Olaparib as maintenance therapy in patients with BRCA 1–2 mutated recurrent platinum sensitive ovarian cancer: Real world data and post progression outcome
Olaparib is approved as maintenance therapy in patients with BRCA mutated platinum sensitive (PS) recurrent ovarian cancer (OC) after response to last platinum based therapy. Few data are available regarding the use out of the registration trials and on response to further treatments after progression. In this non interventional, retrospective study, patients treated with olaparib in 13 centers, according to the label, have been collected and analyzed. Primary objectives of the study are to describe effectiveness and safety of olaparib in a real world setting with a focus on post progression treatments and response. 234 patients were analyzed. All patients were BRCA mutated and most of them had germline mutations. Around 50% of the patients received olaparib after 3 or more lines of platinum based chemotherapy achieving a radiologic complete (CR) or partial response. 12.4% patients with stable disease were also included. Median PFS was 14.7 months (95% CI:12.6-18), with statistically longer PFS in patients with normal serum Ca125 at baseline, a CR after last platinum based therapy and that received olaparib after second platinum based therapy. Median OS was not reached. Most frequent G3-G4 toxicity was anaemia (6%) with dose discontinuation and dose reduction in 11 (4.7%) and 49 (20.9%) of cases, respectively. Among 66 patients receiving further treatment after olaparib progression and evaluable for response, ORR was 22.2, 11.1% and 9.5% in patients with Platinum Free interval (PFI) of more than 12 months, between 6 and 12 months and less than 6 months, respectively. Olaparib is effective and safe in real world setting. Data on post-progression treatments seem to suggest cross resistance with chemotherapy and need to be confirmed in larger studies because of the potential importance in clinical practice decisions.