Advanced and Metastatic Breast Cancer

Recommendations on the use of next-generation sequencing (NGS) tests for patients with metastatic cancer have been issued by the European Society for Medical Oncology, the first recommendations of their kind to be published by any medical society.

“Until now, there were no recommendations from scientific societies on how to use this technique in daily clinical practice to profile metastatic cancers,” Fernanda Mosele, MD, medical oncologist, Gustave Roussy, Villejuif, France, said in a statement.

NGS testing is already used extensively in oncology, particularly in metastatic cancer, she noted. The technology is used to assess the sequence of DNA in genes from a tumor tissue sample. Numerous genes can be quickly sequenced at the same time at relatively low cost. The results provide information on mutations that are present, which, in turn, helps with deciding which treatments to use, including drugs targeting the identified mutations.

“Our intent is that they [the guidelines] will unify decision-making about how NGS should be used for patients with metastatic cancer,” Dr. Mosele said.

The recommendations were published online August 25 in Annals of Oncology.

Overall, ESMO recommends the use of tumor multigene NGS for non–small cell lung cancer (NSCLC), prostate cancer, ovarian cancer, and cholangiocarcinoma.

For other cancers, the authors said that NGS is not recommended in clinical practice but could be used for research purposes.

However, patients should be informed that it is unlikely that test results would benefit them much personally.

Physicians and patients may decide together to subject the tumor to mutational testing using a large panel of genes, provided testing doesn’t burden the health care system with additional costs.

“This recommendation acknowledges that a small number of patients could benefit from a drug because they have a rare mutation,” Joaquin Mateo, MD, chair of the ESMO working group, said in a statement.

“So beyond the cancers in which everyone should receive NGS, there is room for physicians and patients to discuss the pros and cons of ordering these tests,” he added.

ESMO also does not recommend the use of off-label drugs matched to any genomic alteration detected by NGS unless an access program and a decisional procedure have been developed, either regionally or nationally.
 

No need for NGS testing of other cancers

In contrast to NSCLC, “there is currently no need to perform tumor multigene NGS for patients with mBC [metastatic breast cancer] in the context of daily practice,” ESMO stated.

This is largely because somatic sequencing cannot fully substitute for germline testing for BRCA status, and other mutations, such as HER2, can be detected using immunohistochemistry (IHC).

The same can be said for patients with metastatic gastric cancer, inasmuch as detection of alterations can and should be done using cheaper testing methods, ESMO pointed out.

However, ESMO members still emphasized that it’s important to include patients with metastatic breast cancer in molecular screening programs as well as in clinical trials testing targeted agents.

Similarly, there is no need to test metastatic colorectal cancer (mCRC) using multigene NGS in daily practice, inasmuch as most level 1 alterations in mCRC can be determined by IHC or PCR.

However, NGS can be considered as an alternative to PCR-based tests in mCRC, provided NGS is not associated with additional cost.

ESMO again recommended that research centers include mCRC patients in molecular screening programs in order for them to have access to innovative clinical trial agents.

As for advanced prostate cancer, ESMO does recommend that clinicians perform NGS on tissue samples to assess the tumor’s mutational status, at least for the presence of BRCA1 and BRCA2 mutations, when patients have access to the poly (ADP-ribose) polymerase inhibitors for treatment.

The authors cautioned, however, that this strategy is unlikely to be cost-effective, so larger panels should be used only when there are specific agreements with payers.

Multigene NGS is also not recommended for patients with advanced pancreatic ductal adenocarcinoma (PDAC), although ESMO points out that it is the role of research centers to propose multigene sequencing for these patients in the context of molecular screening programs.

This is again to facilitate access to innovative drugs for these patients.

Similar to recommendations for patients with advanced PDAC, patients with advanced hepatocellular carcinoma (HCC) do not need to have tumor multigene NGS either.

Considering the high unmet needs of HCC patients, ESMO feels that research centers should propose multigene sequencing to patients with advanced HCC in the context of molecular screening programs.

In contrast, ESMO recommended that tumor multigene NGS be used to detect actionable alterations in patients with advanced cholangiocarcinoma.

Again, they predict that this strategy is unlikely to be cost-effective, so larger panels should only be used if a specific agreement is in place with payers.

ESMO also assessed the frequency of level 1 alterations in less frequent tumor types, including ovarian cancers. Because BRCA1 and BRCA2 somatic mutations in ovarian tumors have been associated with increased response to the PARP inhibitors, the use of multigene NGS is justified with this malignancy, ESMO states.

The authors also recommend that tumor mutational burden be determined in cervical cancer, moderately differentiated neuroendocrine tumors, salivary cancers, vulvar cancer, and thyroid cancers.

Dr. Mosele has disclosed no relevant financial relationships. Many coauthors have relationships with the pharmaceutical industry, as listed in the article.

This article first appeared on Medscape.com.

Recommendations on the use of next-generation sequencing (NGS) tests for patients with metastatic cancer have been issued by the European Society for Medical Oncology, the first recommendations of their kind to be published by any medical society.

“Until now, there were no recommendations from scientific societies on how to use this technique in daily clinical practice to profile metastatic cancers,” Fernanda Mosele, MD, medical oncologist, Gustave Roussy, Villejuif, France, said in a statement.

NGS testing is already used extensively in oncology, particularly in metastatic cancer, she noted. The technology is used to assess the sequence of DNA in genes from a tumor tissue sample. Numerous genes can be quickly sequenced at the same time at relatively low cost. The results provide information on mutations that are present, which, in turn, helps with deciding which treatments to use, including drugs targeting the identified mutations.

“Our intent is that they [the guidelines] will unify decision-making about how NGS should be used for patients with metastatic cancer,” Dr. Mosele said.

The recommendations were published online August 25 in Annals of Oncology.

Overall, ESMO recommends the use of tumor multigene NGS for non–small cell lung cancer (NSCLC), prostate cancer, ovarian cancer, and cholangiocarcinoma.

For other cancers, the authors said that NGS is not recommended in clinical practice but could be used for research purposes.

However, patients should be informed that it is unlikely that test results would benefit them much personally.

Physicians and patients may decide together to subject the tumor to mutational testing using a large panel of genes, provided testing doesn’t burden the health care system with additional costs.

“This recommendation acknowledges that a small number of patients could benefit from a drug because they have a rare mutation,” Joaquin Mateo, MD, chair of the ESMO working group, said in a statement.

“So beyond the cancers in which everyone should receive NGS, there is room for physicians and patients to discuss the pros and cons of ordering these tests,” he added.

ESMO also does not recommend the use of off-label drugs matched to any genomic alteration detected by NGS unless an access program and a decisional procedure have been developed, either regionally or nationally.
 

No need for NGS testing of other cancers

In contrast to NSCLC, “there is currently no need to perform tumor multigene NGS for patients with mBC [metastatic breast cancer] in the context of daily practice,” ESMO stated.

This is largely because somatic sequencing cannot fully substitute for germline testing for BRCA status, and other mutations, such as HER2, can be detected using immunohistochemistry (IHC).

The same can be said for patients with metastatic gastric cancer, inasmuch as detection of alterations can and should be done using cheaper testing methods, ESMO pointed out.

However, ESMO members still emphasized that it’s important to include patients with metastatic breast cancer in molecular screening programs as well as in clinical trials testing targeted agents.

Similarly, there is no need to test metastatic colorectal cancer (mCRC) using multigene NGS in daily practice, inasmuch as most level 1 alterations in mCRC can be determined by IHC or PCR.

