of low severity, occurred early, had a short duration, was reversible, and did not lead to treatment termination, according to Dr. Xu.

This study was funded by Jiangsu Hengrui Medicine Co. Ltd. Dr. Xu reported additional disclosures related to AstraZeneca, Eisai, Pfizer, and Roche. Dr. Prat disclosed relationships with Amgen, Daiichi Sankyo, Lilly, MSD Oncology, and other companies.

SOURCE: Xu B et al. ASCO 2020, Abstract 1003

The combination of pyrotinib and capecitabine significantly prolonged progression-free survival (PFS), when compared with lapatinib and capecitabine, among patients with previously treated HER2-positive metastatic breast cancer in a phase 3 trial.

PFS was extended by nearly 6 months among patients who received pyrotinib, a novel pan-HER2 inhibitor, combined with capecitabine. Grade 3 diarrhea occurred in nearly 31% of patients receiving the pyrotinib-capecitabine combination, though none of the patients discontinued treatment due to this adverse event.

Binghe Xu, MD, PhD, of the National Cancer Center/Cancer Hospital at the Chinese Academy of Medical Sciences and Peking Union Medical College in Beijing, presented these results, from the phase 3 PHOEBE trial, as part of the American Society of Clinical Oncology virtual scientific program.
 

The value of pyrotinib

Although there are already many targeted therapies for HER2-positive metastatic breast cancer, accessibility can be an issue, with drugs such as pertuzumab and trastuzumab emtansine (T-DM1) not available in all regions of the world, according to Dr. Xu.

“Before we initiated this clinical trial, lapatinib plus capecitabine was the only second-line standard of care against HER2-positive metastatic breast cancer in China,” he said.

Based, in part, on results of the PHOEBE trial, the combination of pyrotinib and capecitabine was approved in China as a second-line standard of care for patients with HER2-positive metastatic breast cancer, according to Dr. Xu.

Pyrotinib has now demonstrated “clinical value” in two phase 3 clinical trials, but its value in relation to pertuzumab, T-DM1, tucatinib, trastuzumab deruxtecan, or neratinib is less clear, said Aleix Prat, MD, PhD, of Hospital Clinic of Barcelona.

“Also, in my opinion, the toxicity profile needs attention,” Dr. Prat said in a discussion of the PHOEBE results that was also part of the virtual ASCO meeting.

The 31% incidence of grade 3 diarrhea was “very similar,” he said, to what was seen in PHENIX, another phase 3 trial of pyrotinib plus capecitabine that was presented at the 2019 ASCO annual meeting (J Clin Oncol 37, 2019 suppl; abstr 1001).

“What is the current therapy landscape? In my opinion, today, the first line remains taxane, trastuzumab, and pertuzumab; the second line T-DM1; and the third line tucatinib, trastuzumab, and capecitabine, with other treatment strategies reserved for later lines,” Dr. Prat said.

Study details

PHOEBE included 267 patients with HER2-positive metastatic breast cancer. They had previously received trastuzumab and taxanes, and/or anthracyclines, with up to two prior lines of chemotherapy for metastatic disease.

The patients’ median age was 50 years, 79% had visceral metastases at screening, and about 26% had trastuzumab resistance, Dr. Xu said. Resistance was defined as relapse within 6 months after adjuvant treatment or progression within 3 months of treatment for metastatic disease.

A statistically significant and clinically meaningful improvement was seen in PFS, the primary endpoint of the study, Dr. Xu said.

Median PFS by blinded independent central review was 12.5 months for the pyrotinib-capecitabine combination, compared with 6.8 months for lapatinib-capecitabine (hazard ratio, 0.39; 95% confidence interval, 0.27-0.56; P < .0001).

The PFS benefit was consistently observed across all predefined subgroups, including by trastuzumab resistance.

In trastuzumab-resistant patients, the median PFS was 12.5 months for the pyrotinib combination and 6.9 months for the lapatinib combination (HR, 0.60; 95% CI, 0.29-1.21). In patients without trastuzumab resistance, the median PFS was 12.5 months and 5.6 months, respectively (HR, 0.33; 95% CI, 0.21-0.51).

Although overall survival (OS) data were not yet mature, there was a “strong trend” toward a benefit with pyrotinib, Dr. Xu said. The 12-month OS rate was 91.3% for the pyrotinib combination and 77.4% for lapatinib. The median OS was not reached in either arm at the time of analysis.

Treatment-related adverse events of grade 3 or greater occurred in 57.5% of the pyrotinib arm and 34.1% of the lapatinib arm.

Diarrhea was the most common grade 3 or greater treatment-related adverse event, occurring in 30.6% of patients in the pyrotinib arm and 8.3% of those in the lapatinib arm. No grade 4 or 5 diarrhea was seen.

Overall, diarrhea occurred in 94.8% of patients in the pyrotinib arm and 62.1% of those in the lapatinib arm. However, pyrotinib-associated diarrhea was generally of low severity, occurred early, had a short duration, was reversible, and did not lead to treatment termination, according to Dr. Xu.

This study was funded by Jiangsu Hengrui Medicine Co. Ltd. Dr. Xu reported additional disclosures related to AstraZeneca, Eisai, Pfizer, and Roche. Dr. Prat disclosed relationships with Amgen, Daiichi Sankyo, Lilly, MSD Oncology, and other companies.

SOURCE: Xu B et al. ASCO 2020, Abstract 1003

The combination of pyrotinib and capecitabine significantly prolonged progression-free survival (PFS), when compared with lapatinib and capecitabine, among patients with previously treated HER2-positive metastatic breast cancer in a phase 3 trial.

PFS was extended by nearly 6 months among patients who received pyrotinib, a novel pan-HER2 inhibitor, combined with capecitabine. Grade 3 diarrhea occurred in nearly 31% of patients receiving the pyrotinib-capecitabine combination, though none of the patients discontinued treatment due to this adverse event.

Binghe Xu, MD, PhD, of the National Cancer Center/Cancer Hospital at the Chinese Academy of Medical Sciences and Peking Union Medical College in Beijing, presented these results, from the phase 3 PHOEBE trial, as part of the American Society of Clinical Oncology virtual scientific program.
 

The value of pyrotinib

Although there are already many targeted therapies for HER2-positive metastatic breast cancer, accessibility can be an issue, with drugs such as pertuzumab and trastuzumab emtansine (T-DM1) not available in all regions of the world, according to Dr. Xu.

“Before we initiated this clinical trial, lapatinib plus capecitabine was the only second-line standard of care against HER2-positive metastatic breast cancer in China,” he said.

Based, in part, on results of the PHOEBE trial, the combination of pyrotinib and capecitabine was approved in China as a second-line standard of care for patients with HER2-positive metastatic breast cancer, according to Dr. Xu.

Pyrotinib has now demonstrated “clinical value” in two phase 3 clinical trials, but its value in relation to pertuzumab, T-DM1, tucatinib, trastuzumab deruxtecan, or neratinib is less clear, said Aleix Prat, MD, PhD, of Hospital Clinic of Barcelona.

“Also, in my opinion, the toxicity profile needs attention,” Dr. Prat said in a discussion of the PHOEBE results that was also part of the virtual ASCO meeting.

The 31% incidence of grade 3 diarrhea was “very similar,” he said, to what was seen in PHENIX, another phase 3 trial of pyrotinib plus capecitabine that was presented at the 2019 ASCO annual meeting (J Clin Oncol 37, 2019 suppl; abstr 1001).

“What is the current therapy landscape? In my opinion, today, the first line remains taxane, trastuzumab, and pertuzumab; the second line T-DM1; and the third line tucatinib, trastuzumab, and capecitabine, with other treatment strategies reserved for later lines,” Dr. Prat said.

Study details

PHOEBE included 267 patients with HER2-positive metastatic breast cancer. They had previously received trastuzumab and taxanes, and/or anthracyclines, with up to two prior lines of chemotherapy for metastatic disease.

The patients’ median age was 50 years, 79% had visceral metastases at screening, and about 26% had trastuzumab resistance, Dr. Xu said. Resistance was defined as relapse within 6 months after adjuvant treatment or progression within 3 months of treatment for metastatic disease.

A statistically significant and clinically meaningful improvement was seen in PFS, the primary endpoint of the study, Dr. Xu said.

Median PFS by blinded independent central review was 12.5 months for the pyrotinib-capecitabine combination, compared with 6.8 months for lapatinib-capecitabine (hazard ratio, 0.39; 95% confidence interval, 0.27-0.56; P < .0001).

The PFS benefit was consistently observed across all predefined subgroups, including by trastuzumab resistance.

In trastuzumab-resistant patients, the median PFS was 12.5 months for the pyrotinib combination and 6.9 months for the lapatinib combination (HR, 0.60; 95% CI, 0.29-1.21). In patients without trastuzumab resistance, the median PFS was 12.5 months and 5.6 months, respectively (HR, 0.33; 95% CI, 0.21-0.51).

Although overall survival (OS) data were not yet mature, there was a “strong trend” toward a benefit with pyrotinib, Dr. Xu said. The 12-month OS rate was 91.3% for the pyrotinib combination and 77.4% for lapatinib. The median OS was not reached in either arm at the time of analysis.

Treatment-related adverse events of grade 3 or greater occurred in 57.5% of the pyrotinib arm and 34.1% of the lapatinib arm.

Diarrhea was the most common grade 3 or greater treatment-related adverse event, occurring in 30.6% of patients in the pyrotinib arm and 8.3% of those in the lapatinib arm. No grade 4 or 5 diarrhea was seen.

Overall, diarrhea occurred in 94.8% of patients in the pyrotinib arm and 62.1% of those in the lapatinib arm. However, pyrotinib-associated diarrhea was generally of low severity, occurred early, had a short duration, was reversible, and did not lead to treatment termination, according to Dr. Xu.

This study was funded by Jiangsu Hengrui Medicine Co. Ltd. Dr. Xu reported additional disclosures related to AstraZeneca, Eisai, Pfizer, and Roche. Dr. Prat disclosed relationships with Amgen, Daiichi Sankyo, Lilly, MSD Oncology, and other companies.

SOURCE: Xu B et al. ASCO 2020, Abstract 1003

For patients with BRCA-like triple-negative breast cancer (TNBC), adding veliparib to cisplatin chemotherapy may extend survival, based on results from the phase 3 SWOG S1416 trial.

All patients with BRCA-like TNBC had a significant improvement in progression-free survival (PFS) when they received veliparib plus cisplatin. Previously untreated patients with BRCA-like TNBC had a significant improvement in overall survival (OS) as well.

The results are a “very positive step towards expanding the role of PARP inhibitors beyond germline BRCA in breast cancer,” reported lead author Priyanka Sharma, MD, of the University of Kansas Medical Center in Kansas City, who presented the findings as part of the American Society of Clinical Oncology virtual scientific program.

According to Dr. Sharma, PARP inhibitors have demonstrated efficacy for certain patients with BRCA wild-type ovarian cancer, such as those with homologous recombination deficiency, which also occurs in approximately half of patients with BRCA wild-type TNBC. In TNBC, homologous recombination deficiency and other aberrations lead to a BRCA-like disease phenotype, which may respond to PARP inhibitors.

Dr. Sharma noted that previous attempts to use PARP inhibitors for BRCA wild-type TNBC have revealed obstacles, such as the inefficacy of PARP inhibitor monotherapy and dose-limiting myelosuppression when PARP inhibitors were added to chemotherapy. The issue of bone marrow toxicity may be mitigated by veliparib, which has minimal PARP-trapping activity, she explained.

“A phase 1 trial has demonstrated that adequate doses of cisplatin can be delivered safely in combination with the near-maximal single-agent dose of veliparib in patients with metastatic TNBC,” Dr. Sharma said.

She and her colleagues put this finding to the test in a phase 3 trial that enrolled 335 patients with metastatic and/or loco-regionally recurrent TNBC or BRCA-associated HER2-negative breast cancer. Patients could be previously untreated or have received one prior cytotoxic chemotherapy for metastatic disease.

Of the patients enrolled, 321 met eligibility criteria, 294 had germline BRCA testing, and 209 had BRCA-like assessment.

Patients were divided into the following groups: germline BRCA-associated disease (n = 37), BRCA-like disease (n = 99), non-BRCA-like disease (n = 110), and unclassified (n = 75).

In each group, patients were randomized in a 1:1 ratio to receive cisplatin (75 mg/m²on day 1) plus veliparib (300 mg twice daily on days 1-14) every 3 weeks, or cisplatin with placebo. The primary endpoint was PFS.

Results

Among patients with BRCA-like disease, there was a significant improvement in PFS and a trend toward improved OS when veliparib was added to cisplatin. The median PFS was 5.9 months with veliparib and 4.2 months with placebo (P = .006). The median OS was 14.0 months and 12.1 months, respectively (P = .067).

Among patients with previously untreated BRCA-like disease, there were significant improvements in both PFS and OS.

The median PFS in this group was 6.1 months with veliparib and 4.2 months with placebo (P = .008). The 12-month PFS rates were 23% and 3%, respectively.

The median OS in this group was 17.8 months with veliparib and 10.3 months with placebo (P = .048). The 24-month OS rates were 43% and 20%, respectively.

There were no survival benefits with veliparib among patients with unclassified disease, non-BRCA-like disease, or BRCA-associated disease.

Dr. Sharma noted that the lack of significant improvement in the BRCA-associated group was likely due to the small sample size. “FDA approval of PARP inhibitors for treatment of germline BRCA-associated metastatic breast cancer during the course of this trial impacted accrual to this group,” she said.

