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BACKGROUND: The authors performed a meta‐analysis to better quantify the benefit of maintenance poly(ADP‐ribose) polymerase inhibitor (PARPi) therapy to inform practice in platinum‐sensitive, recurrent, high‐grade ovarian cancer for patient subsets with the following characteristics: germline BRCA mutation (gBRCAm), somatic BRCA mutation (sBRCAm), wild‐type BRCA but homologous recombinant‐deficient (HRD), homologous recombinant‐proficient (HRP), and baseline clinical prognostic characteristics. METHODS: Randomized trials comparing a PARPi versus placebo as maintenance treatment were identified from electronic databases. Treatment estimates of progression‐free survival were pooled across trials using the inverse variance weighted method. RESULTS: Four trials included 972 patients who received a PARPi (olaparib, 31%; niraparib, 35%; or rucaparib, 34%) and 530 patients who received placebo. For patients who had germline BRCA1 mutation (gBRCAm1) (N = 471), the hazard ratio (HR) was 0.29 (95% CI, 0.23‐0.37); for those who had germline BRCA2 mutation (gBRCAm2) (N = 236), the HR was 0.26 (95% CI, 0.17‐0.39); and, for those who had sBRCAm (N = 123), the HR was 0.22 (95% CI, 0.12‐0.41). The treatment effect was similar between the gBRCAm and sBRCAm subsets (P =.48). In patients who had wild‐type BRCA HRD tumors (excluding sBRCAm; N = 309), the HR was 0.41 (95% CI, 0.31‐0.56); and, in those who had wild‐type BRCA HRP tumors (N = 346), the HR was 0.64 (95% CI, 0.49‐0.83). The relative treatment effect was greater for the BRCAm versus HRD (P =.03), BRCAm versus HRP (P <.00001), and HRD versus HRP (P <.00001) subsets. There was no difference in benefit based on age, response after recent chemotherapy, and prior bevacizumab. CONCLUSIONS: In platinum‐sensitive, recurrent, high‐grade ovarian cancer, maintenance PARPi improves progression‐free survival for all patient subsets. PARPi therapy has a similar magnitude of benefit for sBRCAm and gBRCAm. Although patients with BRCAm derive the greatest benefit, the absence of a BRCAm or HRD could not be used to exclude patients from maintenance PARPi therapy. BRCA mutation status is able to predict for the magnitude of PARP inhibitor benefit in platinum‐sensitive recurrent high‐grade ovarian tumor. However, the absence of a BRCA mutation or homologous recombinant deficiency in high‐grade ovarian tumor cannot be used to exclude patients from such therapy. [ABSTRACT FROM AUTHOR]

Ovarian cancer patients are usually diagnosed at an advanced stage, experience recurrence after platinum-based chemotherapy, and eventually develop resistance to chemotherapy. Overall survival (OS), which has improved in recent years as more active treatments have been incorporated into patient care, is regarded as the most clinically relevant endpoint in ovarian cancer trials. However, although there remains a significant need for new treatments that prolong OS further without compromising quality of life, it has become increasingly difficult to detect an OS benefit for investigational treatments because of the use of multiple lines of chemotherapy to treat ovarian cancer. Progression-free survival (PFS), which measures the time to disease progression or death, is unaffected by postprogression therapies but does not evaluate the long-term impact of investigational treatments on tumor biology and responses to future therapies. Recent clinical trials of targeted agents in relapsed ovarian cancer have shown improvements in PFS but not OS, and this is possibly reflective of the long postprogression survival (PPS) period associated with this disease. Intermediate endpoints such as the time to second disease progression or death and the time to second subsequent therapy or death may provide supportive evidence for clinically meaningful PFS improvements and may be used to determine whether these improvements persist beyond the first disease progression and throughout subsequent lines of therapy. For clinical trials that have settings with a long PPS duration and/or involve multiple rounds of postprogression therapy, a primary endpoint of PFS supported by intermediate clinical endpoints and OS may provide a more comprehensive approach for evaluating efficacy. Cancer 2015;121:1737-1746. © 2015 American Cancer Society. [ABSTRACT FROM AUTHOR]