However, NGS can be considered as an alternative to PCR-based tests in mCRC, provided NGS is not associated with additional cost.

ESMO again recommended that research centers include mCRC patients in molecular screening programs in order for them to have access to innovative clinical trial agents.

As for advanced prostate cancer, ESMO does recommend that clinicians perform NGS on tissue samples to assess the tumor’s mutational status, at least for the presence of BRCA1 and BRCA2 mutations, when patients have access to the poly (ADP-ribose) polymerase inhibitors for treatment.

The authors cautioned, however, that this strategy is unlikely to be cost-effective, so larger panels should be used only when there are specific agreements with payers.

Multigene NGS is also not recommended for patients with advanced pancreatic ductal adenocarcinoma (PDAC), although ESMO points out that it is the role of research centers to propose multigene sequencing for these patients in the context of molecular screening programs.

This is again to facilitate access to innovative drugs for these patients.

Similar to recommendations for patients with advanced PDAC, patients with advanced hepatocellular carcinoma (HCC) do not need to have tumor multigene NGS either.

Considering the high unmet needs of HCC patients, ESMO feels that research centers should propose multigene sequencing to patients with advanced HCC in the context of molecular screening programs.

In contrast, ESMO recommended that tumor multigene NGS be used to detect actionable alterations in patients with advanced cholangiocarcinoma.

Again, they predict that this strategy is unlikely to be cost-effective, so larger panels should only be used if a specific agreement is in place with payers.

ESMO also assessed the frequency of level 1 alterations in less frequent tumor types, including ovarian cancers. Because BRCA1 and BRCA2 somatic mutations in ovarian tumors have been associated with increased response to the PARP inhibitors, the use of multigene NGS is justified with this malignancy, ESMO states.

The authors also recommend that tumor mutational burden be determined in cervical cancer, moderately differentiated neuroendocrine tumors, salivary cancers, vulvar cancer, and thyroid cancers.

Dr. Mosele has disclosed no relevant financial relationships. Many coauthors have relationships with the pharmaceutical industry, as listed in the article.

This article first appeared on Medscape.com.

Recommendations on the use of next-generation sequencing (NGS) tests for patients with metastatic cancer have been issued by the European Society for Medical Oncology, the first recommendations of their kind to be published by any medical society.

“Until now, there were no recommendations from scientific societies on how to use this technique in daily clinical practice to profile metastatic cancers,” Fernanda Mosele, MD, medical oncologist, Gustave Roussy, Villejuif, France, said in a statement.

NGS testing is already used extensively in oncology, particularly in metastatic cancer, she noted. The technology is used to assess the sequence of DNA in genes from a tumor tissue sample. Numerous genes can be quickly sequenced at the same time at relatively low cost. The results provide information on mutations that are present, which, in turn, helps with deciding which treatments to use, including drugs targeting the identified mutations.

“Our intent is that they [the guidelines] will unify decision-making about how NGS should be used for patients with metastatic cancer,” Dr. Mosele said.

The recommendations were published online August 25 in Annals of Oncology.

Overall, ESMO recommends the use of tumor multigene NGS for non–small cell lung cancer (NSCLC), prostate cancer, ovarian cancer, and cholangiocarcinoma.

For other cancers, the authors said that NGS is not recommended in clinical practice but could be used for research purposes.

However, patients should be informed that it is unlikely that test results would benefit them much personally.

Physicians and patients may decide together to subject the tumor to mutational testing using a large panel of genes, provided testing doesn’t burden the health care system with additional costs.

“This recommendation acknowledges that a small number of patients could benefit from a drug because they have a rare mutation,” Joaquin Mateo, MD, chair of the ESMO working group, said in a statement.

“So beyond the cancers in which everyone should receive NGS, there is room for physicians and patients to discuss the pros and cons of ordering these tests,” he added.

ESMO also does not recommend the use of off-label drugs matched to any genomic alteration detected by NGS unless an access program and a decisional procedure have been developed, either regionally or nationally.
 

No need for NGS testing of other cancers

In contrast to NSCLC, “there is currently no need to perform tumor multigene NGS for patients with mBC [metastatic breast cancer] in the context of daily practice,” ESMO stated.

This is largely because somatic sequencing cannot fully substitute for germline testing for BRCA status, and other mutations, such as HER2, can be detected using immunohistochemistry (IHC).

The same can be said for patients with metastatic gastric cancer, inasmuch as detection of alterations can and should be done using cheaper testing methods, ESMO pointed out.

However, ESMO members still emphasized that it’s important to include patients with metastatic breast cancer in molecular screening programs as well as in clinical trials testing targeted agents.

Similarly, there is no need to test metastatic colorectal cancer (mCRC) using multigene NGS in daily practice, inasmuch as most level 1 alterations in mCRC can be determined by IHC or PCR.

However, NGS can be considered as an alternative to PCR-based tests in mCRC, provided NGS is not associated with additional cost.

ESMO again recommended that research centers include mCRC patients in molecular screening programs in order for them to have access to innovative clinical trial agents.

As for advanced prostate cancer, ESMO does recommend that clinicians perform NGS on tissue samples to assess the tumor’s mutational status, at least for the presence of BRCA1 and BRCA2 mutations, when patients have access to the poly (ADP-ribose) polymerase inhibitors for treatment.

The authors cautioned, however, that this strategy is unlikely to be cost-effective, so larger panels should be used only when there are specific agreements with payers.

Multigene NGS is also not recommended for patients with advanced pancreatic ductal adenocarcinoma (PDAC), although ESMO points out that it is the role of research centers to propose multigene sequencing for these patients in the context of molecular screening programs.

This is again to facilitate access to innovative drugs for these patients.

Similar to recommendations for patients with advanced PDAC, patients with advanced hepatocellular carcinoma (HCC) do not need to have tumor multigene NGS either.

Considering the high unmet needs of HCC patients, ESMO feels that research centers should propose multigene sequencing to patients with advanced HCC in the context of molecular screening programs.

In contrast, ESMO recommended that tumor multigene NGS be used to detect actionable alterations in patients with advanced cholangiocarcinoma.

Again, they predict that this strategy is unlikely to be cost-effective, so larger panels should only be used if a specific agreement is in place with payers.

ESMO also assessed the frequency of level 1 alterations in less frequent tumor types, including ovarian cancers. Because BRCA1 and BRCA2 somatic mutations in ovarian tumors have been associated with increased response to the PARP inhibitors, the use of multigene NGS is justified with this malignancy, ESMO states.

The authors also recommend that tumor mutational burden be determined in cervical cancer, moderately differentiated neuroendocrine tumors, salivary cancers, vulvar cancer, and thyroid cancers.

Dr. Mosele has disclosed no relevant financial relationships. Many coauthors have relationships with the pharmaceutical industry, as listed in the article.

This article first appeared on Medscape.com.

The Food and Drug Administration recently announced two new types of cancer that can be treated by the anti–PD-1 antibody pembrolizumab.

The new indications expand the use of pembrolizumab (Keytruda) to include treatment of patients with unresectable or metastatic tumor mutational burden–high (TMB-H) solid tumors as well as patients with cutaneous squamous cell carcinoma (cSCC). The FDA announced the new indications just 8 days apart, on June 16 and June 24.

In addition, on June 29, the FDA approved a third new indication for pembrolizumab, this time as first-line treatment for patients with unresectable or metastatic microsatellite instability–high or mismatch repair–deficient colorectal cancer.



The new approvals add to a wide range of oncology indications for which pembrolizumab can be used.