Veliparib was associated with a higher rate of grade 3-4 hematologic toxicities, including neutropenia (46% vs. 19%), leukopenia (27% vs. 7%), anemia (23% vs. 7%), and thrombocytopenia (19% vs. 3%).

Dr. Sharma said results from this trial should prompt further research. “The combination of veliparib plus cisplatin warrants further evaluation in larger randomized trials for patients with BRCA-like phenotype TNBC,” she said.

Invited discussant Catherine M. Kelly, MB BCh, of Mater Misericordiae University Hospital in Dublin, called the trial “an ambitious study” that has created a “valuable tissue bank” for future translational research. She agreed that more work is necessary.

“Further research is needed to identify the optimal homologous recombination deficiency biomarkers critical in the early treatment-naive and in the advanced treatment-exposed disease settings,” Dr. Kelly said.

SWOG S1416 was funded by the National Institutes of Health and AbbVie. Dr. Sharma disclosed relationships with AstraZeneca, Merck, Novartis, and other companies. Dr. Kelly reported affiliations with Pfizer, Novartis, Roche, and MSD Oncology.

SOURCE: Sharma et al. ASCO 2020, Abstract 1001.

For patients with BRCA-like triple-negative breast cancer (TNBC), adding veliparib to cisplatin chemotherapy may extend survival, based on results from the phase 3 SWOG S1416 trial.

All patients with BRCA-like TNBC had a significant improvement in progression-free survival (PFS) when they received veliparib plus cisplatin. Previously untreated patients with BRCA-like TNBC had a significant improvement in overall survival (OS) as well.

The results are a “very positive step towards expanding the role of PARP inhibitors beyond germline BRCA in breast cancer,” reported lead author Priyanka Sharma, MD, of the University of Kansas Medical Center in Kansas City, who presented the findings as part of the American Society of Clinical Oncology virtual scientific program.

According to Dr. Sharma, PARP inhibitors have demonstrated efficacy for certain patients with BRCA wild-type ovarian cancer, such as those with homologous recombination deficiency, which also occurs in approximately half of patients with BRCA wild-type TNBC. In TNBC, homologous recombination deficiency and other aberrations lead to a BRCA-like disease phenotype, which may respond to PARP inhibitors.

Dr. Sharma noted that previous attempts to use PARP inhibitors for BRCA wild-type TNBC have revealed obstacles, such as the inefficacy of PARP inhibitor monotherapy and dose-limiting myelosuppression when PARP inhibitors were added to chemotherapy. The issue of bone marrow toxicity may be mitigated by veliparib, which has minimal PARP-trapping activity, she explained.

“A phase 1 trial has demonstrated that adequate doses of cisplatin can be delivered safely in combination with the near-maximal single-agent dose of veliparib in patients with metastatic TNBC,” Dr. Sharma said.

She and her colleagues put this finding to the test in a phase 3 trial that enrolled 335 patients with metastatic and/or loco-regionally recurrent TNBC or BRCA-associated HER2-negative breast cancer. Patients could be previously untreated or have received one prior cytotoxic chemotherapy for metastatic disease.

Of the patients enrolled, 321 met eligibility criteria, 294 had germline BRCA testing, and 209 had BRCA-like assessment.

Patients were divided into the following groups: germline BRCA-associated disease (n = 37), BRCA-like disease (n = 99), non-BRCA-like disease (n = 110), and unclassified (n = 75).

In each group, patients were randomized in a 1:1 ratio to receive cisplatin (75 mg/m²on day 1) plus veliparib (300 mg twice daily on days 1-14) every 3 weeks, or cisplatin with placebo. The primary endpoint was PFS.

Results

Among patients with BRCA-like disease, there was a significant improvement in PFS and a trend toward improved OS when veliparib was added to cisplatin. The median PFS was 5.9 months with veliparib and 4.2 months with placebo (P = .006). The median OS was 14.0 months and 12.1 months, respectively (P = .067).

Among patients with previously untreated BRCA-like disease, there were significant improvements in both PFS and OS.

The median PFS in this group was 6.1 months with veliparib and 4.2 months with placebo (P = .008). The 12-month PFS rates were 23% and 3%, respectively.

The median OS in this group was 17.8 months with veliparib and 10.3 months with placebo (P = .048). The 24-month OS rates were 43% and 20%, respectively.

There were no survival benefits with veliparib among patients with unclassified disease, non-BRCA-like disease, or BRCA-associated disease.

Dr. Sharma noted that the lack of significant improvement in the BRCA-associated group was likely due to the small sample size. “FDA approval of PARP inhibitors for treatment of germline BRCA-associated metastatic breast cancer during the course of this trial impacted accrual to this group,” she said.

Veliparib was associated with a higher rate of grade 3-4 hematologic toxicities, including neutropenia (46% vs. 19%), leukopenia (27% vs. 7%), anemia (23% vs. 7%), and thrombocytopenia (19% vs. 3%).

Dr. Sharma said results from this trial should prompt further research. “The combination of veliparib plus cisplatin warrants further evaluation in larger randomized trials for patients with BRCA-like phenotype TNBC,” she said.

Invited discussant Catherine M. Kelly, MB BCh, of Mater Misericordiae University Hospital in Dublin, called the trial “an ambitious study” that has created a “valuable tissue bank” for future translational research. She agreed that more work is necessary.

“Further research is needed to identify the optimal homologous recombination deficiency biomarkers critical in the early treatment-naive and in the advanced treatment-exposed disease settings,” Dr. Kelly said.

SWOG S1416 was funded by the National Institutes of Health and AbbVie. Dr. Sharma disclosed relationships with AstraZeneca, Merck, Novartis, and other companies. Dr. Kelly reported affiliations with Pfizer, Novartis, Roche, and MSD Oncology.

SOURCE: Sharma et al. ASCO 2020, Abstract 1001.

For patients with BRCA-like triple-negative breast cancer (TNBC), adding veliparib to cisplatin chemotherapy may extend survival, based on results from the phase 3 SWOG S1416 trial.

All patients with BRCA-like TNBC had a significant improvement in progression-free survival (PFS) when they received veliparib plus cisplatin. Previously untreated patients with BRCA-like TNBC had a significant improvement in overall survival (OS) as well.

The results are a “very positive step towards expanding the role of PARP inhibitors beyond germline BRCA in breast cancer,” reported lead author Priyanka Sharma, MD, of the University of Kansas Medical Center in Kansas City, who presented the findings as part of the American Society of Clinical Oncology virtual scientific program.

According to Dr. Sharma, PARP inhibitors have demonstrated efficacy for certain patients with BRCA wild-type ovarian cancer, such as those with homologous recombination deficiency, which also occurs in approximately half of patients with BRCA wild-type TNBC. In TNBC, homologous recombination deficiency and other aberrations lead to a BRCA-like disease phenotype, which may respond to PARP inhibitors.

Dr. Sharma noted that previous attempts to use PARP inhibitors for BRCA wild-type TNBC have revealed obstacles, such as the inefficacy of PARP inhibitor monotherapy and dose-limiting myelosuppression when PARP inhibitors were added to chemotherapy. The issue of bone marrow toxicity may be mitigated by veliparib, which has minimal PARP-trapping activity, she explained.

“A phase 1 trial has demonstrated that adequate doses of cisplatin can be delivered safely in combination with the near-maximal single-agent dose of veliparib in patients with metastatic TNBC,” Dr. Sharma said.

She and her colleagues put this finding to the test in a phase 3 trial that enrolled 335 patients with metastatic and/or loco-regionally recurrent TNBC or BRCA-associated HER2-negative breast cancer. Patients could be previously untreated or have received one prior cytotoxic chemotherapy for metastatic disease.

Of the patients enrolled, 321 met eligibility criteria, 294 had germline BRCA testing, and 209 had BRCA-like assessment.

Patients were divided into the following groups: germline BRCA-associated disease (n = 37), BRCA-like disease (n = 99), non-BRCA-like disease (n = 110), and unclassified (n = 75).

In each group, patients were randomized in a 1:1 ratio to receive cisplatin (75 mg/m²on day 1) plus veliparib (300 mg twice daily on days 1-14) every 3 weeks, or cisplatin with placebo. The primary endpoint was PFS.

Results

Among patients with BRCA-like disease, there was a significant improvement in PFS and a trend toward improved OS when veliparib was added to cisplatin. The median PFS was 5.9 months with veliparib and 4.2 months with placebo (P = .006). The median OS was 14.0 months and 12.1 months, respectively (P = .067).

Among patients with previously untreated BRCA-like disease, there were significant improvements in both PFS and OS.

The median PFS in this group was 6.1 months with veliparib and 4.2 months with placebo (P = .008). The 12-month PFS rates were 23% and 3%, respectively.

The median OS in this group was 17.8 months with veliparib and 10.3 months with placebo (P = .048). The 24-month OS rates were 43% and 20%, respectively.

There were no survival benefits with veliparib among patients with unclassified disease, non-BRCA-like disease, or BRCA-associated disease.

Dr. Sharma noted that the lack of significant improvement in the BRCA-associated group was likely due to the small sample size. “FDA approval of PARP inhibitors for treatment of germline BRCA-associated metastatic breast cancer during the course of this trial impacted accrual to this group,” she said.

Veliparib was associated with a higher rate of grade 3-4 hematologic toxicities, including neutropenia (46% vs. 19%), leukopenia (27% vs. 7%), anemia (23% vs. 7%), and thrombocytopenia (19% vs. 3%).

Dr. Sharma said results from this trial should prompt further research. “The combination of veliparib plus cisplatin warrants further evaluation in larger randomized trials for patients with BRCA-like phenotype TNBC,” she said.

Invited discussant Catherine M. Kelly, MB BCh, of Mater Misericordiae University Hospital in Dublin, called the trial “an ambitious study” that has created a “valuable tissue bank” for future translational research. She agreed that more work is necessary.

“Further research is needed to identify the optimal homologous recombination deficiency biomarkers critical in the early treatment-naive and in the advanced treatment-exposed disease settings,” Dr. Kelly said.

SWOG S1416 was funded by the National Institutes of Health and AbbVie. Dr. Sharma disclosed relationships with AstraZeneca, Merck, Novartis, and other companies. Dr. Kelly reported affiliations with Pfizer, Novartis, Roche, and MSD Oncology.

SOURCE: Sharma et al. ASCO 2020, Abstract 1001.

In HER2-positive breast cancer patients with brain metastases treated with trastuzumab and capecitabine, add-on tucatinib increased median overall survival from 12 months to 18.1 months in a phase 2 trial.

The results were presented as part of the American Society of Clinical Oncology virtual scientific program and published simultaneously in the Journal of Clinical Oncology.

At 1 year, 70% of the 198 patients who had been randomized to tucatinib were alive versus 47% of the 93 patients randomized to placebo. Tucatinib reduced the risk of death by 42% (P = .005).

“This is the first double-blind, randomized trial of systemic therapy to our knowledge [that demonstrated] clinically meaningful gains in [overall survival] among patients with [brain metastases], including those with active metastases,” Nancy Lin, MD, associate chief of the division of breast oncology at Dana-Farber Cancer Institute in Boston and colleagues wrote in the Journal of Clinical Oncology.

The findings come from a substudy of the HER2CLIMB trial, which had similar outcomes but didn’t separate women with brain metastases from others. The study won tucatinib’s maker, Seattle Genetics, Food and Drug Administration approval for tucatinib in combination with trastuzumab and capecitabine for patients with unresectable or metastatic HER2-postive disease after failure of at least one treatment for advanced disease. In the United States, tucatinib costs over $18,000 a month, according to GoodRX and other sources.



The newly approved indication for tucatinib includes patients with brain metastases, but Dr. Lin and colleagues drove the point home by analyzing HER2CLIMB data solely in the 291 subjects who had baseline CNS lesions, which occur in up to half of women with advanced HER2-positive breast cancer.

Amy Tiersten, MD, a professor at Mount Sinai Hospital in New York, was not involved in the study but is convinced of the clinical benefit of tucatinib. Tucatinib “will be the standard of care for all patients with brain metastases ... regardless of” previous treatments, she said.

“It’s a total game changer. The addition of tucatinib made a large difference, including a hefty impact on overall survival. It will be interesting to see if this drug will be useful in earlier stages to help prevent brain metastases,” Dr. Tiersten said.

Among the large benefits she alluded to, the median CNS progression-free survival (PFS) – free of lesion progression or death – was 9.9 months with tucatinib versus 4.2 months with placebo (P < .00001).

At 1 year, 40% of tucatinib patients, but no patients in the placebo arm, were alive and free of CNS progression. Tucatinib reduced the risk of intracranial progression or death by 68%.

 

Active vs. stable brain metastasis

Among the 117 patients who entered the trial with stable, treated brain metastases – most by radiation, the rest by surgery – the median CNS PFS was 13.9 months with tucatinib versus 5.6 months with placebo (P = .002). In this group, the median overall survival was 15.7 months in the tucatinib arm and 13.6 month in the placebo arm (P = .70).

“Overall survival [in stable patients] numerically favored tucatinib to a small extent, but this did not reach statistical significance, albeit in a relatively small number of patients,” Dr. Lin said in her presentation.

Between-arm differences were significant in the 174 patients who entered the trial with active brain metastases, which refers to those that were either known but untreated, newly discovered on baseline MRI, or progressed after treatment. At 1 year, 35% of these patients in the tucatinib arm were still alive and free of CNS progression; however, there were no such patients in the placebo arm.

The median CNS PFS among patients with active brain metastases at study entrance was 9.5 months with tucatinib versus 4.1 months in the placebo arm (P < .0001). The median overall survival was 20.7 months and 11.6 months, respectively (P = .004).

