PARP Inhibitor in Platinum-Resistant Ovarian Cancer: Single-Center Real-World Experience

Abstract

PURPOSE Poly (ADP-ribose) polymerase inhibitors (PARPi) have proven efficacy in treatment of BReast CAncer (BRCA) gene mutation-positive platinum-sensitive ovarian cancers. There is paucity of data for their role in platinum-resistant ovarian cancer (PROC). We report here retrospective analysis of outcome of PARPi treatment in a group of patients including those of PROC. PATIENTS AND METHODS We analyzed all consecutive patients who received PARPi. The efficacy of PARPi monotherapy was assessed in patients with relapsed high-grade serous ovarian carcinoma with gBRCAm. The drug was procured through compassionate program. Drugs (olaparib and talazoparib) were provided in capsule form. RESULTS Between July 1, 2015, and June 30, 2019, 28 patients with ovarian cancer received PARPi. At the time of data censoring (September 30, 2019), four (14.3%) patients are still on treatment. Median age was 54.5 years (range, 39-75 years). Median number of previous lines of chemotherapy received was three (range, 1-6). Eleven platinum-sensitive patients received the drug as maintenance (five in complete response and six in partial response after chemotherapy), whereas 17 (60.7%) had platinum-resistant progressive disease while starting the drug. In PROC, objective response rate (complete response plus partial response) was 47%, median progression-free survival was 8.2 months (5.3-11.3), and overall survival was 14.9 months (11.2-18.5). No new side effects were observed. CONCLUSION This is the first study from India evaluating PARPi in platinum-resistant ovarian cancer. This study suggests that PARPi is a viable treatment option in patients with PROC with gBRCAm. This should be further evaluated in randomized clinical trial.