Accelerated approval to treat solid tumors

The FDA granted accelerated approval for pembrolizumab to treat children and adults with unresectable or metastatic TMB-H solid tumors that progressed after previous treatment or in instances where there are no satisfactory alternative treatment options.

The tumor mutational burden must be confirmed by an FDA-approved test. To that end, the FDA approved the FoundationOneCDx assay, which is designed to help physicians determine which patients meet the threshold for TMB-H malignancies (10 or more mutations per megabase).

The efficacy of pembrolizumab in TMB-H solid tumors was investigated in 10 cohorts from the multicenter, open-label KEYNOTE-158 trial. Participants received 200 mg of pembrolizumab intravenously every 3 weeks until their disease progressed or they experienced unacceptable toxicity.

Within this population, 102 patients had tumors that met the TMB-H definition. In this group, the overall response rate was 29%, including a 25% partial response rate and a 4% complete response rate.

The median duration of response was not reached, but 57% of participants experienced a response lasting 12 months or longer, and 50% had a response lasting 24 months or longer.

The most common adverse events associated with pembrolizumab in this trial were fatigue, musculoskeletal pain, decreased appetite, pruritus, diarrhea, nausea, rash, pyrexia, cough, dyspnea, constipation, pain, and abdominal pain. Pembrolizumab is associated with immune-mediated side effects, including pneumonitis, colitis, hepatitis, endocrinopathies, nephritis, and skin adverse reactions, the FDA noted.

Safety and efficacy of pembrolizumab in pediatric patients with TMB-H central nervous system cancers have not been established.
 

New option for recurrent or metastatic cSCC

Physicians treating patients with cSCC that is not curable by surgery or radiation now have pembrolizumab to consider as another treatment option.

The cSCC approval is based on results of the multicenter, open-label KEYNOTE-629 trial. The dosage regimen was 200 mg of pembrolizumab intravenously every 3 weeks until cancer progressed, unacceptable toxicity arose, or 24 months of treatment were completed.

The objective response rate was 34%, and the median duration of response was not reached.

Adverse events were similar to those occurring in patients who received pembrolizumab as a single agent in other clinical trials, the FDA noted.

The Food and Drug Administration recently announced two new types of cancer that can be treated by the anti–PD-1 antibody pembrolizumab.

The new indications expand the use of pembrolizumab (Keytruda) to include treatment of patients with unresectable or metastatic tumor mutational burden–high (TMB-H) solid tumors as well as patients with cutaneous squamous cell carcinoma (cSCC). The FDA announced the new indications just 8 days apart, on June 16 and June 24.

In addition, on June 29, the FDA approved a third new indication for pembrolizumab, this time as first-line treatment for patients with unresectable or metastatic microsatellite instability–high or mismatch repair–deficient colorectal cancer.



The new approvals add to a wide range of oncology indications for which pembrolizumab can be used.

Accelerated approval to treat solid tumors

The FDA granted accelerated approval for pembrolizumab to treat children and adults with unresectable or metastatic TMB-H solid tumors that progressed after previous treatment or in instances where there are no satisfactory alternative treatment options.

The tumor mutational burden must be confirmed by an FDA-approved test. To that end, the FDA approved the FoundationOneCDx assay, which is designed to help physicians determine which patients meet the threshold for TMB-H malignancies (10 or more mutations per megabase).

The efficacy of pembrolizumab in TMB-H solid tumors was investigated in 10 cohorts from the multicenter, open-label KEYNOTE-158 trial. Participants received 200 mg of pembrolizumab intravenously every 3 weeks until their disease progressed or they experienced unacceptable toxicity.

Within this population, 102 patients had tumors that met the TMB-H definition. In this group, the overall response rate was 29%, including a 25% partial response rate and a 4% complete response rate.

The median duration of response was not reached, but 57% of participants experienced a response lasting 12 months or longer, and 50% had a response lasting 24 months or longer.

The most common adverse events associated with pembrolizumab in this trial were fatigue, musculoskeletal pain, decreased appetite, pruritus, diarrhea, nausea, rash, pyrexia, cough, dyspnea, constipation, pain, and abdominal pain. Pembrolizumab is associated with immune-mediated side effects, including pneumonitis, colitis, hepatitis, endocrinopathies, nephritis, and skin adverse reactions, the FDA noted.

Safety and efficacy of pembrolizumab in pediatric patients with TMB-H central nervous system cancers have not been established.
 

New option for recurrent or metastatic cSCC

Physicians treating patients with cSCC that is not curable by surgery or radiation now have pembrolizumab to consider as another treatment option.

The cSCC approval is based on results of the multicenter, open-label KEYNOTE-629 trial. The dosage regimen was 200 mg of pembrolizumab intravenously every 3 weeks until cancer progressed, unacceptable toxicity arose, or 24 months of treatment were completed.

The objective response rate was 34%, and the median duration of response was not reached.

Adverse events were similar to those occurring in patients who received pembrolizumab as a single agent in other clinical trials, the FDA noted.

The Food and Drug Administration recently announced two new types of cancer that can be treated by the anti–PD-1 antibody pembrolizumab.

The new indications expand the use of pembrolizumab (Keytruda) to include treatment of patients with unresectable or metastatic tumor mutational burden–high (TMB-H) solid tumors as well as patients with cutaneous squamous cell carcinoma (cSCC). The FDA announced the new indications just 8 days apart, on June 16 and June 24.

In addition, on June 29, the FDA approved a third new indication for pembrolizumab, this time as first-line treatment for patients with unresectable or metastatic microsatellite instability–high or mismatch repair–deficient colorectal cancer.



The new approvals add to a wide range of oncology indications for which pembrolizumab can be used.

Accelerated approval to treat solid tumors

The FDA granted accelerated approval for pembrolizumab to treat children and adults with unresectable or metastatic TMB-H solid tumors that progressed after previous treatment or in instances where there are no satisfactory alternative treatment options.

The tumor mutational burden must be confirmed by an FDA-approved test. To that end, the FDA approved the FoundationOneCDx assay, which is designed to help physicians determine which patients meet the threshold for TMB-H malignancies (10 or more mutations per megabase).

The efficacy of pembrolizumab in TMB-H solid tumors was investigated in 10 cohorts from the multicenter, open-label KEYNOTE-158 trial. Participants received 200 mg of pembrolizumab intravenously every 3 weeks until their disease progressed or they experienced unacceptable toxicity.

Within this population, 102 patients had tumors that met the TMB-H definition. In this group, the overall response rate was 29%, including a 25% partial response rate and a 4% complete response rate.

The median duration of response was not reached, but 57% of participants experienced a response lasting 12 months or longer, and 50% had a response lasting 24 months or longer.

The most common adverse events associated with pembrolizumab in this trial were fatigue, musculoskeletal pain, decreased appetite, pruritus, diarrhea, nausea, rash, pyrexia, cough, dyspnea, constipation, pain, and abdominal pain. Pembrolizumab is associated with immune-mediated side effects, including pneumonitis, colitis, hepatitis, endocrinopathies, nephritis, and skin adverse reactions, the FDA noted.

Safety and efficacy of pembrolizumab in pediatric patients with TMB-H central nervous system cancers have not been established.
 

New option for recurrent or metastatic cSCC

Physicians treating patients with cSCC that is not curable by surgery or radiation now have pembrolizumab to consider as another treatment option.