Intracranial response was confirmed by MRI in 47% of tucatinib-treated patients with active brain metastasis at baseline versus 20% of patients on placebo (P = .03).
 

Re-treatment after progression

Thirty subjects – 21 on tucatinib and 9 on placebo – returned to their study arm after radiation for brain lesion progression.

The risk of second progression or death was reduced 67% when patients restarted tucatinib instead of placebo.

The median time from first CNS progression to a second progression or death was 7.6 months with tucatinib versus 3.1 months with placebo (P = .02).

“The data suggest a potential benefit for continuation of tucatinib beyond first isolated CNS progression,” Dr. Lin said.

As for why tucatinib helps, she and her colleagues speculated that, because tyrosine kinase inhibitors are small molecules, they can cross the blood brain barrier and effectively treat CNS lesions, while larger, antibody-based anti-HER2 agents, such as trastuzumab and pertuzumab, cannot.

Study entry required prior treatment with trastuzumab, pertuzumab, and ado-trastuzumab emtansine, as well as an Eastern Cooperative Oncology Group performance score of 0 or 1. More than 99% of the subjects in the analysis were women, and the median age was 52 years.

The treatment groups were well balanced. A bit over half of the subjects in both arms were in North America, and 57% were estrogen and/or progesterone receptor positive. Adverse events were reported previously.

This research was funded by tucatinib’s maker, Seattle Genetics. Dr. Lin and colleagues disclosed financial relationships with Seattle Genetics, including employment. Dr. Tiersten reported no relevant conflicts of interest.

[email protected]

SOURCE: Lin NU et al. ASCO 2020, Abstract 1005; J Clin Oncol. 2020 May 29. doi: 10.1200/JCO.20.00775

In HER2-positive breast cancer patients with brain metastases treated with trastuzumab and capecitabine, add-on tucatinib increased median overall survival from 12 months to 18.1 months in a phase 2 trial.

The results were presented as part of the American Society of Clinical Oncology virtual scientific program and published simultaneously in the Journal of Clinical Oncology.

At 1 year, 70% of the 198 patients who had been randomized to tucatinib were alive versus 47% of the 93 patients randomized to placebo. Tucatinib reduced the risk of death by 42% (P = .005).

“This is the first double-blind, randomized trial of systemic therapy to our knowledge [that demonstrated] clinically meaningful gains in [overall survival] among patients with [brain metastases], including those with active metastases,” Nancy Lin, MD, associate chief of the division of breast oncology at Dana-Farber Cancer Institute in Boston and colleagues wrote in the Journal of Clinical Oncology.

The findings come from a substudy of the HER2CLIMB trial, which had similar outcomes but didn’t separate women with brain metastases from others. The study won tucatinib’s maker, Seattle Genetics, Food and Drug Administration approval for tucatinib in combination with trastuzumab and capecitabine for patients with unresectable or metastatic HER2-postive disease after failure of at least one treatment for advanced disease. In the United States, tucatinib costs over $18,000 a month, according to GoodRX and other sources.



The newly approved indication for tucatinib includes patients with brain metastases, but Dr. Lin and colleagues drove the point home by analyzing HER2CLIMB data solely in the 291 subjects who had baseline CNS lesions, which occur in up to half of women with advanced HER2-positive breast cancer.

Amy Tiersten, MD, a professor at Mount Sinai Hospital in New York, was not involved in the study but is convinced of the clinical benefit of tucatinib. Tucatinib “will be the standard of care for all patients with brain metastases ... regardless of” previous treatments, she said.

“It’s a total game changer. The addition of tucatinib made a large difference, including a hefty impact on overall survival. It will be interesting to see if this drug will be useful in earlier stages to help prevent brain metastases,” Dr. Tiersten said.

Among the large benefits she alluded to, the median CNS progression-free survival (PFS) – free of lesion progression or death – was 9.9 months with tucatinib versus 4.2 months with placebo (P < .00001).

At 1 year, 40% of tucatinib patients, but no patients in the placebo arm, were alive and free of CNS progression. Tucatinib reduced the risk of intracranial progression or death by 68%.

 

Active vs. stable brain metastasis

Among the 117 patients who entered the trial with stable, treated brain metastases – most by radiation, the rest by surgery – the median CNS PFS was 13.9 months with tucatinib versus 5.6 months with placebo (P = .002). In this group, the median overall survival was 15.7 months in the tucatinib arm and 13.6 month in the placebo arm (P = .70).

“Overall survival [in stable patients] numerically favored tucatinib to a small extent, but this did not reach statistical significance, albeit in a relatively small number of patients,” Dr. Lin said in her presentation.

Between-arm differences were significant in the 174 patients who entered the trial with active brain metastases, which refers to those that were either known but untreated, newly discovered on baseline MRI, or progressed after treatment. At 1 year, 35% of these patients in the tucatinib arm were still alive and free of CNS progression; however, there were no such patients in the placebo arm.

The median CNS PFS among patients with active brain metastases at study entrance was 9.5 months with tucatinib versus 4.1 months in the placebo arm (P < .0001). The median overall survival was 20.7 months and 11.6 months, respectively (P = .004).

Intracranial response was confirmed by MRI in 47% of tucatinib-treated patients with active brain metastasis at baseline versus 20% of patients on placebo (P = .03).
 

Re-treatment after progression

Thirty subjects – 21 on tucatinib and 9 on placebo – returned to their study arm after radiation for brain lesion progression.

The risk of second progression or death was reduced 67% when patients restarted tucatinib instead of placebo.

The median time from first CNS progression to a second progression or death was 7.6 months with tucatinib versus 3.1 months with placebo (P = .02).

“The data suggest a potential benefit for continuation of tucatinib beyond first isolated CNS progression,” Dr. Lin said.

As for why tucatinib helps, she and her colleagues speculated that, because tyrosine kinase inhibitors are small molecules, they can cross the blood brain barrier and effectively treat CNS lesions, while larger, antibody-based anti-HER2 agents, such as trastuzumab and pertuzumab, cannot.

Study entry required prior treatment with trastuzumab, pertuzumab, and ado-trastuzumab emtansine, as well as an Eastern Cooperative Oncology Group performance score of 0 or 1. More than 99% of the subjects in the analysis were women, and the median age was 52 years.

The treatment groups were well balanced. A bit over half of the subjects in both arms were in North America, and 57% were estrogen and/or progesterone receptor positive. Adverse events were reported previously.

This research was funded by tucatinib’s maker, Seattle Genetics. Dr. Lin and colleagues disclosed financial relationships with Seattle Genetics, including employment. Dr. Tiersten reported no relevant conflicts of interest.

[email protected]

SOURCE: Lin NU et al. ASCO 2020, Abstract 1005; J Clin Oncol. 2020 May 29. doi: 10.1200/JCO.20.00775

In HER2-positive breast cancer patients with brain metastases treated with trastuzumab and capecitabine, add-on tucatinib increased median overall survival from 12 months to 18.1 months in a phase 2 trial.

The results were presented as part of the American Society of Clinical Oncology virtual scientific program and published simultaneously in the Journal of Clinical Oncology.

At 1 year, 70% of the 198 patients who had been randomized to tucatinib were alive versus 47% of the 93 patients randomized to placebo. Tucatinib reduced the risk of death by 42% (P = .005).

“This is the first double-blind, randomized trial of systemic therapy to our knowledge [that demonstrated] clinically meaningful gains in [overall survival] among patients with [brain metastases], including those with active metastases,” Nancy Lin, MD, associate chief of the division of breast oncology at Dana-Farber Cancer Institute in Boston and colleagues wrote in the Journal of Clinical Oncology.

The findings come from a substudy of the HER2CLIMB trial, which had similar outcomes but didn’t separate women with brain metastases from others. The study won tucatinib’s maker, Seattle Genetics, Food and Drug Administration approval for tucatinib in combination with trastuzumab and capecitabine for patients with unresectable or metastatic HER2-postive disease after failure of at least one treatment for advanced disease. In the United States, tucatinib costs over $18,000 a month, according to GoodRX and other sources.



The newly approved indication for tucatinib includes patients with brain metastases, but Dr. Lin and colleagues drove the point home by analyzing HER2CLIMB data solely in the 291 subjects who had baseline CNS lesions, which occur in up to half of women with advanced HER2-positive breast cancer.

Amy Tiersten, MD, a professor at Mount Sinai Hospital in New York, was not involved in the study but is convinced of the clinical benefit of tucatinib. Tucatinib “will be the standard of care for all patients with brain metastases ... regardless of” previous treatments, she said.

“It’s a total game changer. The addition of tucatinib made a large difference, including a hefty impact on overall survival. It will be interesting to see if this drug will be useful in earlier stages to help prevent brain metastases,” Dr. Tiersten said.

Among the large benefits she alluded to, the median CNS progression-free survival (PFS) – free of lesion progression or death – was 9.9 months with tucatinib versus 4.2 months with placebo (P < .00001).

At 1 year, 40% of tucatinib patients, but no patients in the placebo arm, were alive and free of CNS progression. Tucatinib reduced the risk of intracranial progression or death by 68%.

 

Active vs. stable brain metastasis

Among the 117 patients who entered the trial with stable, treated brain metastases – most by radiation, the rest by surgery – the median CNS PFS was 13.9 months with tucatinib versus 5.6 months with placebo (P = .002). In this group, the median overall survival was 15.7 months in the tucatinib arm and 13.6 month in the placebo arm (P = .70).

“Overall survival [in stable patients] numerically favored tucatinib to a small extent, but this did not reach statistical significance, albeit in a relatively small number of patients,” Dr. Lin said in her presentation.

Between-arm differences were significant in the 174 patients who entered the trial with active brain metastases, which refers to those that were either known but untreated, newly discovered on baseline MRI, or progressed after treatment. At 1 year, 35% of these patients in the tucatinib arm were still alive and free of CNS progression; however, there were no such patients in the placebo arm.

The median CNS PFS among patients with active brain metastases at study entrance was 9.5 months with tucatinib versus 4.1 months in the placebo arm (P < .0001). The median overall survival was 20.7 months and 11.6 months, respectively (P = .004).

Intracranial response was confirmed by MRI in 47% of tucatinib-treated patients with active brain metastasis at baseline versus 20% of patients on placebo (P = .03).
 

Re-treatment after progression

Thirty subjects – 21 on tucatinib and 9 on placebo – returned to their study arm after radiation for brain lesion progression.

The risk of second progression or death was reduced 67% when patients restarted tucatinib instead of placebo.

The median time from first CNS progression to a second progression or death was 7.6 months with tucatinib versus 3.1 months with placebo (P = .02).

“The data suggest a potential benefit for continuation of tucatinib beyond first isolated CNS progression,” Dr. Lin said.

As for why tucatinib helps, she and her colleagues speculated that, because tyrosine kinase inhibitors are small molecules, they can cross the blood brain barrier and effectively treat CNS lesions, while larger, antibody-based anti-HER2 agents, such as trastuzumab and pertuzumab, cannot.

Study entry required prior treatment with trastuzumab, pertuzumab, and ado-trastuzumab emtansine, as well as an Eastern Cooperative Oncology Group performance score of 0 or 1. More than 99% of the subjects in the analysis were women, and the median age was 52 years.

The treatment groups were well balanced. A bit over half of the subjects in both arms were in North America, and 57% were estrogen and/or progesterone receptor positive. Adverse events were reported previously.

This research was funded by tucatinib’s maker, Seattle Genetics. Dr. Lin and colleagues disclosed financial relationships with Seattle Genetics, including employment. Dr. Tiersten reported no relevant conflicts of interest.

[email protected]

SOURCE: Lin NU et al. ASCO 2020, Abstract 1005; J Clin Oncol. 2020 May 29. doi: 10.1200/JCO.20.00775

Adding pembrolizumab to standard chemotherapy significantly improved progression-free survival for patients with metastatic triple-negative breast cancer, but only if their tumors were enriched with comparatively high levels of the target programmed death ligand-1 (PD-L1), results of the KEYNOTE 355 trial showed.

Among 843 patients with triple-negative breast cancer (TNBC) randomized to receive either investigator’s choice of chemotherapy plus pembrolizumab (Keytruda) or placebo, patients whose tumors had a PD-L1 combined positive score (CPS) of 10 or higher had a median progression-free survival (PFS) of 9.7 months when treated with pembrolizumab and chemotherapy, compared with 5.6 months among patients treated with chemotherapy and placebo, reported Javier Cortes, MD, PhD, from the Vall d´Hebron Institute of Oncology in Madrid and Barcelona.

However, among patients with CPS between 1 and 10, there was no significant difference in PFS between the treatment arms, he said in a presentation made as a part of the 2020 American Society of Clinical Oncology virtual scientific program.

“The inclusion of taxanes and a known taxane/platinum–based regimen permits assessment of the clinical benefit of pembro in combination with several routinely used chemo partners. A trend toward improved efficacy with PD-L1 enrichment was observed in patients treated with pembro plus chemo. The improvement in progression-free survival with chemotherapy and pembrolizumab was observed across patient subgroups,” said Dr. Cortes.

In the KEYNOTE-522 study, adding pembrolizumab to chemotherapy in the neoadjuvant setting increased the likelihood that women with stage III or early node-positive TNBC would have a pathologic complete response and sustained clinical benefit.

KEYNOTE-355 examined whether pembrolizumab in combination with chemotherapy could provide additional benefit over chemotherapy alone in patients with previously untreated locally recurrent inoperable or metastatic TNBC.

