Olaparib monotherapy for Asian patients with a germline BRCA mutation and HER2-negative metastatic breast cancer:...

The OlympiAD Phase III study (NCT02000622) established the clinical benefits of olaparib tablet monotherapy (300 mg twice daily) over chemotherapy treatment of physician's choice (TPC) in patients with a germline BRCA1/2 mutation (gBRCAm) and human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer who had received ≤2 chemotherapy lines in the metastatic setting. Here, we report pre-specified analyses of data from Asian (China, Japan, Korea and Taiwan) patients in the study. All patients were randomized 2:1 to olaparib tablets (300 mg twice daily) or single-agent chemotherapy TPC (21-day cycles of either capecitabine, eribulin or vinorelbine). The primary endpoint was progression-free survival assessed by blinded independent central review. The prevalence of gBRCAm in the OlympiAD Asian subgroup screened for study recruitment was 13.5%. Patient demographics and disease characteristics of the Asian subgroup (87/302 patients) were generally well balanced between treatment arms. Asian patients in the olaparib arm achieved longer median progression-free survival, assessed by blinded independent central review, versus the chemotherapy TPC arm (5.7 vs 4.2 months; HR = 0.53 [95% CI: 0.29-0.97]), which was consistent with findings in the global OlympiAD study population. Findings on secondary efficacy and safety/tolerability outcome measures in Asian patients were also similar to those observed in the global OlympiAD study population. The OlympiAD study was not powered to detect race-related differences between treatment groups; however, the consistency of our findings with the global OlympiAD study population suggests that previously reported findings are generalizable to Asian patients.