The cSCC approval is based on results of the multicenter, open-label KEYNOTE-629 trial. The dosage regimen was 200 mg of pembrolizumab intravenously every 3 weeks until cancer progressed, unacceptable toxicity arose, or 24 months of treatment were completed.

The objective response rate was 34%, and the median duration of response was not reached.

Adverse events were similar to those occurring in patients who received pembrolizumab as a single agent in other clinical trials, the FDA noted.

The oral selective estrogen receptor degrader (SERD) LSZ102 plus either ribociclib or alpelisib shows manageable safety and encouraging clinical activity in heavily pretreated estrogen receptor (ER)–positive breast cancer patients who progressed after prior endocrine therapy, according to interim results of an open-label phase 1/1b study.

The effects seen in the study, which is the first to report on an oral SERD in combination with both CDK4/6 and PI3Ka inhibitors, occurred regardless of ESR1 and PIK3CA mutations, said Komal Jhaveri, MD, of Memorial Sloan Kettering Cancer Center in New York.

Dr. Jhaveri reported the results at the European Society of Medical Oncology: Breast Cancer virtual meeting.

The overall response rate (ORR) among 78 patients enrolled in an LSZ102 monotherapy arm (arm A) was 1.3%, and the progression-free survival (PFS) was 1.8 months. The clinical benefit rate (CBR) was 9.1%.

Among 76 patients enrolled in an LSZ102+ribociclib arm (arm B), the ORR was 15.8%, the PFS was 6.2 months, and the CBR was 35.5%.

Among the 39 patients enrolled in an LSZ102+alpelisib arm (arm C), the ORR was 5.4%, the PFS was 3.5 months, and the CBR was 18.9%.

After the data cutoff, one additional partial response (PR) was reported in arm C, Dr. Jhaveri said, noting that two of three confirmed responses were in known PIKC3A-mutant patients.

Study participants were aged 18 years and older with a confirmed diagnosis of ER-positive breast cancer and good performance status, as well as evidence of progression after endocrine therapy for metastatic disease or evidence of progression while on therapy or within 12 months from the end of adjuvant therapy.

“For all arms, prior fulvestrant, CDK46 inhibitor, or chemotherapy were allowed. For arm C, patients with or without PIK3C were eligible, and no prior treatment with PIK3, mTOR, or AKT inhibitors was allowed,” Dr. Jhaveri said.

Dosing in the LSZ102 monotherapy arm ranged from 200 to 900 mg. Arm B patients received LSZ102 at doses of 200-600 mg and ribociclib at doses of 200-600 mg. Both continuous ribociclib and 3 weeks on/1 week off dosing were evaluated. Arm C patients received LSZ102 at doses of 300-450 mg and alpelisib at 200-300 mg.

The recommended expansion doses were 450 mg daily of LSZ102 for arm A and 450 mg LSZ102 with 400 mg of daily ribociclib for arm B. For arm C, they were 300 mg LSZ102 with 250 mg of alpelisib daily.

Of note, two of three patients with a PR in arm C had received 300 mg LSZ102 and 300 mg alpelisib, Dr. Jhaveri said.

Arm A and arm B results were presented at the San Antonio Breast Cancer Symposium in 2018 and 2019, respectively. The current report updates those findings and presents arm C data for the first time, Dr. Jhaveri said.

LSZ102 was relatively well-tolerated as a single agent and in combination with ribociclib and alpelisib, according to Dr. Jhaveri. The most frequent adverse events were gastrointestinal toxicities, including nausea, vomiting, diarrhea, and decreased appetite, which occurred across all arms.

Neutropenia and aspartate aminotransferase abnormalities, including grade 3 cases, were reported in arm B and were most likely driven by the ribociclib, Dr. Jhaveri said. Grade 3 hypoglycemia and skin rash commonly occurred in arm C, most likely driven by the alpelisib.

Five dose-limiting toxicities occurred in four patients in arm A, three occurred in two patients in arm B, and seven occurred in seven patients in arm C.

Paired biopsies collected at the time of screening and at day 15 of cycle 1 showed consistent down-regulation of ER protein levels across arms.

“No substantial dose-dependent down-regulation of the ER was observed with increasing doses of LSZ,” Dr. Jhaveri said.

Circulating tumor DNA (ctDNA) analysis showed that the dominant mutations across the arms were ESR1, PIK3CA, and TP53. These were not shown to correlate with response and were not enriched upon progression in patients with matched baseline and end-of-treatment samples, she noted.

An exploratory analysis, conducted in “a preliminary attempt to correlate clinical activity with specific mutations,” showed that, in arms B and C, respectively, ORR, CBR, and PFS weren’t correlated with the presence or absence of ESR1 and PIK3CA mutations, respectively, or the absence of detectable ctDNA from baseline samples, Dr. Jhaveri said.

“While numerically higher responses and better CBR were seen in patients with undetectable ctDNA at baseline, no statistically significant difference in any of these outcomes was observed in arms B and C,” she said.

In arm C, the numbers were small at the time of data cutoff, but incoming data suggest relatively enhanced activity of the LSZ102 plus alpelisib combination in PIKC3A-mutant patients, she noted.

“We know that inhibiting ER signaling is the mainstay of treatment for ER-positive breast cancer,” Dr. Jhaveri explained, adding that aromatase inhibitors, estrogen receptor modulators, and SERDs are important classes of antiestrogenic agents, but fulvestrant is the only approved SERD. These are effective, but many patients develop resistance, she said.

“Proposed mechanisms for endocrine resistance include activation of the cell-cycle and cell-survival signaling pathways, or of the PI3K-AKT-mTOR pathway,” Dr. Jhaveri said. “To that end, ribociclib, a CDK46 inhibitor plus fulvestrant improved survival compared to fulvestrant alone in patients with ER-positive metastatic breast cancer.”

More recently, the PI3K inhibitor alpelisib plus fulvestrant also nearly doubled PFS vs. fulvestrant alone in PIKC3A-mutant, ER-positive metastatic breast cancer, which led to the approval of the combination in the United States.

Another mechanism of endocrine resistance includes acquisition of activating mutations in the estrogen receptor gene itself that allow tumors to survive and proliferate without depending on estrogen.

EGFR mutations appear to predict resistance to aromatase inhibitor therapies, but not outcomes in patients treated with fulvestrant. However, fulvestrant, which is delivered by intramuscular injection, has its own limitations, Dr. Jhaveri said.

“LSZ102 is a novel SERD that could achieve higher exposure than fulvestrant, leading to enhanced efficacy,” she said, noting that it was shown in preclinical models to have activity and to be synergistic in combination with ribociclib and alpelisib, forming the basis for the current study.

Invited discussant, Saverio Cinieri, MD, of Ospedale Antonio Perrino, Brindisi, Italy, said the study “elegantly demonstrated that estrogen receptor protein is down-regulated by LSZ102; [that] the genomic landscape of heavily pretreated patients is dominated by mutations in ESR1, PIK3CA, and TP53; [that] common mutations do not correlate with response and are not enriched on progression; [and that] ctDNA analysis at baseline shows similar outcomes with LSZ plus ribociclib or alpelisib, regardless of mutational status.”

LSZ102 is one of four new-generation SERDs in early-phase studies, he said, concluding that “in the COVID-19 era, the use of oral therapies will be even more necessary to limit access to the hospital.”

Dr. Cinieri also said that overcoming the limitations “of a molecule like the intramuscularly administered fulvestrant goes in this direction,” and that “the clinical efficacy and the biomolecular profile of LSZ102 seems to be able to meet these real needs.”