Patients with previously untreated metastatic triple-negative breast cancer who had at least 6 months between definite surgery or last dose of adjuvant chemotherapy (whichever came last) and first disease recurrence were stratified by study chemotherapy received, tumor PD-L1 expression at baseline, and prior treatment with the same class of chemotherapy in the neoadjuvant and/or adjuvant setting.

The patients were then randomized in a 2:1 ratio to pembrolizumab plus chemotherapy based on the investigator’s choice of nab-paclitaxel, paclitaxel, or carboplatin-gemcitabine (562 patients) or to chemotherapy alone (281).

Pembrolizumab and placebo were administered in a double-blind fashion for up to 35 doses. Chemotherapy was given at the investigator’s discretion according to local guidelines. This trial was not powered or designed to compare differential efficacy of the various chemotherapy regimens, Dr. Cortes noted.

The trial had dual primary endpoints of PFS in patients with PD-L1–positive tumors (CPS > 10 and > 1) and in the intention-to-treat population, and overall survival both in PD-L1-positive patients and the ITT population. Overall survival results will be reported at a later date.

As noted before, the primary endpoint was met in the population of patients with CPS higher than 10, with median PFS of 9.7 among those receiving pembrolizumab versus 5.6 months among those receiving placebo, and an estimated 1 year PFS of 39.1% versus 23% for controls, translating into a hazard ratio for progression on pembrolizumab of 0.65 (P = .0012).

In the patients with CPS higher than 1, however, the median PFS was 7.6 months with pembrolizumab compared with 5.6 months with placebo, translating into a hazard ratio of 0.74. However, the results did not meet the prespecified boundary for significance. Because of this, the statistical significance in the ITT population was not tested.

“In patients with PD-L1 CPS 10 or higher tumors, the benefit of pembro/chemo on progression-free survival was generally consistent across most predefined subgroups, including eight geographic regions, ECOG performance status, on-study chemo, and prior treatment with the same class of chemo,” Dr. Cortes said.

Treatment-related adverse events occurred in 96.3% of the patients on pembrolizumab and 95% of patients on placebo. Grade 3 or greater adverse events occurred in 68.1% versus 66.9%, respectively. Two patients in the pembrolizumab arm died from a treatment-related event. There were no treatment-related deaths in the placebo arm.

The most common events were those typically associated with chemotherapy, including anemia, neutropenia, nausea, alopecia, fatigue, decreased neutrophil counts, and elevated liver transaminases. Immune-mediated adverse events of any grade occurred in 25.6% of patients in the pembrolizumab arm versus 6% of controls; none of these events were fatal.

“What is clear in this study is that again we’re seeing efficacy of pembrolizumab in combination with chemotherapy increases with increases in CPS,” according to the invited discussant Catherine M. Kelly, MB, BCh, from University College Dublin and Mater Misericordiae University Hospital in Dublin.

“The results from today’s KEYNOTE-355 appear consistent in terms of progression-free survival. However, it is ‘watch this space’ until we get overall survival data before we can make any further comparisons,” she added.

Questions that still need to be answered include which is the best test for measuring PD-L1, whether patients with CPS of 1 or more but less than 10 benefit from the treatment, which of the available chemotherapy regimens is the best partner for pembrolizumab, how to treat patients who don’t respond to the combination, and what are the implications for PD-1/PD-L1 inhibitors in late-stage disease if they are approved in the neoadjuvant or adjuvant setting, Dr. Kelly said.

The study was funded by Merck. Dr. Cortes disclosed honoraria from, a consulting/advisory role for, and institutional research funding from Merck and others. Dr. Kelly disclosed honoraria from MSD Oncology and others, and travel expenses from Pfizer and Roche.

SOURCE: Cortes J et al. ASCO 2020, Abstract 1000.

Adding pembrolizumab to standard chemotherapy significantly improved progression-free survival for patients with metastatic triple-negative breast cancer, but only if their tumors were enriched with comparatively high levels of the target programmed death ligand-1 (PD-L1), results of the KEYNOTE 355 trial showed.

Among 843 patients with triple-negative breast cancer (TNBC) randomized to receive either investigator’s choice of chemotherapy plus pembrolizumab (Keytruda) or placebo, patients whose tumors had a PD-L1 combined positive score (CPS) of 10 or higher had a median progression-free survival (PFS) of 9.7 months when treated with pembrolizumab and chemotherapy, compared with 5.6 months among patients treated with chemotherapy and placebo, reported Javier Cortes, MD, PhD, from the Vall d´Hebron Institute of Oncology in Madrid and Barcelona.

However, among patients with CPS between 1 and 10, there was no significant difference in PFS between the treatment arms, he said in a presentation made as a part of the 2020 American Society of Clinical Oncology virtual scientific program.

“The inclusion of taxanes and a known taxane/platinum–based regimen permits assessment of the clinical benefit of pembro in combination with several routinely used chemo partners. A trend toward improved efficacy with PD-L1 enrichment was observed in patients treated with pembro plus chemo. The improvement in progression-free survival with chemotherapy and pembrolizumab was observed across patient subgroups,” said Dr. Cortes.

In the KEYNOTE-522 study, adding pembrolizumab to chemotherapy in the neoadjuvant setting increased the likelihood that women with stage III or early node-positive TNBC would have a pathologic complete response and sustained clinical benefit.

KEYNOTE-355 examined whether pembrolizumab in combination with chemotherapy could provide additional benefit over chemotherapy alone in patients with previously untreated locally recurrent inoperable or metastatic TNBC.

Patients with previously untreated metastatic triple-negative breast cancer who had at least 6 months between definite surgery or last dose of adjuvant chemotherapy (whichever came last) and first disease recurrence were stratified by study chemotherapy received, tumor PD-L1 expression at baseline, and prior treatment with the same class of chemotherapy in the neoadjuvant and/or adjuvant setting.

The patients were then randomized in a 2:1 ratio to pembrolizumab plus chemotherapy based on the investigator’s choice of nab-paclitaxel, paclitaxel, or carboplatin-gemcitabine (562 patients) or to chemotherapy alone (281).

Pembrolizumab and placebo were administered in a double-blind fashion for up to 35 doses. Chemotherapy was given at the investigator’s discretion according to local guidelines. This trial was not powered or designed to compare differential efficacy of the various chemotherapy regimens, Dr. Cortes noted.

The trial had dual primary endpoints of PFS in patients with PD-L1–positive tumors (CPS > 10 and > 1) and in the intention-to-treat population, and overall survival both in PD-L1-positive patients and the ITT population. Overall survival results will be reported at a later date.

As noted before, the primary endpoint was met in the population of patients with CPS higher than 10, with median PFS of 9.7 among those receiving pembrolizumab versus 5.6 months among those receiving placebo, and an estimated 1 year PFS of 39.1% versus 23% for controls, translating into a hazard ratio for progression on pembrolizumab of 0.65 (P = .0012).

In the patients with CPS higher than 1, however, the median PFS was 7.6 months with pembrolizumab compared with 5.6 months with placebo, translating into a hazard ratio of 0.74. However, the results did not meet the prespecified boundary for significance. Because of this, the statistical significance in the ITT population was not tested.

“In patients with PD-L1 CPS 10 or higher tumors, the benefit of pembro/chemo on progression-free survival was generally consistent across most predefined subgroups, including eight geographic regions, ECOG performance status, on-study chemo, and prior treatment with the same class of chemo,” Dr. Cortes said.

Treatment-related adverse events occurred in 96.3% of the patients on pembrolizumab and 95% of patients on placebo. Grade 3 or greater adverse events occurred in 68.1% versus 66.9%, respectively. Two patients in the pembrolizumab arm died from a treatment-related event. There were no treatment-related deaths in the placebo arm.

The most common events were those typically associated with chemotherapy, including anemia, neutropenia, nausea, alopecia, fatigue, decreased neutrophil counts, and elevated liver transaminases. Immune-mediated adverse events of any grade occurred in 25.6% of patients in the pembrolizumab arm versus 6% of controls; none of these events were fatal.

“What is clear in this study is that again we’re seeing efficacy of pembrolizumab in combination with chemotherapy increases with increases in CPS,” according to the invited discussant Catherine M. Kelly, MB, BCh, from University College Dublin and Mater Misericordiae University Hospital in Dublin.

“The results from today’s KEYNOTE-355 appear consistent in terms of progression-free survival. However, it is ‘watch this space’ until we get overall survival data before we can make any further comparisons,” she added.

Questions that still need to be answered include which is the best test for measuring PD-L1, whether patients with CPS of 1 or more but less than 10 benefit from the treatment, which of the available chemotherapy regimens is the best partner for pembrolizumab, how to treat patients who don’t respond to the combination, and what are the implications for PD-1/PD-L1 inhibitors in late-stage disease if they are approved in the neoadjuvant or adjuvant setting, Dr. Kelly said.

The study was funded by Merck. Dr. Cortes disclosed honoraria from, a consulting/advisory role for, and institutional research funding from Merck and others. Dr. Kelly disclosed honoraria from MSD Oncology and others, and travel expenses from Pfizer and Roche.

SOURCE: Cortes J et al. ASCO 2020, Abstract 1000.

Adding pembrolizumab to standard chemotherapy significantly improved progression-free survival for patients with metastatic triple-negative breast cancer, but only if their tumors were enriched with comparatively high levels of the target programmed death ligand-1 (PD-L1), results of the KEYNOTE 355 trial showed.

Among 843 patients with triple-negative breast cancer (TNBC) randomized to receive either investigator’s choice of chemotherapy plus pembrolizumab (Keytruda) or placebo, patients whose tumors had a PD-L1 combined positive score (CPS) of 10 or higher had a median progression-free survival (PFS) of 9.7 months when treated with pembrolizumab and chemotherapy, compared with 5.6 months among patients treated with chemotherapy and placebo, reported Javier Cortes, MD, PhD, from the Vall d´Hebron Institute of Oncology in Madrid and Barcelona.

However, among patients with CPS between 1 and 10, there was no significant difference in PFS between the treatment arms, he said in a presentation made as a part of the 2020 American Society of Clinical Oncology virtual scientific program.

“The inclusion of taxanes and a known taxane/platinum–based regimen permits assessment of the clinical benefit of pembro in combination with several routinely used chemo partners. A trend toward improved efficacy with PD-L1 enrichment was observed in patients treated with pembro plus chemo. The improvement in progression-free survival with chemotherapy and pembrolizumab was observed across patient subgroups,” said Dr. Cortes.

In the KEYNOTE-522 study, adding pembrolizumab to chemotherapy in the neoadjuvant setting increased the likelihood that women with stage III or early node-positive TNBC would have a pathologic complete response and sustained clinical benefit.

KEYNOTE-355 examined whether pembrolizumab in combination with chemotherapy could provide additional benefit over chemotherapy alone in patients with previously untreated locally recurrent inoperable or metastatic TNBC.

Patients with previously untreated metastatic triple-negative breast cancer who had at least 6 months between definite surgery or last dose of adjuvant chemotherapy (whichever came last) and first disease recurrence were stratified by study chemotherapy received, tumor PD-L1 expression at baseline, and prior treatment with the same class of chemotherapy in the neoadjuvant and/or adjuvant setting.

The patients were then randomized in a 2:1 ratio to pembrolizumab plus chemotherapy based on the investigator’s choice of nab-paclitaxel, paclitaxel, or carboplatin-gemcitabine (562 patients) or to chemotherapy alone (281).

Pembrolizumab and placebo were administered in a double-blind fashion for up to 35 doses. Chemotherapy was given at the investigator’s discretion according to local guidelines. This trial was not powered or designed to compare differential efficacy of the various chemotherapy regimens, Dr. Cortes noted.

The trial had dual primary endpoints of PFS in patients with PD-L1–positive tumors (CPS > 10 and > 1) and in the intention-to-treat population, and overall survival both in PD-L1-positive patients and the ITT population. Overall survival results will be reported at a later date.

As noted before, the primary endpoint was met in the population of patients with CPS higher than 10, with median PFS of 9.7 among those receiving pembrolizumab versus 5.6 months among those receiving placebo, and an estimated 1 year PFS of 39.1% versus 23% for controls, translating into a hazard ratio for progression on pembrolizumab of 0.65 (P = .0012).

In the patients with CPS higher than 1, however, the median PFS was 7.6 months with pembrolizumab compared with 5.6 months with placebo, translating into a hazard ratio of 0.74. However, the results did not meet the prespecified boundary for significance. Because of this, the statistical significance in the ITT population was not tested.

“In patients with PD-L1 CPS 10 or higher tumors, the benefit of pembro/chemo on progression-free survival was generally consistent across most predefined subgroups, including eight geographic regions, ECOG performance status, on-study chemo, and prior treatment with the same class of chemo,” Dr. Cortes said.

Treatment-related adverse events occurred in 96.3% of the patients on pembrolizumab and 95% of patients on placebo. Grade 3 or greater adverse events occurred in 68.1% versus 66.9%, respectively. Two patients in the pembrolizumab arm died from a treatment-related event. There were no treatment-related deaths in the placebo arm.

The most common events were those typically associated with chemotherapy, including anemia, neutropenia, nausea, alopecia, fatigue, decreased neutrophil counts, and elevated liver transaminases. Immune-mediated adverse events of any grade occurred in 25.6% of patients in the pembrolizumab arm versus 6% of controls; none of these events were fatal.

“What is clear in this study is that again we’re seeing efficacy of pembrolizumab in combination with chemotherapy increases with increases in CPS,” according to the invited discussant Catherine M. Kelly, MB, BCh, from University College Dublin and Mater Misericordiae University Hospital in Dublin.

