Olaparib is Efficacious in BRCA-related Metastatic Breast Cancer

The following article features coverage from the 2017 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago, Illinois. Click here to read more of Cancer Therapy Advisor‘s conference coverage.

Patients with a germline BRCA mutation were at a reduced risk for progression when treated with olaparib for HER2-metastatic breast cancer, according to a study presented at the 2017 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago.¹

Olaparib is a poly-ADP ribose polymerase (PARP) inhibitor approved for the treatment of ovarian cancer. OlympiAD was designed as a randomized, multinational, phase 3 study (ClinicalTrials.gov Identifier: NCT02000622) to determine if olaparib was better that standard chemotherapy for improving progression-free survival (PFS).

Mark E. Robson, MD, of the Memorial Sloan Kettering Cancer Center in New York, New York, presented the study. Patients assigned to the olaparib arm received olaparib 300 mg tablets twice daily. Patients in the chemotherapy arm received investigator’s choice of chemotherapy. Treatment was continued until disease progression or unacceptable toxicity.

Median patient age was 44 years; about 33% were non-Caucasian, 56% were positive for BRCA1 mutation and 43% for BRCA2 mutation; 1% had both. Seventy percent had triple-negative breast cancer, 71% received prior therapy for metastatic breast cancer.

Of 302 patients, 205 received olaparib and 91 received chemotherapy. Median follow up was 14 months. Median progression-free survival was 7 months for olaparib and 4.2 months for chemotherapy.

Olaparib was generally well-tolerated, with fewer grade 3 or greater side effects, fewer treatment discontinuations, and less myelosuppression.

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“This is the first phase 3 study to show advantage of a PARP inhibitor over standard of care chemotherapy in breast cancer patients with a BRCA mutation,” Dr Robson said.

Read more of Cancer Therapy Advisor‘s coverage of the 2017 American Society of Clinical Oncology (ASCO) Annual Meeting by visiting the conference page.

Reference

1. Robson ME, Im SA, Senkus E, et al. OlympiAD: Phase III trial of olaparib monotherapy versus chemotherapy for patients (pts) with HER2-negative metastatic breast cancer (mBC) and a germline BRCA mutation (gBRCAm). J Clin Oncol. 2017;34(suppl; abstr LBA4).