This study was funded by Novartis. Dr. Jhaveri reported advisory and consultancy roles and/or research grants or other funding to her institution from Novartis, ADC Therapeutics, Pfizer, and numerous other pharmaceutical and biotechnology companies. Dr. Cinieri reported relationships with Lily Oncology, Pfizer, Roche, AstraZeneca, Amgen, Novartis, including honoraria, grant and research support to his institution, advisory board participation, and scientific meeting support.

[email protected]

SOURCE: Jhaveri K et al. ESMO Breast Cancer, Abstract LBA1.

The oral selective estrogen receptor degrader (SERD) LSZ102 plus either ribociclib or alpelisib shows manageable safety and encouraging clinical activity in heavily pretreated estrogen receptor (ER)–positive breast cancer patients who progressed after prior endocrine therapy, according to interim results of an open-label phase 1/1b study.

The effects seen in the study, which is the first to report on an oral SERD in combination with both CDK4/6 and PI3Ka inhibitors, occurred regardless of ESR1 and PIK3CA mutations, said Komal Jhaveri, MD, of Memorial Sloan Kettering Cancer Center in New York.

Dr. Jhaveri reported the results at the European Society of Medical Oncology: Breast Cancer virtual meeting.

The overall response rate (ORR) among 78 patients enrolled in an LSZ102 monotherapy arm (arm A) was 1.3%, and the progression-free survival (PFS) was 1.8 months. The clinical benefit rate (CBR) was 9.1%.

Among 76 patients enrolled in an LSZ102+ribociclib arm (arm B), the ORR was 15.8%, the PFS was 6.2 months, and the CBR was 35.5%.

Among the 39 patients enrolled in an LSZ102+alpelisib arm (arm C), the ORR was 5.4%, the PFS was 3.5 months, and the CBR was 18.9%.

After the data cutoff, one additional partial response (PR) was reported in arm C, Dr. Jhaveri said, noting that two of three confirmed responses were in known PIKC3A-mutant patients.

Study participants were aged 18 years and older with a confirmed diagnosis of ER-positive breast cancer and good performance status, as well as evidence of progression after endocrine therapy for metastatic disease or evidence of progression while on therapy or within 12 months from the end of adjuvant therapy.

“For all arms, prior fulvestrant, CDK46 inhibitor, or chemotherapy were allowed. For arm C, patients with or without PIK3C were eligible, and no prior treatment with PIK3, mTOR, or AKT inhibitors was allowed,” Dr. Jhaveri said.

Dosing in the LSZ102 monotherapy arm ranged from 200 to 900 mg. Arm B patients received LSZ102 at doses of 200-600 mg and ribociclib at doses of 200-600 mg. Both continuous ribociclib and 3 weeks on/1 week off dosing were evaluated. Arm C patients received LSZ102 at doses of 300-450 mg and alpelisib at 200-300 mg.

The recommended expansion doses were 450 mg daily of LSZ102 for arm A and 450 mg LSZ102 with 400 mg of daily ribociclib for arm B. For arm C, they were 300 mg LSZ102 with 250 mg of alpelisib daily.

Of note, two of three patients with a PR in arm C had received 300 mg LSZ102 and 300 mg alpelisib, Dr. Jhaveri said.

Arm A and arm B results were presented at the San Antonio Breast Cancer Symposium in 2018 and 2019, respectively. The current report updates those findings and presents arm C data for the first time, Dr. Jhaveri said.

LSZ102 was relatively well-tolerated as a single agent and in combination with ribociclib and alpelisib, according to Dr. Jhaveri. The most frequent adverse events were gastrointestinal toxicities, including nausea, vomiting, diarrhea, and decreased appetite, which occurred across all arms.

Neutropenia and aspartate aminotransferase abnormalities, including grade 3 cases, were reported in arm B and were most likely driven by the ribociclib, Dr. Jhaveri said. Grade 3 hypoglycemia and skin rash commonly occurred in arm C, most likely driven by the alpelisib.

Five dose-limiting toxicities occurred in four patients in arm A, three occurred in two patients in arm B, and seven occurred in seven patients in arm C.

Paired biopsies collected at the time of screening and at day 15 of cycle 1 showed consistent down-regulation of ER protein levels across arms.

“No substantial dose-dependent down-regulation of the ER was observed with increasing doses of LSZ,” Dr. Jhaveri said.

Circulating tumor DNA (ctDNA) analysis showed that the dominant mutations across the arms were ESR1, PIK3CA, and TP53. These were not shown to correlate with response and were not enriched upon progression in patients with matched baseline and end-of-treatment samples, she noted.

An exploratory analysis, conducted in “a preliminary attempt to correlate clinical activity with specific mutations,” showed that, in arms B and C, respectively, ORR, CBR, and PFS weren’t correlated with the presence or absence of ESR1 and PIK3CA mutations, respectively, or the absence of detectable ctDNA from baseline samples, Dr. Jhaveri said.

“While numerically higher responses and better CBR were seen in patients with undetectable ctDNA at baseline, no statistically significant difference in any of these outcomes was observed in arms B and C,” she said.

In arm C, the numbers were small at the time of data cutoff, but incoming data suggest relatively enhanced activity of the LSZ102 plus alpelisib combination in PIKC3A-mutant patients, she noted.

“We know that inhibiting ER signaling is the mainstay of treatment for ER-positive breast cancer,” Dr. Jhaveri explained, adding that aromatase inhibitors, estrogen receptor modulators, and SERDs are important classes of antiestrogenic agents, but fulvestrant is the only approved SERD. These are effective, but many patients develop resistance, she said.

“Proposed mechanisms for endocrine resistance include activation of the cell-cycle and cell-survival signaling pathways, or of the PI3K-AKT-mTOR pathway,” Dr. Jhaveri said. “To that end, ribociclib, a CDK46 inhibitor plus fulvestrant improved survival compared to fulvestrant alone in patients with ER-positive metastatic breast cancer.”

More recently, the PI3K inhibitor alpelisib plus fulvestrant also nearly doubled PFS vs. fulvestrant alone in PIKC3A-mutant, ER-positive metastatic breast cancer, which led to the approval of the combination in the United States.

Another mechanism of endocrine resistance includes acquisition of activating mutations in the estrogen receptor gene itself that allow tumors to survive and proliferate without depending on estrogen.

EGFR mutations appear to predict resistance to aromatase inhibitor therapies, but not outcomes in patients treated with fulvestrant. However, fulvestrant, which is delivered by intramuscular injection, has its own limitations, Dr. Jhaveri said.

“LSZ102 is a novel SERD that could achieve higher exposure than fulvestrant, leading to enhanced efficacy,” she said, noting that it was shown in preclinical models to have activity and to be synergistic in combination with ribociclib and alpelisib, forming the basis for the current study.

Invited discussant, Saverio Cinieri, MD, of Ospedale Antonio Perrino, Brindisi, Italy, said the study “elegantly demonstrated that estrogen receptor protein is down-regulated by LSZ102; [that] the genomic landscape of heavily pretreated patients is dominated by mutations in ESR1, PIK3CA, and TP53; [that] common mutations do not correlate with response and are not enriched on progression; [and that] ctDNA analysis at baseline shows similar outcomes with LSZ plus ribociclib or alpelisib, regardless of mutational status.”

LSZ102 is one of four new-generation SERDs in early-phase studies, he said, concluding that “in the COVID-19 era, the use of oral therapies will be even more necessary to limit access to the hospital.”