“The results from today’s KEYNOTE-355 appear consistent in terms of progression-free survival. However, it is ‘watch this space’ until we get overall survival data before we can make any further comparisons,” she added.

Questions that still need to be answered include which is the best test for measuring PD-L1, whether patients with CPS of 1 or more but less than 10 benefit from the treatment, which of the available chemotherapy regimens is the best partner for pembrolizumab, how to treat patients who don’t respond to the combination, and what are the implications for PD-1/PD-L1 inhibitors in late-stage disease if they are approved in the neoadjuvant or adjuvant setting, Dr. Kelly said.

The study was funded by Merck. Dr. Cortes disclosed honoraria from, a consulting/advisory role for, and institutional research funding from Merck and others. Dr. Kelly disclosed honoraria from MSD Oncology and others, and travel expenses from Pfizer and Roche.

SOURCE: Cortes J et al. ASCO 2020, Abstract 1000.

Adding the AKT inhibitor ipatasertib to paclitaxel may provide an overall survival (OS) benefit for inoperable locally advanced/metastatic triple-negative breast cancer (TNBC), according to final results of the phase 2 LOTUS trial.

The median OS was 25.8 months in patients who received ipatasertib plus paclitaxel and 16.9 months in patients who received paclitaxel plus placebo. Although this difference was not statistically significant, it was “clinically meaningful,” according to Rebecca Dent, MD, of the National Cancer Center Singapore. Dr. Dent presented OS data from the LOTUS trial at the European Society of Medical Oncology: Breast Cancer virtual meeting.

Previously reported data showed a progression-free survival benefit in the ipatasertib arm, compared with the placebo arm – 6.2 months and 4.9 months, respectively (Lancet Oncol. 2017 Oct;18[10]:1360-72). An enhanced effect was noted in patients with PIK3CA/AKT1/PTEN–altered tumors, but the OS data were not mature at the time of that primary analysis.
 

Patients, treatment, and safety

LOTUS participants had measurable locally advanced/metastatic TNBC that was previously untreated with systemic therapy, and they were stratified by prior adjuvant therapy, chemotherapy-free interval, and tumor immunohistochemistry PTEN status.

Patients were randomized 1:1 to receive paclitaxel at a dose of 80 mg/m² on days 1, 8, and 15 of each 28-day cycle plus either placebo (n = 62) or ipatasertib at a dose of 400 mg on days 1-21 (n = 62).

The safety results didn’t differ between the primary and updated results, Dr. Dent noted.

“What we can say is that the combination is extremely well tolerated, especially when we compare it to other targeted agents targeting this pathway,” she said. “What we do see is noticeable diarrhea ... [and] an increase in sensory neuropathy, which is not entirely unexpected.”

Subsequent systemic anticancer therapy was required in 77% of patients in the ipatasertib arm and 90% of patients in the placebo arm.
 

OS results

The final OS data show a numerical advantage for patients in the ipatasertib arm compared with the placebo arm. The 1-year OS was 83% in the ipatasertib arm and 68% in the placebo arm. The median OS was 25.8 months and 16.9 months, respectively (stratified hazard ratio, 0.80).

“This is a clinically meaningful improvement of 9 months in overall survival, which is indeed not too dissimilar to what we have seen in patients with PD-L1-positive TNBC who are receiving immune checkpoint inhibition in combination with chemotherapy,” Dr. Dent said.

However, the 95% confidence interval for the stratified OS hazard ratio crossed 1 (0.50-1.28). Therefore, the findings require confirmatory phase 3 trial results, Dr. Dent said.

The OS improvements with ipatasertib were seen “in all biomarker-defined subgroups – PTEN normal or low, PIK3CA/AKT1/PTEN altered or non-altered,” she said. OS benefits were more pronounced in patients with altered PIK3C/AKT1/PTEN status, but the numbers are too small to make definitive conclusions, according to Dr. Dent.
 

‘Promising’ results, confirmation needed

Invited discussant Suzette Delaloge, MD, head of the breast cancer department at Gustave Roussy, Paris, said the OS findings from LOTUS are “quite promising,” and the safety data are “reassuring.”

The findings are comparable to those of the recently published PAKT trial (J Clin Oncol. 2020 Feb 10;38[5]:423-33), she said, noting that “AKT inhibition in combination with paclitaxel deserves phase 3 development, and this is ongoing in major phase 3 trials.”

Dr. Delaloge also noted that the efficacy may not be limited to PIK3CA/AKT–altered tumors, and given the heterogeneity of TNBC – which may explain the differences seen among various studies – “it is very important that such phase 3 trials ideally involve extensive genomical definitions of tumors so that we understand what it is we are talking about and what is the real effect of the drug.”

“The adequate positioning of AKT inhibition in competition/complementation with other ongoing strategies remains to be defined,” she said. “I think these drugs are ready for translation to early phases.”

Dr. Dent said the results of LOTUS warrant confirmation in the ongoing, randomized phase 3 IPATunity130 trial , in which researchers are evaluating first-line ipatasertib plus paclitaxel for metastatic TNBC. She noted that the small sample sizes and heterogeneity of TNBC among LOTUS participants limited the interpretation of the findings.

In another trial, IPATunity170, researchers are evaluating the first-line role of ipatasertib plus paclitaxel and atezolizumab in locally advanced or metastatic TNBC.

“This is an exciting triplet combination that’s been evaluated already in the phase 1 setting, and now we have a phase 3 study evaluating the triplet,” Dr. Dent said.

The LOTUS trial was funded by Roche/Genentech. Dr. Dent reported receiving honoraria from Roche, Novartis, Lilly, Pfizer, Eisai, Merck, and AstraZeneca. Dr. Delaloge reported personal financial interests in AstraZeneca until 2018 and travel and accommodation support from AstraZeneca, Pfizer, Roche, and Pierre Fabre.

[email protected]

SOURCE: Dent R et al. ESMO Breast Cancer 2020, Abstract 139O

Adding the AKT inhibitor ipatasertib to paclitaxel may provide an overall survival (OS) benefit for inoperable locally advanced/metastatic triple-negative breast cancer (TNBC), according to final results of the phase 2 LOTUS trial.

The median OS was 25.8 months in patients who received ipatasertib plus paclitaxel and 16.9 months in patients who received paclitaxel plus placebo. Although this difference was not statistically significant, it was “clinically meaningful,” according to Rebecca Dent, MD, of the National Cancer Center Singapore. Dr. Dent presented OS data from the LOTUS trial at the European Society of Medical Oncology: Breast Cancer virtual meeting.

Previously reported data showed a progression-free survival benefit in the ipatasertib arm, compared with the placebo arm – 6.2 months and 4.9 months, respectively (Lancet Oncol. 2017 Oct;18[10]:1360-72). An enhanced effect was noted in patients with PIK3CA/AKT1/PTEN–altered tumors, but the OS data were not mature at the time of that primary analysis.
 

Patients, treatment, and safety

LOTUS participants had measurable locally advanced/metastatic TNBC that was previously untreated with systemic therapy, and they were stratified by prior adjuvant therapy, chemotherapy-free interval, and tumor immunohistochemistry PTEN status.

Patients were randomized 1:1 to receive paclitaxel at a dose of 80 mg/m² on days 1, 8, and 15 of each 28-day cycle plus either placebo (n = 62) or ipatasertib at a dose of 400 mg on days 1-21 (n = 62).

The safety results didn’t differ between the primary and updated results, Dr. Dent noted.

“What we can say is that the combination is extremely well tolerated, especially when we compare it to other targeted agents targeting this pathway,” she said. “What we do see is noticeable diarrhea ... [and] an increase in sensory neuropathy, which is not entirely unexpected.”

Subsequent systemic anticancer therapy was required in 77% of patients in the ipatasertib arm and 90% of patients in the placebo arm.
 

OS results

The final OS data show a numerical advantage for patients in the ipatasertib arm compared with the placebo arm. The 1-year OS was 83% in the ipatasertib arm and 68% in the placebo arm. The median OS was 25.8 months and 16.9 months, respectively (stratified hazard ratio, 0.80).

“This is a clinically meaningful improvement of 9 months in overall survival, which is indeed not too dissimilar to what we have seen in patients with PD-L1-positive TNBC who are receiving immune checkpoint inhibition in combination with chemotherapy,” Dr. Dent said.

However, the 95% confidence interval for the stratified OS hazard ratio crossed 1 (0.50-1.28). Therefore, the findings require confirmatory phase 3 trial results, Dr. Dent said.

The OS improvements with ipatasertib were seen “in all biomarker-defined subgroups – PTEN normal or low, PIK3CA/AKT1/PTEN altered or non-altered,” she said. OS benefits were more pronounced in patients with altered PIK3C/AKT1/PTEN status, but the numbers are too small to make definitive conclusions, according to Dr. Dent.
 

‘Promising’ results, confirmation needed

Invited discussant Suzette Delaloge, MD, head of the breast cancer department at Gustave Roussy, Paris, said the OS findings from LOTUS are “quite promising,” and the safety data are “reassuring.”

The findings are comparable to those of the recently published PAKT trial (J Clin Oncol. 2020 Feb 10;38[5]:423-33), she said, noting that “AKT inhibition in combination with paclitaxel deserves phase 3 development, and this is ongoing in major phase 3 trials.”

Dr. Delaloge also noted that the efficacy may not be limited to PIK3CA/AKT–altered tumors, and given the heterogeneity of TNBC – which may explain the differences seen among various studies – “it is very important that such phase 3 trials ideally involve extensive genomical definitions of tumors so that we understand what it is we are talking about and what is the real effect of the drug.”

“The adequate positioning of AKT inhibition in competition/complementation with other ongoing strategies remains to be defined,” she said. “I think these drugs are ready for translation to early phases.”

Dr. Dent said the results of LOTUS warrant confirmation in the ongoing, randomized phase 3 IPATunity130 trial , in which researchers are evaluating first-line ipatasertib plus paclitaxel for metastatic TNBC. She noted that the small sample sizes and heterogeneity of TNBC among LOTUS participants limited the interpretation of the findings.

In another trial, IPATunity170, researchers are evaluating the first-line role of ipatasertib plus paclitaxel and atezolizumab in locally advanced or metastatic TNBC.

“This is an exciting triplet combination that’s been evaluated already in the phase 1 setting, and now we have a phase 3 study evaluating the triplet,” Dr. Dent said.

The LOTUS trial was funded by Roche/Genentech. Dr. Dent reported receiving honoraria from Roche, Novartis, Lilly, Pfizer, Eisai, Merck, and AstraZeneca. Dr. Delaloge reported personal financial interests in AstraZeneca until 2018 and travel and accommodation support from AstraZeneca, Pfizer, Roche, and Pierre Fabre.

[email protected]

SOURCE: Dent R et al. ESMO Breast Cancer 2020, Abstract 139O

Adding the AKT inhibitor ipatasertib to paclitaxel may provide an overall survival (OS) benefit for inoperable locally advanced/metastatic triple-negative breast cancer (TNBC), according to final results of the phase 2 LOTUS trial.

The median OS was 25.8 months in patients who received ipatasertib plus paclitaxel and 16.9 months in patients who received paclitaxel plus placebo. Although this difference was not statistically significant, it was “clinically meaningful,” according to Rebecca Dent, MD, of the National Cancer Center Singapore. Dr. Dent presented OS data from the LOTUS trial at the European Society of Medical Oncology: Breast Cancer virtual meeting.

Previously reported data showed a progression-free survival benefit in the ipatasertib arm, compared with the placebo arm – 6.2 months and 4.9 months, respectively (Lancet Oncol. 2017 Oct;18[10]:1360-72). An enhanced effect was noted in patients with PIK3CA/AKT1/PTEN–altered tumors, but the OS data were not mature at the time of that primary analysis.
 

Patients, treatment, and safety

LOTUS participants had measurable locally advanced/metastatic TNBC that was previously untreated with systemic therapy, and they were stratified by prior adjuvant therapy, chemotherapy-free interval, and tumor immunohistochemistry PTEN status.

Patients were randomized 1:1 to receive paclitaxel at a dose of 80 mg/m² on days 1, 8, and 15 of each 28-day cycle plus either placebo (n = 62) or ipatasertib at a dose of 400 mg on days 1-21 (n = 62).

The safety results didn’t differ between the primary and updated results, Dr. Dent noted.

“What we can say is that the combination is extremely well tolerated, especially when we compare it to other targeted agents targeting this pathway,” she said. “What we do see is noticeable diarrhea ... [and] an increase in sensory neuropathy, which is not entirely unexpected.”

Subsequent systemic anticancer therapy was required in 77% of patients in the ipatasertib arm and 90% of patients in the placebo arm.
 

OS results

The final OS data show a numerical advantage for patients in the ipatasertib arm compared with the placebo arm. The 1-year OS was 83% in the ipatasertib arm and 68% in the placebo arm. The median OS was 25.8 months and 16.9 months, respectively (stratified hazard ratio, 0.80).

“This is a clinically meaningful improvement of 9 months in overall survival, which is indeed not too dissimilar to what we have seen in patients with PD-L1-positive TNBC who are receiving immune checkpoint inhibition in combination with chemotherapy,” Dr. Dent said.

However, the 95% confidence interval for the stratified OS hazard ratio crossed 1 (0.50-1.28). Therefore, the findings require confirmatory phase 3 trial results, Dr. Dent said.

The OS improvements with ipatasertib were seen “in all biomarker-defined subgroups – PTEN normal or low, PIK3CA/AKT1/PTEN altered or non-altered,” she said. OS benefits were more pronounced in patients with altered PIK3C/AKT1/PTEN status, but the numbers are too small to make definitive conclusions, according to Dr. Dent.
 

