Rucaparib for PARP inhibitor-pretreated ovarian cancer: A GEICO retrospective subgroup analysis from the Spanish...

The poly(ADP-ribose) polymerase inhibitor (PARPi) rucaparib is approved as maintenance therapy for patients with platinum-sensitive recurrent high-grade ovarian cancer (HGOC). The efficacy and safety of rucaparib after PARPi therapy are largely unknown; therefore, we analyzed outcomes in the subgroup of PARPi-pretreated patients from Spanish hospitals participating in the Rucaparib Access Program. This post hoc subgroup analysis explored baseline characteristics, treatment exposure, safety, effectiveness, and subsequent therapy among women receiving rucaparib 600 mg twice daily after at least one prior PARPi for HGOC. Of 14 women eligible for the analysis, 11 (79%) had tumors harboring BRCA1/2 mutations. Patients had received a median of 5 (range 3-8) treatment lines before rucaparib. Twelve patients (86%) had previously received olaparib and two (14%) niraparib; 12 patients received rucaparib as treatment for platinum-resistant HGOC, one as treatment for platinum-sensitive HGOC, and one as maintenance therapy. Progression-free survival was 0.2-9.1 months. One of seven patients assessable for response by RECIST achieved stable disease. Adverse events occurred in 11 patients (79%; grade 3 in 29%), leading to treatment interruption in eight patients (57%), dose reduction in six (43%), but treatment discontinuation in only one (7%). No new safety signals were observed. This is one of the first reported series of real-world data on rucaparib after prior PARPi for HGOC. In this heavily pretreated population, rucaparib demonstrated meaningful activity in some patients and tolerability consistent with previous prospective trials. Future investigation should focus on identifying patients who may benefit from rucaparib after prior PARPi exposure.