Dr. Cinieri also said that overcoming the limitations “of a molecule like the intramuscularly administered fulvestrant goes in this direction,” and that “the clinical efficacy and the biomolecular profile of LSZ102 seems to be able to meet these real needs.”

This study was funded by Novartis. Dr. Jhaveri reported advisory and consultancy roles and/or research grants or other funding to her institution from Novartis, ADC Therapeutics, Pfizer, and numerous other pharmaceutical and biotechnology companies. Dr. Cinieri reported relationships with Lily Oncology, Pfizer, Roche, AstraZeneca, Amgen, Novartis, including honoraria, grant and research support to his institution, advisory board participation, and scientific meeting support.

[email protected]

SOURCE: Jhaveri K et al. ESMO Breast Cancer, Abstract LBA1.

The oral selective estrogen receptor degrader (SERD) LSZ102 plus either ribociclib or alpelisib shows manageable safety and encouraging clinical activity in heavily pretreated estrogen receptor (ER)–positive breast cancer patients who progressed after prior endocrine therapy, according to interim results of an open-label phase 1/1b study.

The effects seen in the study, which is the first to report on an oral SERD in combination with both CDK4/6 and PI3Ka inhibitors, occurred regardless of ESR1 and PIK3CA mutations, said Komal Jhaveri, MD, of Memorial Sloan Kettering Cancer Center in New York.

Dr. Jhaveri reported the results at the European Society of Medical Oncology: Breast Cancer virtual meeting.

The overall response rate (ORR) among 78 patients enrolled in an LSZ102 monotherapy arm (arm A) was 1.3%, and the progression-free survival (PFS) was 1.8 months. The clinical benefit rate (CBR) was 9.1%.

Among 76 patients enrolled in an LSZ102+ribociclib arm (arm B), the ORR was 15.8%, the PFS was 6.2 months, and the CBR was 35.5%.

Among the 39 patients enrolled in an LSZ102+alpelisib arm (arm C), the ORR was 5.4%, the PFS was 3.5 months, and the CBR was 18.9%.

After the data cutoff, one additional partial response (PR) was reported in arm C, Dr. Jhaveri said, noting that two of three confirmed responses were in known PIKC3A-mutant patients.

Study participants were aged 18 years and older with a confirmed diagnosis of ER-positive breast cancer and good performance status, as well as evidence of progression after endocrine therapy for metastatic disease or evidence of progression while on therapy or within 12 months from the end of adjuvant therapy.

“For all arms, prior fulvestrant, CDK46 inhibitor, or chemotherapy were allowed. For arm C, patients with or without PIK3C were eligible, and no prior treatment with PIK3, mTOR, or AKT inhibitors was allowed,” Dr. Jhaveri said.

Dosing in the LSZ102 monotherapy arm ranged from 200 to 900 mg. Arm B patients received LSZ102 at doses of 200-600 mg and ribociclib at doses of 200-600 mg. Both continuous ribociclib and 3 weeks on/1 week off dosing were evaluated. Arm C patients received LSZ102 at doses of 300-450 mg and alpelisib at 200-300 mg.

The recommended expansion doses were 450 mg daily of LSZ102 for arm A and 450 mg LSZ102 with 400 mg of daily ribociclib for arm B. For arm C, they were 300 mg LSZ102 with 250 mg of alpelisib daily.

Of note, two of three patients with a PR in arm C had received 300 mg LSZ102 and 300 mg alpelisib, Dr. Jhaveri said.

Arm A and arm B results were presented at the San Antonio Breast Cancer Symposium in 2018 and 2019, respectively. The current report updates those findings and presents arm C data for the first time, Dr. Jhaveri said.

LSZ102 was relatively well-tolerated as a single agent and in combination with ribociclib and alpelisib, according to Dr. Jhaveri. The most frequent adverse events were gastrointestinal toxicities, including nausea, vomiting, diarrhea, and decreased appetite, which occurred across all arms.

Neutropenia and aspartate aminotransferase abnormalities, including grade 3 cases, were reported in arm B and were most likely driven by the ribociclib, Dr. Jhaveri said. Grade 3 hypoglycemia and skin rash commonly occurred in arm C, most likely driven by the alpelisib.

Five dose-limiting toxicities occurred in four patients in arm A, three occurred in two patients in arm B, and seven occurred in seven patients in arm C.

Paired biopsies collected at the time of screening and at day 15 of cycle 1 showed consistent down-regulation of ER protein levels across arms.

“No substantial dose-dependent down-regulation of the ER was observed with increasing doses of LSZ,” Dr. Jhaveri said.

Circulating tumor DNA (ctDNA) analysis showed that the dominant mutations across the arms were ESR1, PIK3CA, and TP53. These were not shown to correlate with response and were not enriched upon progression in patients with matched baseline and end-of-treatment samples, she noted.

An exploratory analysis, conducted in “a preliminary attempt to correlate clinical activity with specific mutations,” showed that, in arms B and C, respectively, ORR, CBR, and PFS weren’t correlated with the presence or absence of ESR1 and PIK3CA mutations, respectively, or the absence of detectable ctDNA from baseline samples, Dr. Jhaveri said.

“While numerically higher responses and better CBR were seen in patients with undetectable ctDNA at baseline, no statistically significant difference in any of these outcomes was observed in arms B and C,” she said.

In arm C, the numbers were small at the time of data cutoff, but incoming data suggest relatively enhanced activity of the LSZ102 plus alpelisib combination in PIKC3A-mutant patients, she noted.

“We know that inhibiting ER signaling is the mainstay of treatment for ER-positive breast cancer,” Dr. Jhaveri explained, adding that aromatase inhibitors, estrogen receptor modulators, and SERDs are important classes of antiestrogenic agents, but fulvestrant is the only approved SERD. These are effective, but many patients develop resistance, she said.

“Proposed mechanisms for endocrine resistance include activation of the cell-cycle and cell-survival signaling pathways, or of the PI3K-AKT-mTOR pathway,” Dr. Jhaveri said. “To that end, ribociclib, a CDK46 inhibitor plus fulvestrant improved survival compared to fulvestrant alone in patients with ER-positive metastatic breast cancer.”

More recently, the PI3K inhibitor alpelisib plus fulvestrant also nearly doubled PFS vs. fulvestrant alone in PIKC3A-mutant, ER-positive metastatic breast cancer, which led to the approval of the combination in the United States.

Another mechanism of endocrine resistance includes acquisition of activating mutations in the estrogen receptor gene itself that allow tumors to survive and proliferate without depending on estrogen.

EGFR mutations appear to predict resistance to aromatase inhibitor therapies, but not outcomes in patients treated with fulvestrant. However, fulvestrant, which is delivered by intramuscular injection, has its own limitations, Dr. Jhaveri said.

“LSZ102 is a novel SERD that could achieve higher exposure than fulvestrant, leading to enhanced efficacy,” she said, noting that it was shown in preclinical models to have activity and to be synergistic in combination with ribociclib and alpelisib, forming the basis for the current study.

Invited discussant, Saverio Cinieri, MD, of Ospedale Antonio Perrino, Brindisi, Italy, said the study “elegantly demonstrated that estrogen receptor protein is down-regulated by LSZ102; [that] the genomic landscape of heavily pretreated patients is dominated by mutations in ESR1, PIK3CA, and TP53; [that] common mutations do not correlate with response and are not enriched on progression; [and that] ctDNA analysis at baseline shows similar outcomes with LSZ plus ribociclib or alpelisib, regardless of mutational status.”