‘Promising’ results, confirmation needed

Invited discussant Suzette Delaloge, MD, head of the breast cancer department at Gustave Roussy, Paris, said the OS findings from LOTUS are “quite promising,” and the safety data are “reassuring.”

The findings are comparable to those of the recently published PAKT trial (J Clin Oncol. 2020 Feb 10;38[5]:423-33), she said, noting that “AKT inhibition in combination with paclitaxel deserves phase 3 development, and this is ongoing in major phase 3 trials.”

Dr. Delaloge also noted that the efficacy may not be limited to PIK3CA/AKT–altered tumors, and given the heterogeneity of TNBC – which may explain the differences seen among various studies – “it is very important that such phase 3 trials ideally involve extensive genomical definitions of tumors so that we understand what it is we are talking about and what is the real effect of the drug.”

“The adequate positioning of AKT inhibition in competition/complementation with other ongoing strategies remains to be defined,” she said. “I think these drugs are ready for translation to early phases.”

Dr. Dent said the results of LOTUS warrant confirmation in the ongoing, randomized phase 3 IPATunity130 trial , in which researchers are evaluating first-line ipatasertib plus paclitaxel for metastatic TNBC. She noted that the small sample sizes and heterogeneity of TNBC among LOTUS participants limited the interpretation of the findings.

In another trial, IPATunity170, researchers are evaluating the first-line role of ipatasertib plus paclitaxel and atezolizumab in locally advanced or metastatic TNBC.

“This is an exciting triplet combination that’s been evaluated already in the phase 1 setting, and now we have a phase 3 study evaluating the triplet,” Dr. Dent said.

The LOTUS trial was funded by Roche/Genentech. Dr. Dent reported receiving honoraria from Roche, Novartis, Lilly, Pfizer, Eisai, Merck, and AstraZeneca. Dr. Delaloge reported personal financial interests in AstraZeneca until 2018 and travel and accommodation support from AstraZeneca, Pfizer, Roche, and Pierre Fabre.

[email protected]

SOURCE: Dent R et al. ESMO Breast Cancer 2020, Abstract 139O

New data from a large Swedish study show that mammography screening for breast cancer reduces the rate of both advanced and fatal breast cancer.

Three experts who were approached by Medscape Medical News say this is further evidence that regular screening mammography significantly reduces the risk of dying from breast cancer, but one expert questioned the methodology used in the study.

The primary goal of cancer screening is to detect tumors at an early stage, when they are most treatable. The hope is that this will reduce the number of advanced cancers associated with poor prognosis and hence the risk of dying from that cancer.

So far, for mammography, the data have been somewhat conflicting. For example, some evidence suggests that widespread breast cancer screening may catch more small, slow-growing tumors that are unlikely to be fatal but will not curb the number of cancers that are diagnosed at a late stage.

The new study, published online in Cancer, refutes this view.

It followed a Swedish cohort of 549,091 women (covering approximately 30% of the Swedish screening-eligible population) who underwent regular mammography.

For the women in this cohort, there was a statistically significant 41% reduction in the risk of dying of breast cancer within 10 years and a 25% reduction in the incidence of advanced disease, compared to women who did not undergo screening. “Even in this age of effective treatments, early detection confers a substantial and significant additional reduction in risk of dying from breast cancer,” said lead author Stephen W. Duffy, MSc, from the Center for Cancer Prevention at Queen Mary University, London, United Kingdom.

The current study confirms the findings of a smaller earlier study (Cancer. 2019;125:515-23) from the same investigators. “It finds the same result with an extremely large evidence base, with more than half a million women, and it also adds further to the evidence that screening achieves this reduction in the context of routine healthcare, not only in the research context,” Duffy commented. “The results are generalizable to other populations, particularly in North America, Western Europe, and Australasia, where the epidemiology and demographics of breast cancer are similar,” said Duffy. “Clearly, more intensive screening is likely to achieve a greater benefit, but a trade-off between costs, both financial and human, and benefits always has to be made specific to each societal and healthcare environment.”

In Sweden, the policy regarding breast cancer screening is to screen women aged 40 to 54 years every 18 months. For those aged 55 to 69 years, screening is recommended every 24 months.

“The use of the incidence-based endpoints means that there is accurate classification of both the breast cancer cases and the whole study population in terms of exposure to screening and avoids a number of biases seen in other studies of service screening,” Duffy told Medscape Medical News.

“I have never seen persuasive evidence for the assertion that breast cancer screening does not reduce deaths from metastatic disease – indeed, the randomized trials seem to show the opposite,” said Duffy. “This may have arisen from a misunderstanding about the mechanism whereby screening works. It primarily works by diagnosing cancer early so that treatment is successful and recurrence with distant metastases, followed by death, does not occur some years later. I suspect some colleagues have confused this with distant metastases at initial diagnosis,” he added.
 

One expert questions methodology

One of the experts who was approached by Medscape Medical News to comment on the new study, Philippe Autier, MD, MPH, PhD, University of Strathclyde Institute of Global Public Health at the International Prevention Research Institute, Dardilly, France, questioned the methodology of the study. “This method is incorrect simply because women attending screening are different from women not attending screening,” he said. “The former are more health aware and have healthier behaviors than the latter, and this is a well-known fact and supported by the literature.”

Autier emphasized that it is practically impossible to control for that bias, which is known as confounding by indication.

“The statistical methods used for attenuating the so-called self-selection are very approximate and based on unverified assumptions,” he said. “For this reason, the Handbook on Breast Cancer Screening produced by the International Agency for Research on Cancer [IARC] clearly stated that ‘observational studies based on individual screening history, no matter how well designed and conducted, should not be regarded as providing evidence for an effect of screening,’ and the methodology in this paper has never been recommended by the IARC.”

A better way of conducting this type of study would have been to show the incidence trends of advanced-stage breast cancer in Sweden for the entire female population aged 40 years and older, he asserts. Autier used that methodology in his own study in the Netherlands, as previously reported by Medscape Medical News. That study found that in the Netherlands, screening mammography over a period of 24 years among women aged 50 to 74 years had little effect on reducing rates of advanced breast cancer or mortality from the disease.
 

Experts applaud the new findings

Three of the experts who were approached by Medscape Medical News to comment on the new findings applauded the efforts of Duffy and colleagues in providing evidence that mammography can reduce breast cancer–related mortality.

Marie Quinn, MD, director of diagnostic radiology at Roswell Park Comprehensive Cancer Center, Buffalo, New York, said this study adds to the growing body of scientific evidence that confirms that women who undergo regular screening mammography significantly reduce their risk of dying from breast cancer.

“Women who underwent regular screening also had a 25% reduction in the incidence of advanced-stage breast cancer,” she said. “This is important, because breast cancers are less fatal and often require less treatment when picked up at an earlier stage. We know the risk reduction benefit detected in this well-designed study can be attributed to screening mammography and not advances in cancer treatment, due to the long-term follow-up and outcome of cancer death within 10 years.”

The findings from this study support the guidelines recommending routine screening mammography in the United States, Quinn continued, but she pointed out that some aspects of screening (e.g., the age at which to begin screening and how often to screen) can vary. “This can be confusing for patients and providers,” she said. “Overall, research has shown us that women who undergo regular screening mammograms reduce their risk of dying from breast cancer. For women of average risk, the benefit of mammography is maximized with annual screening beginning at age 40,” she said.

Jay A. Baker, MD, FACR, FSBI, chief of the Division of Breast Imaging at Duke University Medical Center, Durham, North Carolina, emphasized that this is yet another study that confirms that the improvement in breast cancer mortality is not the result of improved treatments alone, as some have speculated. “Others have tried to model the benefit of screening vs treatment, but this study is a more direct measurement,” he said. “This conclusion is important for both patients and physicians to hear.”

Although the study strongly supports regular screening for all women, it does not specifically address which set of screening guidelines is optimal, Baker commented. “Fortunately, even though some organizations in the US curiously suggest a delayed start to screening, all organizations and professional societies agree that the most lives and the most years of life are saved by yearly screening beginning at age 40,” he added. “This new study tells us that new treatments alone aren’t enough and confirms that screening saves at least one-third more lives.”

Another expert, Bonnie N. Joe, MD, PhD, professor in residence and chief of breast imaging in the Department of Radiology and Biomedical Imaging at the University of California, San Francisco, agreed that the study shows the mortality benefits of regular screening mammography. “Notably, these benefits were related to participation in mammography screening and independent of any advances in treatment,” she said, “And these findings in this study support regular screening mammography to reduce advanced-stage breast cancers and to reduce a woman’s risk of dying from breast cancer.”

Joe noted that overall, this was a “well-done, large-scale screening study with long-term outcomes and should be applicable to other populations. In the US, we know that peak cancer incidence is in the 40s for minority women, and the results of this study support regular screening starting at 40.”

The study was supported by the American Cancer Society through a gift from the Longaberger Company’s Horizon of Hope Campaign. Additional financial support was provided by Brostcancerförbundet, Sweden. Duffy, Autier, Quinn, Joe, and Baker have disclosed no relevant financial relationships. One coauthor of the study has disclosed relationships with industry, as noted in the original article.

This article first appeared on Medscape.com.

New data from a large Swedish study show that mammography screening for breast cancer reduces the rate of both advanced and fatal breast cancer.

Three experts who were approached by Medscape Medical News say this is further evidence that regular screening mammography significantly reduces the risk of dying from breast cancer, but one expert questioned the methodology used in the study.

The primary goal of cancer screening is to detect tumors at an early stage, when they are most treatable. The hope is that this will reduce the number of advanced cancers associated with poor prognosis and hence the risk of dying from that cancer.

So far, for mammography, the data have been somewhat conflicting. For example, some evidence suggests that widespread breast cancer screening may catch more small, slow-growing tumors that are unlikely to be fatal but will not curb the number of cancers that are diagnosed at a late stage.

The new study, published online in Cancer, refutes this view.

It followed a Swedish cohort of 549,091 women (covering approximately 30% of the Swedish screening-eligible population) who underwent regular mammography.

For the women in this cohort, there was a statistically significant 41% reduction in the risk of dying of breast cancer within 10 years and a 25% reduction in the incidence of advanced disease, compared to women who did not undergo screening. “Even in this age of effective treatments, early detection confers a substantial and significant additional reduction in risk of dying from breast cancer,” said lead author Stephen W. Duffy, MSc, from the Center for Cancer Prevention at Queen Mary University, London, United Kingdom.

The current study confirms the findings of a smaller earlier study (Cancer. 2019;125:515-23) from the same investigators. “It finds the same result with an extremely large evidence base, with more than half a million women, and it also adds further to the evidence that screening achieves this reduction in the context of routine healthcare, not only in the research context,” Duffy commented. “The results are generalizable to other populations, particularly in North America, Western Europe, and Australasia, where the epidemiology and demographics of breast cancer are similar,” said Duffy. “Clearly, more intensive screening is likely to achieve a greater benefit, but a trade-off between costs, both financial and human, and benefits always has to be made specific to each societal and healthcare environment.”

In Sweden, the policy regarding breast cancer screening is to screen women aged 40 to 54 years every 18 months. For those aged 55 to 69 years, screening is recommended every 24 months.

“The use of the incidence-based endpoints means that there is accurate classification of both the breast cancer cases and the whole study population in terms of exposure to screening and avoids a number of biases seen in other studies of service screening,” Duffy told Medscape Medical News.

“I have never seen persuasive evidence for the assertion that breast cancer screening does not reduce deaths from metastatic disease – indeed, the randomized trials seem to show the opposite,” said Duffy. “This may have arisen from a misunderstanding about the mechanism whereby screening works. It primarily works by diagnosing cancer early so that treatment is successful and recurrence with distant metastases, followed by death, does not occur some years later. I suspect some colleagues have confused this with distant metastases at initial diagnosis,” he added.
 

One expert questions methodology

One of the experts who was approached by Medscape Medical News to comment on the new study, Philippe Autier, MD, MPH, PhD, University of Strathclyde Institute of Global Public Health at the International Prevention Research Institute, Dardilly, France, questioned the methodology of the study. “This method is incorrect simply because women attending screening are different from women not attending screening,” he said. “The former are more health aware and have healthier behaviors than the latter, and this is a well-known fact and supported by the literature.”

Autier emphasized that it is practically impossible to control for that bias, which is known as confounding by indication.

“The statistical methods used for attenuating the so-called self-selection are very approximate and based on unverified assumptions,” he said. “For this reason, the Handbook on Breast Cancer Screening produced by the International Agency for Research on Cancer [IARC] clearly stated that ‘observational studies based on individual screening history, no matter how well designed and conducted, should not be regarded as providing evidence for an effect of screening,’ and the methodology in this paper has never been recommended by the IARC.”

A better way of conducting this type of study would have been to show the incidence trends of advanced-stage breast cancer in Sweden for the entire female population aged 40 years and older, he asserts. Autier used that methodology in his own study in the Netherlands, as previously reported by Medscape Medical News. That study found that in the Netherlands, screening mammography over a period of 24 years among women aged 50 to 74 years had little effect on reducing rates of advanced breast cancer or mortality from the disease.
 

Experts applaud the new findings

Three of the experts who were approached by Medscape Medical News to comment on the new findings applauded the efforts of Duffy and colleagues in providing evidence that mammography can reduce breast cancer–related mortality.

Marie Quinn, MD, director of diagnostic radiology at Roswell Park Comprehensive Cancer Center, Buffalo, New York, said this study adds to the growing body of scientific evidence that confirms that women who undergo regular screening mammography significantly reduce their risk of dying from breast cancer.

