Real-World Experience of Olaparib Maintenance in High-Grade Serous Recurrent Ovarian Cancer Patients with BRCA1/2 Mutation: A Korean Multicenter Study

Background: Olaparib maintenance therapy has shown efficacy and tolerability in patients with platinum-sensitive, high-grade serous recurrent ovarian cancer (HSROC) with BRCA1/2 mutation (BRCAm). Our aim was to present real-world experience with olaparib in Korea. Method: We included HSROC patients with BRCAm treated with olaparib maintenance at four institutions in Korea between 2016 and 2018. Medical records were reviewed for clinico-pathologic characteristics, objective response, survival outcomes, and safety. Results: One hundred HSROC patients with BRCAm were included. BRCA1 mutation was present in 71 patients (71.0%), and BRCA2 mutation was present in 23 patients (23.0%). In terms of the best objective response with olaparib maintenance in 53 patients with partial remission from most recent chemotherapy, complete remission occurred in 12 (22.6%) and partial remission in four (7.5%), while 33 patients (62.3%) had stable disease. The 24 month progression-free survival was 42.4%, and 24 month overall survival was 82.1%. Grade 3 or more adverse events were as follows: anemia in 14 patients (14.0%), neutropenia in seven patients (7.0%), thrombocytopenia in two patients (2.0%), oral mucositis in one patient (1.0%), and soft tissue infection in one patient (1.0%). Conclusions: The safety and effectiveness of olaparib maintenance treatment in a real-world study were consistent with those reported in previous clinical trials.