Olaparib in the maintenance treatment of platinum-sensitive relapse of BRCA mutant ovarian cancer in routine clinical practice: first results of observational study in Russian patients

Background and aims. There is no data on olaparib efficacy and safety in Russian routine clinical practice. Methods. We analysed the 30 consecutive patients who received maintenance olaparib treatment for platinum-sensitive relapse (PSR) of ovarian or fallopian tube cancer in Russian Cancer Centers. Patients were prescribed olaparib capsules 400 mg twice daily. Radiographic assessments were done every 8 weeks. Patient characteristics. Age median 55 (range 39-68); 26 (86,6%) patients had gBRCA1, 2 (6,6%) patients had sBRCA1, 2 (6,6%) patients had gBRCA2. Number of relapse: median 1 (range 1-10), number of lines of chemotherapy: median 2 (range 2-11). Last regimen of chemotherapy: taxane + platinum (± bevacizumab) 90% (27/30), platinum monotherapy 10% (3/30). Best response to the last chemotherapy complete response 43,3% (13/30), partial response 36,7% (11/30), stable disease 20% (6/30). Results. Median follow-up in 13 CR patients was 12 mos. 1 CR patient progressed after 9 mos of maintenance olaparib. Median follow-up in 11 PR patients was 7 mos. 3 PR patients achieved CR on olaparib. 1 PR patient progressed after 6 mos of olaparib maintenance. Median follow-up in SD patients was 12 mos. 1 SD patient achieved PR on olaparib, there were no progressions. 10 (30%) patients had adverse events (AEs). 1 patient had grade 3 AE and 2 patients had AEs leading to dose reduction. There were no grade 4 AEs. Conclusions. Olaparib is safe and effective maintenance treatment of PSR ovarian cancer in routine clinical settings.