“Women who underwent regular screening also had a 25% reduction in the incidence of advanced-stage breast cancer,” she said. “This is important, because breast cancers are less fatal and often require less treatment when picked up at an earlier stage. We know the risk reduction benefit detected in this well-designed study can be attributed to screening mammography and not advances in cancer treatment, due to the long-term follow-up and outcome of cancer death within 10 years.”

The findings from this study support the guidelines recommending routine screening mammography in the United States, Quinn continued, but she pointed out that some aspects of screening (e.g., the age at which to begin screening and how often to screen) can vary. “This can be confusing for patients and providers,” she said. “Overall, research has shown us that women who undergo regular screening mammograms reduce their risk of dying from breast cancer. For women of average risk, the benefit of mammography is maximized with annual screening beginning at age 40,” she said.

Jay A. Baker, MD, FACR, FSBI, chief of the Division of Breast Imaging at Duke University Medical Center, Durham, North Carolina, emphasized that this is yet another study that confirms that the improvement in breast cancer mortality is not the result of improved treatments alone, as some have speculated. “Others have tried to model the benefit of screening vs treatment, but this study is a more direct measurement,” he said. “This conclusion is important for both patients and physicians to hear.”

Although the study strongly supports regular screening for all women, it does not specifically address which set of screening guidelines is optimal, Baker commented. “Fortunately, even though some organizations in the US curiously suggest a delayed start to screening, all organizations and professional societies agree that the most lives and the most years of life are saved by yearly screening beginning at age 40,” he added. “This new study tells us that new treatments alone aren’t enough and confirms that screening saves at least one-third more lives.”

Another expert, Bonnie N. Joe, MD, PhD, professor in residence and chief of breast imaging in the Department of Radiology and Biomedical Imaging at the University of California, San Francisco, agreed that the study shows the mortality benefits of regular screening mammography. “Notably, these benefits were related to participation in mammography screening and independent of any advances in treatment,” she said, “And these findings in this study support regular screening mammography to reduce advanced-stage breast cancers and to reduce a woman’s risk of dying from breast cancer.”

Joe noted that overall, this was a “well-done, large-scale screening study with long-term outcomes and should be applicable to other populations. In the US, we know that peak cancer incidence is in the 40s for minority women, and the results of this study support regular screening starting at 40.”

The study was supported by the American Cancer Society through a gift from the Longaberger Company’s Horizon of Hope Campaign. Additional financial support was provided by Brostcancerförbundet, Sweden. Duffy, Autier, Quinn, Joe, and Baker have disclosed no relevant financial relationships. One coauthor of the study has disclosed relationships with industry, as noted in the original article.

This article first appeared on Medscape.com.

New data from a large Swedish study show that mammography screening for breast cancer reduces the rate of both advanced and fatal breast cancer.

Three experts who were approached by Medscape Medical News say this is further evidence that regular screening mammography significantly reduces the risk of dying from breast cancer, but one expert questioned the methodology used in the study.

The primary goal of cancer screening is to detect tumors at an early stage, when they are most treatable. The hope is that this will reduce the number of advanced cancers associated with poor prognosis and hence the risk of dying from that cancer.

So far, for mammography, the data have been somewhat conflicting. For example, some evidence suggests that widespread breast cancer screening may catch more small, slow-growing tumors that are unlikely to be fatal but will not curb the number of cancers that are diagnosed at a late stage.

The new study, published online in Cancer, refutes this view.

It followed a Swedish cohort of 549,091 women (covering approximately 30% of the Swedish screening-eligible population) who underwent regular mammography.

For the women in this cohort, there was a statistically significant 41% reduction in the risk of dying of breast cancer within 10 years and a 25% reduction in the incidence of advanced disease, compared to women who did not undergo screening. “Even in this age of effective treatments, early detection confers a substantial and significant additional reduction in risk of dying from breast cancer,” said lead author Stephen W. Duffy, MSc, from the Center for Cancer Prevention at Queen Mary University, London, United Kingdom.

The current study confirms the findings of a smaller earlier study (Cancer. 2019;125:515-23) from the same investigators. “It finds the same result with an extremely large evidence base, with more than half a million women, and it also adds further to the evidence that screening achieves this reduction in the context of routine healthcare, not only in the research context,” Duffy commented. “The results are generalizable to other populations, particularly in North America, Western Europe, and Australasia, where the epidemiology and demographics of breast cancer are similar,” said Duffy. “Clearly, more intensive screening is likely to achieve a greater benefit, but a trade-off between costs, both financial and human, and benefits always has to be made specific to each societal and healthcare environment.”

In Sweden, the policy regarding breast cancer screening is to screen women aged 40 to 54 years every 18 months. For those aged 55 to 69 years, screening is recommended every 24 months.

“The use of the incidence-based endpoints means that there is accurate classification of both the breast cancer cases and the whole study population in terms of exposure to screening and avoids a number of biases seen in other studies of service screening,” Duffy told Medscape Medical News.

“I have never seen persuasive evidence for the assertion that breast cancer screening does not reduce deaths from metastatic disease – indeed, the randomized trials seem to show the opposite,” said Duffy. “This may have arisen from a misunderstanding about the mechanism whereby screening works. It primarily works by diagnosing cancer early so that treatment is successful and recurrence with distant metastases, followed by death, does not occur some years later. I suspect some colleagues have confused this with distant metastases at initial diagnosis,” he added.
 

One expert questions methodology

One of the experts who was approached by Medscape Medical News to comment on the new study, Philippe Autier, MD, MPH, PhD, University of Strathclyde Institute of Global Public Health at the International Prevention Research Institute, Dardilly, France, questioned the methodology of the study. “This method is incorrect simply because women attending screening are different from women not attending screening,” he said. “The former are more health aware and have healthier behaviors than the latter, and this is a well-known fact and supported by the literature.”

Autier emphasized that it is practically impossible to control for that bias, which is known as confounding by indication.

“The statistical methods used for attenuating the so-called self-selection are very approximate and based on unverified assumptions,” he said. “For this reason, the Handbook on Breast Cancer Screening produced by the International Agency for Research on Cancer [IARC] clearly stated that ‘observational studies based on individual screening history, no matter how well designed and conducted, should not be regarded as providing evidence for an effect of screening,’ and the methodology in this paper has never been recommended by the IARC.”

A better way of conducting this type of study would have been to show the incidence trends of advanced-stage breast cancer in Sweden for the entire female population aged 40 years and older, he asserts. Autier used that methodology in his own study in the Netherlands, as previously reported by Medscape Medical News. That study found that in the Netherlands, screening mammography over a period of 24 years among women aged 50 to 74 years had little effect on reducing rates of advanced breast cancer or mortality from the disease.
 

Experts applaud the new findings

Three of the experts who were approached by Medscape Medical News to comment on the new findings applauded the efforts of Duffy and colleagues in providing evidence that mammography can reduce breast cancer–related mortality.

Marie Quinn, MD, director of diagnostic radiology at Roswell Park Comprehensive Cancer Center, Buffalo, New York, said this study adds to the growing body of scientific evidence that confirms that women who undergo regular screening mammography significantly reduce their risk of dying from breast cancer.

“Women who underwent regular screening also had a 25% reduction in the incidence of advanced-stage breast cancer,” she said. “This is important, because breast cancers are less fatal and often require less treatment when picked up at an earlier stage. We know the risk reduction benefit detected in this well-designed study can be attributed to screening mammography and not advances in cancer treatment, due to the long-term follow-up and outcome of cancer death within 10 years.”

The findings from this study support the guidelines recommending routine screening mammography in the United States, Quinn continued, but she pointed out that some aspects of screening (e.g., the age at which to begin screening and how often to screen) can vary. “This can be confusing for patients and providers,” she said. “Overall, research has shown us that women who undergo regular screening mammograms reduce their risk of dying from breast cancer. For women of average risk, the benefit of mammography is maximized with annual screening beginning at age 40,” she said.

Jay A. Baker, MD, FACR, FSBI, chief of the Division of Breast Imaging at Duke University Medical Center, Durham, North Carolina, emphasized that this is yet another study that confirms that the improvement in breast cancer mortality is not the result of improved treatments alone, as some have speculated. “Others have tried to model the benefit of screening vs treatment, but this study is a more direct measurement,” he said. “This conclusion is important for both patients and physicians to hear.”

Although the study strongly supports regular screening for all women, it does not specifically address which set of screening guidelines is optimal, Baker commented. “Fortunately, even though some organizations in the US curiously suggest a delayed start to screening, all organizations and professional societies agree that the most lives and the most years of life are saved by yearly screening beginning at age 40,” he added. “This new study tells us that new treatments alone aren’t enough and confirms that screening saves at least one-third more lives.”

Another expert, Bonnie N. Joe, MD, PhD, professor in residence and chief of breast imaging in the Department of Radiology and Biomedical Imaging at the University of California, San Francisco, agreed that the study shows the mortality benefits of regular screening mammography. “Notably, these benefits were related to participation in mammography screening and independent of any advances in treatment,” she said, “And these findings in this study support regular screening mammography to reduce advanced-stage breast cancers and to reduce a woman’s risk of dying from breast cancer.”

Joe noted that overall, this was a “well-done, large-scale screening study with long-term outcomes and should be applicable to other populations. In the US, we know that peak cancer incidence is in the 40s for minority women, and the results of this study support regular screening starting at 40.”

The study was supported by the American Cancer Society through a gift from the Longaberger Company’s Horizon of Hope Campaign. Additional financial support was provided by Brostcancerförbundet, Sweden. Duffy, Autier, Quinn, Joe, and Baker have disclosed no relevant financial relationships. One coauthor of the study has disclosed relationships with industry, as noted in the original article.

This article first appeared on Medscape.com.

Triple-negative breast cancer (TNBC) is a particularly aggressive form of this disease, with a poor prognosis, so there is great interest in any new treatment approach. Immunotherapy has raised hopes in TNBC, but more recently, studies have produced conflicting results.

New results show that adding a novel immune activator, Imprime PGG (Biothera), to immunotherapy with pembrolizumab (Keytruda, Merck) appears to improve the clinical benefit. The overall survival seen with the combination was twice that seen in a separate trial with pembrolizumab alone.

The new results were presented during the American Association for Cancer Research (AACR) virtual annual meeting I.

They come from the IMPRIME 1 trial, conducted in 44 women with metastatic TNBC who had anti-glucan antibodies.

“These were patients who had had prior chemotherapy and had extensive disease, including the majority with visceral disease and even liver metastasis,” said investigator Steven O’Day, MD, from the John Wayne Cancer Institute in Santa Monica, California.

All patients were treated with the combination. “We see encouraging clinical benefit evidence across all of our clinical measurements: response, durable response, and median and overall survival compared to historical single-agent [anti] PD-1 in a similar metastatic triple-negative breast cancer population,” he said.

At a median follow-up of 22.5 months, median overall survival with the combination among the 44 patients treated was 16.4 months.

In contrast, in the Keynote-086 trial of pembrolizumab monotherapy in patients with TNBC, median overall survival was 9 months, O’Day said.

He emphasized, however, that the IMPRIME 1 trial was not designed or powered to directly compare the combination therapy with pembrolizumab monotherapy.

Clinical benefit with the combination was particularly pronounced for patients who were so-called TNBC “converters” — that is, they originally had estrogen receptor (ER)-positive tumors that had progressed on endocrine therapy and, prior to starting treatment with Imprime PGG and pembrolizumab, they had biopsy results confirming TNBC, O’Day said.

The overall response rate (ORR) for all 44 patients included in the efficacy analysis was 15.9%. But among the 12 patients whose disease converted from ER-positive to TNBC after endocrine therapy, six had a response, for an ORR of 50% and a median overall survival of 17.1 months.

“It is not clear whether hormone resistance may have led to the increased responses versus secondary triple-negative status, but it is of great interest to us,” O’Day said.
 

Why This Special Benefit?

Invited discussant Ben Ho Park, MD, PhD, from Vanderbilt University Medical Center in Nashville, Tennessee, commented that the finding of special benefit among TNBC converters raises the question of biomarkers to determine which patients might most benefit from the combination.

“We already know that anti-beta-glucan antibodies were required to be actually eligible for this study, but is it that, in combination with immune activation, or prior ER-positive disease?” he said. “What about the role of PD-L1 staining? Can we actually combine all this data to come up with some sort of predictive score for whether or not a patient is more or less likely to respond, and more or less likely to have toxicities?”

Yeast-Derived Compound

Imprime PGG is a novel beta-glucan isolated from the cell walls of saccharomyces yeast that binds to endogenous anti-beta-glucan antibodies to form an immune complex.

The immune complex, which is the active drug, binds to a receptor known as dectin-1 to activate innate immunity and reprogram the immunosuppressive tumor microenvironment, enhance antigen presentation, and trigger T-cell activation to improve the efficacy of immune checkpoint inhibitor therapy, O’Day explained.

The complex has been administered to date to approximately 600 healthy volunteers and patients. In these studies, it was administered intravenously at doses of 2 mg/kg to 6 mg/kg weekly as monotherapy or in combination with anti-angiogenic antibodies or tumor-targeting antibodies, with or without chemotherapy.

Studies in volunteers showed that the complex activated innate immunity. Patients have tolerated it well, with no significant safety signals in either monotherapy or combination, with grade 1 or 2 infusion-related reactions being the most common adverse events to date, O’Day reported.

Study Details

Imprime 1 was a single-arm phase 2 trial enrolling 44 women with TNBC who had received at least one prior line of treatment, but not with an immune checkpoint inhibitor. They were all required to have anti-beta-glucan antibody levels of at least 20 mcg/mL.