LSZ102 is one of four new-generation SERDs in early-phase studies, he said, concluding that “in the COVID-19 era, the use of oral therapies will be even more necessary to limit access to the hospital.”

Dr. Cinieri also said that overcoming the limitations “of a molecule like the intramuscularly administered fulvestrant goes in this direction,” and that “the clinical efficacy and the biomolecular profile of LSZ102 seems to be able to meet these real needs.”

This study was funded by Novartis. Dr. Jhaveri reported advisory and consultancy roles and/or research grants or other funding to her institution from Novartis, ADC Therapeutics, Pfizer, and numerous other pharmaceutical and biotechnology companies. Dr. Cinieri reported relationships with Lily Oncology, Pfizer, Roche, AstraZeneca, Amgen, Novartis, including honoraria, grant and research support to his institution, advisory board participation, and scientific meeting support.

[email protected]

SOURCE: Jhaveri K et al. ESMO Breast Cancer, Abstract LBA1.

The Food and Drug Administration approved a combination of pertuzumab (Perjeta, Genentech/Roche), trastuzumab (Herceptin, Genentech/Roche) and hyaluronidase (Phesgo, Genentech/Roche) that is administered subcutaneously – rather than intravenously – for the treatment of early and metastatic HER2-positive breast cancers.

Phesgo is initially used in combination with chemotherapy at an infusion center but could continue to be administered in a patient’s home by a qualified health care professional once chemotherapy is complete, according to the FDA.

Administration takes approximately 8 minutes for the initial loading dose and approximately 5 minutes for maintenance doses, according to a Genentech press statement. This compares favorably with the 150 minutes needed for the combined loading dose of intravenous pertuzumab and trastuzumab, and the 60-150 minutes for intravenous maintenance infusions, the company said.

“Currently, most patients with HER2-positive breast cancer receive trastuzumab and pertuzumab at infusion centers. With a new administration route, Phesgo offers an outpatient option for patients to receive trastuzumab and pertuzumab,” said Richard Pazdur, MD, director of the FDA’s Oncology Center of Excellence and acting director of the Office of Oncologic Diseases in the FDA’s Center for Drug Evaluation and Research, in an agency press release.

“The fixed-dose combination of trastuzumab and pertuzumab offers a simpler, faster, and easier treatment experience for patients with HER2-positive breast cancer,” said Antoinette Tan, MD, MHSc, chief of breast medical oncology at Levine Cancer Institute, Charlotte, N.C., in the company statement.

Dr. Tan also said that home administration “can be advantageous for patients and infusion centers.”

However, in April, the Community Oncology Alliance strenuously objected to this type of treatment in a patient’s home, as reported by Medscape Medical News.

The group, which represents U.S. community-based practices, said it “fundamentally opposes home infusion of chemotherapy, cancer immunotherapy, and cancer treatment supportive drugs because of serious patient safety concerns.”

The FDA’s approval was based on the results of the pivotal phase 3 FeDeriCa trial, a noninferiority study in patients with HER2-positive early breast cancer, which demonstrated that the new product had comparable efficacy and safety as intravenous pertuzumab and intravenous trastuzumab.

In terms of efficacy, the subcutaneous product demonstrated noninferior plasma levels of pertuzumab, which was the primary endpoint, when compared with IV administration of pertuzumab.

Safety was comparable between the two approaches, with no new safety signals using the subcutaneous delivery method, including no “meaningful difference” in cardiac toxicity, according to Genentech. However, there were more administration-related reactions with the new product. The most common adverse events in both groups were alopecia, nausea, diarrhea, and anemia.

The new product uses a drug delivery technology (Enhanze, Halozyme Therapeutics) that employs a proprietary enzyme that temporarily degrades hyaluronan, a glycosaminoglycan or chain of natural sugars in the body, to facilitate the dispersion and absorption of injected therapeutic drugs, according to Genentech.

In May, at the European Society for Medical Oncology Breast Cancer Virtual Meeting 2020, investigators of the phase 2 PHranceSCa study reported that “more than 80%” of patients preferred subcutaneous to intravenous administration of pertuzumab and trastuzumab.

This article first appeared on Medscape.com.

The Food and Drug Administration approved a combination of pertuzumab (Perjeta, Genentech/Roche), trastuzumab (Herceptin, Genentech/Roche) and hyaluronidase (Phesgo, Genentech/Roche) that is administered subcutaneously – rather than intravenously – for the treatment of early and metastatic HER2-positive breast cancers.

Phesgo is initially used in combination with chemotherapy at an infusion center but could continue to be administered in a patient’s home by a qualified health care professional once chemotherapy is complete, according to the FDA.

Administration takes approximately 8 minutes for the initial loading dose and approximately 5 minutes for maintenance doses, according to a Genentech press statement. This compares favorably with the 150 minutes needed for the combined loading dose of intravenous pertuzumab and trastuzumab, and the 60-150 minutes for intravenous maintenance infusions, the company said.

“Currently, most patients with HER2-positive breast cancer receive trastuzumab and pertuzumab at infusion centers. With a new administration route, Phesgo offers an outpatient option for patients to receive trastuzumab and pertuzumab,” said Richard Pazdur, MD, director of the FDA’s Oncology Center of Excellence and acting director of the Office of Oncologic Diseases in the FDA’s Center for Drug Evaluation and Research, in an agency press release.

“The fixed-dose combination of trastuzumab and pertuzumab offers a simpler, faster, and easier treatment experience for patients with HER2-positive breast cancer,” said Antoinette Tan, MD, MHSc, chief of breast medical oncology at Levine Cancer Institute, Charlotte, N.C., in the company statement.

Dr. Tan also said that home administration “can be advantageous for patients and infusion centers.”

However, in April, the Community Oncology Alliance strenuously objected to this type of treatment in a patient’s home, as reported by Medscape Medical News.

The group, which represents U.S. community-based practices, said it “fundamentally opposes home infusion of chemotherapy, cancer immunotherapy, and cancer treatment supportive drugs because of serious patient safety concerns.”

The FDA’s approval was based on the results of the pivotal phase 3 FeDeriCa trial, a noninferiority study in patients with HER2-positive early breast cancer, which demonstrated that the new product had comparable efficacy and safety as intravenous pertuzumab and intravenous trastuzumab.

In terms of efficacy, the subcutaneous product demonstrated noninferior plasma levels of pertuzumab, which was the primary endpoint, when compared with IV administration of pertuzumab.

Safety was comparable between the two approaches, with no new safety signals using the subcutaneous delivery method, including no “meaningful difference” in cardiac toxicity, according to Genentech. However, there were more administration-related reactions with the new product. The most common adverse events in both groups were alopecia, nausea, diarrhea, and anemia.

The new product uses a drug delivery technology (Enhanze, Halozyme Therapeutics) that employs a proprietary enzyme that temporarily degrades hyaluronan, a glycosaminoglycan or chain of natural sugars in the body, to facilitate the dispersion and absorption of injected therapeutic drugs, according to Genentech.

In May, at the European Society for Medical Oncology Breast Cancer Virtual Meeting 2020, investigators of the phase 2 PHranceSCa study reported that “more than 80%” of patients preferred subcutaneous to intravenous administration of pertuzumab and trastuzumab.

This article first appeared on Medscape.com.

The Food and Drug Administration approved a combination of pertuzumab (Perjeta, Genentech/Roche), trastuzumab (Herceptin, Genentech/Roche) and hyaluronidase (Phesgo, Genentech/Roche) that is administered subcutaneously – rather than intravenously – for the treatment of early and metastatic HER2-positive breast cancers.

