Clovis Oncology, Inc. announced that the European Commission has approved the use of Rubraca® for a second indication, as monotherapy for the maintenance treatment of adults with platinum-sensitive relapsed high-grade epithelial ovarian, fallopian tube, or primary peritoneal cancer who are in response to platinum-based chemotherapy. This expands rucaparib’s indication beyond its initial marketing authorization in Europe granted in May 2018 and with this label expansion, rucaparib is now available to patients regardless of their BRCA mutation status. Rucaparib was the first PARP inhibitor licensed for an ovarian cancer treatment indication in the EU and is now the first to be available for both treatment and maintenance treatment among eligible patients. The EC authorization is based on data from the phase 3 ARIEL3 clinical trial, which found that rucaparib significantly improved progression-free survival in all ovarian cancer patient populations studied. Ovarian cancer is the sixth deadliest cancer among women in Europe, where more than 65,000 women are diagnosed annually.ii Moreover, the 80% to 85% of women diagnosed in the later stages of the disease (III and IV) have particularly poor outcomes.iii Ovarian cancer is challenging to treat, and most women will relapse after surgery and chemotherapy. Multiple studies, including the rucaparib ARIEL3 clinical trial, have demonstrated that maintenance treatment with a PARP inhibitor significantly extends median progression free survival as compared to observation. The ARIEL3 trial was a double-blind, placebo-controlled clinical trial of rucaparib that enrolled 564 women with recurrent epithelial ovarian, fallopian tube or primary peritoneal cancer in complete or partial response to platinum-based chemotherapy. Patients were randomized (2:1) to receive rucaparib tablets 600mg twice daily (n=375) or placebo (n=189). ARIEL3 successfully achieved its primary endpoint, of extending investigator-assessed progression-free survival versus placebo in all patients treated (intention-to-treat [ITT]), population, regardless of BRCA status; the key secondary endpoint of extending PFS as assessed by independent radiological review was also achieved. An exploratory analysis of patients in the ITT population with measurable disease at baseline showed a tumor response was reported in 18% (95% CI 12%–26%) of patients (n=26) on rucaparib compared to 8% (95% CI 3% – 17%) of patients (n=5) on placebo (p value = 0.0069), including 10 patients in the rucaparib group who achieved a complete remission. The overall safety profile of rucaparib is based on data from 937 patients with ovarian cancer treated with rucaparib monotherapy in clinical trials. Adverse reactions occurring in =20% of patients were nausea, fatigue/asthenia, vomiting, anaemia, abdominal pain, dysgeusia, alanine aminotransferase elevations, aspartate aminotransferase elevations, decreased appetite, diarrhoea, thrombocytopenia and creatinine elevations. The majority of adverse reactions were mild to moderate (Grade 1 or 2). Grade =3 adverse reactions occurring in >5% of patients were anemia (23%), ALT elevations (10%), fatigue/asthenia (10%), neutropenia (8%), thrombocytopenia (6%), and nausea (5%). The only serious adverse reaction occurring in > 2% of patients was anemia (5%). Adverse reactions that most commonly led to dose reduction or interruption were anemia (20%), fatigue/asthenia (18%), nausea (16%), thrombocytopenia (15%), and AST/ALT elevations (10%). Adverse reactions leading to permanent discontinuation occurred in 10% of patients, with thrombocytopenia, nausea, anaemia, and fatigue/asthenia being the most frequent adverse reactions leading to permanent discontinuation.