All patients received the combination, which comprised Imprime PGG 4 mg/kg weekly plus pembrolizumab 200 mg IV every 3 weeks.

Twenty one patients were under age 50 years, and 23 were 50 years old and older. Seventeen patients were premenopausal, and 27 were postmenopausal. In all, 15 patients had more than three prior lines of therapy for metastatic disease, 30 had visceral disease, and 12 had liver metastases; only four had metastases confined to lymph nodes.

As noted above, median overall survival for all patients was 16.4 months. The ORR was 15.9%, and the disease control rate (a combination of complete and partial responses plus stable disease) was 25%. The median progression-free survival was 2.7 months (vs 2 months in Keynote-086).

In all, 39 of the 44 patients had treatment-related adverse events, with the most common being nausea, back pain, chills, fatigue, diarrhea, arthralgia, and headache. Four patients had grade 3 or 4 events, which included an infusion-related reaction, hyperglycemia, pericarditis, and pancreatitis.

Infusion-related reactions were seen in 27 patients, but only one of these reactions was grade 3 or 4.

The most common immune-mediated events were grade 1 or 2 thyroid dysfunction, which is commonly seen with PD-1 inhibitors, and there were single low-grade events of pancreatitis, pneumonitis, and pericarditis “most likely related to PD-1 inhibitor therapy,” O’Day said.

Translational data showed that innate and adaptive immunity in peripheral blood correlates with clinical benefit, with longer overall survival among patients with either monocyte activation (P = .0045) or T-cell activation (P = .012) compared with patients without activation of those components.

Taken together, the findings suggest that larger controlled studies of the combination are warranted, O’Day said.

The study was sponsored by Biothera and Merck. O’Day disclosed advisory board activities and research funding from both companies and others, and consulting for Biothera. Park disclosed royalties and consulting activities from several companies, not including the Imprime 1 sponsors.
 

This article first appeared on Medscape.com.

Triple-negative breast cancer (TNBC) is a particularly aggressive form of this disease, with a poor prognosis, so there is great interest in any new treatment approach. Immunotherapy has raised hopes in TNBC, but more recently, studies have produced conflicting results.

New results show that adding a novel immune activator, Imprime PGG (Biothera), to immunotherapy with pembrolizumab (Keytruda, Merck) appears to improve the clinical benefit. The overall survival seen with the combination was twice that seen in a separate trial with pembrolizumab alone.

The new results were presented during the American Association for Cancer Research (AACR) virtual annual meeting I.

They come from the IMPRIME 1 trial, conducted in 44 women with metastatic TNBC who had anti-glucan antibodies.

“These were patients who had had prior chemotherapy and had extensive disease, including the majority with visceral disease and even liver metastasis,” said investigator Steven O’Day, MD, from the John Wayne Cancer Institute in Santa Monica, California.

All patients were treated with the combination. “We see encouraging clinical benefit evidence across all of our clinical measurements: response, durable response, and median and overall survival compared to historical single-agent [anti] PD-1 in a similar metastatic triple-negative breast cancer population,” he said.

At a median follow-up of 22.5 months, median overall survival with the combination among the 44 patients treated was 16.4 months.

In contrast, in the Keynote-086 trial of pembrolizumab monotherapy in patients with TNBC, median overall survival was 9 months, O’Day said.

He emphasized, however, that the IMPRIME 1 trial was not designed or powered to directly compare the combination therapy with pembrolizumab monotherapy.

Clinical benefit with the combination was particularly pronounced for patients who were so-called TNBC “converters” — that is, they originally had estrogen receptor (ER)-positive tumors that had progressed on endocrine therapy and, prior to starting treatment with Imprime PGG and pembrolizumab, they had biopsy results confirming TNBC, O’Day said.

The overall response rate (ORR) for all 44 patients included in the efficacy analysis was 15.9%. But among the 12 patients whose disease converted from ER-positive to TNBC after endocrine therapy, six had a response, for an ORR of 50% and a median overall survival of 17.1 months.

“It is not clear whether hormone resistance may have led to the increased responses versus secondary triple-negative status, but it is of great interest to us,” O’Day said.
 

Why This Special Benefit?

Invited discussant Ben Ho Park, MD, PhD, from Vanderbilt University Medical Center in Nashville, Tennessee, commented that the finding of special benefit among TNBC converters raises the question of biomarkers to determine which patients might most benefit from the combination.

“We already know that anti-beta-glucan antibodies were required to be actually eligible for this study, but is it that, in combination with immune activation, or prior ER-positive disease?” he said. “What about the role of PD-L1 staining? Can we actually combine all this data to come up with some sort of predictive score for whether or not a patient is more or less likely to respond, and more or less likely to have toxicities?”

Yeast-Derived Compound

Imprime PGG is a novel beta-glucan isolated from the cell walls of saccharomyces yeast that binds to endogenous anti-beta-glucan antibodies to form an immune complex.

The immune complex, which is the active drug, binds to a receptor known as dectin-1 to activate innate immunity and reprogram the immunosuppressive tumor microenvironment, enhance antigen presentation, and trigger T-cell activation to improve the efficacy of immune checkpoint inhibitor therapy, O’Day explained.

The complex has been administered to date to approximately 600 healthy volunteers and patients. In these studies, it was administered intravenously at doses of 2 mg/kg to 6 mg/kg weekly as monotherapy or in combination with anti-angiogenic antibodies or tumor-targeting antibodies, with or without chemotherapy.

Studies in volunteers showed that the complex activated innate immunity. Patients have tolerated it well, with no significant safety signals in either monotherapy or combination, with grade 1 or 2 infusion-related reactions being the most common adverse events to date, O’Day reported.

Study Details

Imprime 1 was a single-arm phase 2 trial enrolling 44 women with TNBC who had received at least one prior line of treatment, but not with an immune checkpoint inhibitor. They were all required to have anti-beta-glucan antibody levels of at least 20 mcg/mL.

All patients received the combination, which comprised Imprime PGG 4 mg/kg weekly plus pembrolizumab 200 mg IV every 3 weeks.

Twenty one patients were under age 50 years, and 23 were 50 years old and older. Seventeen patients were premenopausal, and 27 were postmenopausal. In all, 15 patients had more than three prior lines of therapy for metastatic disease, 30 had visceral disease, and 12 had liver metastases; only four had metastases confined to lymph nodes.

As noted above, median overall survival for all patients was 16.4 months. The ORR was 15.9%, and the disease control rate (a combination of complete and partial responses plus stable disease) was 25%. The median progression-free survival was 2.7 months (vs 2 months in Keynote-086).

In all, 39 of the 44 patients had treatment-related adverse events, with the most common being nausea, back pain, chills, fatigue, diarrhea, arthralgia, and headache. Four patients had grade 3 or 4 events, which included an infusion-related reaction, hyperglycemia, pericarditis, and pancreatitis.

Infusion-related reactions were seen in 27 patients, but only one of these reactions was grade 3 or 4.

The most common immune-mediated events were grade 1 or 2 thyroid dysfunction, which is commonly seen with PD-1 inhibitors, and there were single low-grade events of pancreatitis, pneumonitis, and pericarditis “most likely related to PD-1 inhibitor therapy,” O’Day said.

Translational data showed that innate and adaptive immunity in peripheral blood correlates with clinical benefit, with longer overall survival among patients with either monocyte activation (P = .0045) or T-cell activation (P = .012) compared with patients without activation of those components.

Taken together, the findings suggest that larger controlled studies of the combination are warranted, O’Day said.

The study was sponsored by Biothera and Merck. O’Day disclosed advisory board activities and research funding from both companies and others, and consulting for Biothera. Park disclosed royalties and consulting activities from several companies, not including the Imprime 1 sponsors.
 

This article first appeared on Medscape.com.

Triple-negative breast cancer (TNBC) is a particularly aggressive form of this disease, with a poor prognosis, so there is great interest in any new treatment approach. Immunotherapy has raised hopes in TNBC, but more recently, studies have produced conflicting results.

New results show that adding a novel immune activator, Imprime PGG (Biothera), to immunotherapy with pembrolizumab (Keytruda, Merck) appears to improve the clinical benefit. The overall survival seen with the combination was twice that seen in a separate trial with pembrolizumab alone.

The new results were presented during the American Association for Cancer Research (AACR) virtual annual meeting I.

They come from the IMPRIME 1 trial, conducted in 44 women with metastatic TNBC who had anti-glucan antibodies.

“These were patients who had had prior chemotherapy and had extensive disease, including the majority with visceral disease and even liver metastasis,” said investigator Steven O’Day, MD, from the John Wayne Cancer Institute in Santa Monica, California.

All patients were treated with the combination. “We see encouraging clinical benefit evidence across all of our clinical measurements: response, durable response, and median and overall survival compared to historical single-agent [anti] PD-1 in a similar metastatic triple-negative breast cancer population,” he said.

At a median follow-up of 22.5 months, median overall survival with the combination among the 44 patients treated was 16.4 months.

In contrast, in the Keynote-086 trial of pembrolizumab monotherapy in patients with TNBC, median overall survival was 9 months, O’Day said.

He emphasized, however, that the IMPRIME 1 trial was not designed or powered to directly compare the combination therapy with pembrolizumab monotherapy.

Clinical benefit with the combination was particularly pronounced for patients who were so-called TNBC “converters” — that is, they originally had estrogen receptor (ER)-positive tumors that had progressed on endocrine therapy and, prior to starting treatment with Imprime PGG and pembrolizumab, they had biopsy results confirming TNBC, O’Day said.

The overall response rate (ORR) for all 44 patients included in the efficacy analysis was 15.9%. But among the 12 patients whose disease converted from ER-positive to TNBC after endocrine therapy, six had a response, for an ORR of 50% and a median overall survival of 17.1 months.

“It is not clear whether hormone resistance may have led to the increased responses versus secondary triple-negative status, but it is of great interest to us,” O’Day said.
 

Why This Special Benefit?

Invited discussant Ben Ho Park, MD, PhD, from Vanderbilt University Medical Center in Nashville, Tennessee, commented that the finding of special benefit among TNBC converters raises the question of biomarkers to determine which patients might most benefit from the combination.

“We already know that anti-beta-glucan antibodies were required to be actually eligible for this study, but is it that, in combination with immune activation, or prior ER-positive disease?” he said. “What about the role of PD-L1 staining? Can we actually combine all this data to come up with some sort of predictive score for whether or not a patient is more or less likely to respond, and more or less likely to have toxicities?”

Yeast-Derived Compound

Imprime PGG is a novel beta-glucan isolated from the cell walls of saccharomyces yeast that binds to endogenous anti-beta-glucan antibodies to form an immune complex.

The immune complex, which is the active drug, binds to a receptor known as dectin-1 to activate innate immunity and reprogram the immunosuppressive tumor microenvironment, enhance antigen presentation, and trigger T-cell activation to improve the efficacy of immune checkpoint inhibitor therapy, O’Day explained.

The complex has been administered to date to approximately 600 healthy volunteers and patients. In these studies, it was administered intravenously at doses of 2 mg/kg to 6 mg/kg weekly as monotherapy or in combination with anti-angiogenic antibodies or tumor-targeting antibodies, with or without chemotherapy.

Studies in volunteers showed that the complex activated innate immunity. Patients have tolerated it well, with no significant safety signals in either monotherapy or combination, with grade 1 or 2 infusion-related reactions being the most common adverse events to date, O’Day reported.

Study Details

Imprime 1 was a single-arm phase 2 trial enrolling 44 women with TNBC who had received at least one prior line of treatment, but not with an immune checkpoint inhibitor. They were all required to have anti-beta-glucan antibody levels of at least 20 mcg/mL.

All patients received the combination, which comprised Imprime PGG 4 mg/kg weekly plus pembrolizumab 200 mg IV every 3 weeks.

Twenty one patients were under age 50 years, and 23 were 50 years old and older. Seventeen patients were premenopausal, and 27 were postmenopausal. In all, 15 patients had more than three prior lines of therapy for metastatic disease, 30 had visceral disease, and 12 had liver metastases; only four had metastases confined to lymph nodes.

As noted above, median overall survival for all patients was 16.4 months. The ORR was 15.9%, and the disease control rate (a combination of complete and partial responses plus stable disease) was 25%. The median progression-free survival was 2.7 months (vs 2 months in Keynote-086).

In all, 39 of the 44 patients had treatment-related adverse events, with the most common being nausea, back pain, chills, fatigue, diarrhea, arthralgia, and headache. Four patients had grade 3 or 4 events, which included an infusion-related reaction, hyperglycemia, pericarditis, and pancreatitis.

Infusion-related reactions were seen in 27 patients, but only one of these reactions was grade 3 or 4.

The most common immune-mediated events were grade 1 or 2 thyroid dysfunction, which is commonly seen with PD-1 inhibitors, and there were single low-grade events of pancreatitis, pneumonitis, and pericarditis “most likely related to PD-1 inhibitor therapy,” O’Day said.

Translational data showed that innate and adaptive immunity in peripheral blood correlates with clinical benefit, with longer overall survival among patients with either monocyte activation (P = .0045) or T-cell activation (P = .012) compared with patients without activation of those components.

Taken together, the findings suggest that larger controlled studies of the combination are warranted, O’Day said.

The study was sponsored by Biothera and Merck. O’Day disclosed advisory board activities and research funding from both companies and others, and consulting for Biothera. Park disclosed royalties and consulting activities from several companies, not including the Imprime 1 sponsors.
 

This article first appeared on Medscape.com.