Phesgo is initially used in combination with chemotherapy at an infusion center but could continue to be administered in a patient’s home by a qualified health care professional once chemotherapy is complete, according to the FDA.

Administration takes approximately 8 minutes for the initial loading dose and approximately 5 minutes for maintenance doses, according to a Genentech press statement. This compares favorably with the 150 minutes needed for the combined loading dose of intravenous pertuzumab and trastuzumab, and the 60-150 minutes for intravenous maintenance infusions, the company said.

“Currently, most patients with HER2-positive breast cancer receive trastuzumab and pertuzumab at infusion centers. With a new administration route, Phesgo offers an outpatient option for patients to receive trastuzumab and pertuzumab,” said Richard Pazdur, MD, director of the FDA’s Oncology Center of Excellence and acting director of the Office of Oncologic Diseases in the FDA’s Center for Drug Evaluation and Research, in an agency press release.

“The fixed-dose combination of trastuzumab and pertuzumab offers a simpler, faster, and easier treatment experience for patients with HER2-positive breast cancer,” said Antoinette Tan, MD, MHSc, chief of breast medical oncology at Levine Cancer Institute, Charlotte, N.C., in the company statement.

Dr. Tan also said that home administration “can be advantageous for patients and infusion centers.”

However, in April, the Community Oncology Alliance strenuously objected to this type of treatment in a patient’s home, as reported by Medscape Medical News.

The group, which represents U.S. community-based practices, said it “fundamentally opposes home infusion of chemotherapy, cancer immunotherapy, and cancer treatment supportive drugs because of serious patient safety concerns.”

The FDA’s approval was based on the results of the pivotal phase 3 FeDeriCa trial, a noninferiority study in patients with HER2-positive early breast cancer, which demonstrated that the new product had comparable efficacy and safety as intravenous pertuzumab and intravenous trastuzumab.

In terms of efficacy, the subcutaneous product demonstrated noninferior plasma levels of pertuzumab, which was the primary endpoint, when compared with IV administration of pertuzumab.

Safety was comparable between the two approaches, with no new safety signals using the subcutaneous delivery method, including no “meaningful difference” in cardiac toxicity, according to Genentech. However, there were more administration-related reactions with the new product. The most common adverse events in both groups were alopecia, nausea, diarrhea, and anemia.

The new product uses a drug delivery technology (Enhanze, Halozyme Therapeutics) that employs a proprietary enzyme that temporarily degrades hyaluronan, a glycosaminoglycan or chain of natural sugars in the body, to facilitate the dispersion and absorption of injected therapeutic drugs, according to Genentech.

In May, at the European Society for Medical Oncology Breast Cancer Virtual Meeting 2020, investigators of the phase 2 PHranceSCa study reported that “more than 80%” of patients preferred subcutaneous to intravenous administration of pertuzumab and trastuzumab.

This article first appeared on Medscape.com.

Key findings in metastatic breast cancer, presented at the ASCO 2020 Virtual Annual Meeting, ranged across all tumor subtypes.

Arguably, the top news in breast cancer was a plenary presentation addressing the role of locoregional therapy in advanced disease. Dr. Harold Burstein, of Dana-Farber Cancer Institute, comments that this study indicates systemic therapy as the mainstay treatment for woman with newly diagnosed advanced disease and a tumor in the breast.

In triple-negative breast cancer, Dr. Burstein highlights two studies. The KEYNOTE-355 study validates the addition of a checkpoint inhibitor in first-line therapy in women whose tumors are PD-L1 positive. The intriguing results of the SWOG S1416 trial, Dr. Burstein comments, suggest the use of PARP inhibition may extend beyond BRCA1 and BRCA2 breast cancers.

In HER2-positive breast cancer, an update of the HER2CLIMB study indicates that the combination of tucatinib, trastuzumab, and capecitabine continues to benefit women with HER2-positive disease. Dr. Burstein expects this combination will be a new standard of care, particularly in women with brain metastases.

As for ER-positive breast cancer, Dr. Burstein reviews the BYLieve trial. Results of this study suggest alpelisib has activity in women with a PIK3CA mutation who have already received a CDK4/6 inhibitor.

Harold J. Burstein, Md, PhD

Professor, Department of Medicine, Harvard Medical School; Institute Physician, Dana-Farber Cancer Institute, Boston, Massachusetts. Harold J. Burstein, MD, PhD, has disclosed no relevant financial relationships.

Key findings in metastatic breast cancer, presented at the ASCO 2020 Virtual Annual Meeting, ranged across all tumor subtypes.

Arguably, the top news in breast cancer was a plenary presentation addressing the role of locoregional therapy in advanced disease. Dr. Harold Burstein, of Dana-Farber Cancer Institute, comments that this study indicates systemic therapy as the mainstay treatment for woman with newly diagnosed advanced disease and a tumor in the breast.

In triple-negative breast cancer, Dr. Burstein highlights two studies. The KEYNOTE-355 study validates the addition of a checkpoint inhibitor in first-line therapy in women whose tumors are PD-L1 positive. The intriguing results of the SWOG S1416 trial, Dr. Burstein comments, suggest the use of PARP inhibition may extend beyond BRCA1 and BRCA2 breast cancers.

In HER2-positive breast cancer, an update of the HER2CLIMB study indicates that the combination of tucatinib, trastuzumab, and capecitabine continues to benefit women with HER2-positive disease. Dr. Burstein expects this combination will be a new standard of care, particularly in women with brain metastases.

As for ER-positive breast cancer, Dr. Burstein reviews the BYLieve trial. Results of this study suggest alpelisib has activity in women with a PIK3CA mutation who have already received a CDK4/6 inhibitor.

Harold J. Burstein, Md, PhD

Professor, Department of Medicine, Harvard Medical School; Institute Physician, Dana-Farber Cancer Institute, Boston, Massachusetts. Harold J. Burstein, MD, PhD, has disclosed no relevant financial relationships.

Key findings in metastatic breast cancer, presented at the ASCO 2020 Virtual Annual Meeting, ranged across all tumor subtypes.

Arguably, the top news in breast cancer was a plenary presentation addressing the role of locoregional therapy in advanced disease. Dr. Harold Burstein, of Dana-Farber Cancer Institute, comments that this study indicates systemic therapy as the mainstay treatment for woman with newly diagnosed advanced disease and a tumor in the breast.

In triple-negative breast cancer, Dr. Burstein highlights two studies. The KEYNOTE-355 study validates the addition of a checkpoint inhibitor in first-line therapy in women whose tumors are PD-L1 positive. The intriguing results of the SWOG S1416 trial, Dr. Burstein comments, suggest the use of PARP inhibition may extend beyond BRCA1 and BRCA2 breast cancers.

In HER2-positive breast cancer, an update of the HER2CLIMB study indicates that the combination of tucatinib, trastuzumab, and capecitabine continues to benefit women with HER2-positive disease. Dr. Burstein expects this combination will be a new standard of care, particularly in women with brain metastases.

As for ER-positive breast cancer, Dr. Burstein reviews the BYLieve trial. Results of this study suggest alpelisib has activity in women with a PIK3CA mutation who have already received a CDK4/6 inhibitor.

Harold J. Burstein, Md, PhD

Professor, Department of Medicine, Harvard Medical School; Institute Physician, Dana-Farber Cancer Institute, Boston, Massachusetts. Harold J. Burstein, MD, PhD, has disclosed no relevant financial relationships.

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.