TY - JOUR T1 - 674 Niraparib as maintenance therapy in platinum-sensitive recurrent ovarian cancer: a GEICO study within the Spanish extended access program JF - International Journal of Gynecologic Cancer JO - Int J Gynecol Cancer SP - A261 LP - A261 DO - 10.1136/ijgc-2021-ESGO.447 VL - 31 IS - Suppl 3 AU - JF Cueva Bañuelos AU - I Palacio AU - C Churruca AU - A Herrero-Ibáñez AU - B Pardo AU - M Constenla AU - A Santaballa AU - L Manso AU - P Estévez AU - C Maximiano AU - M Legerén AU - G Marquina AU - A De Juan AU - M Quindós AU - L Sánchez AU - A Barquin AU - I Fernández Pérez AU - C Martín-Lorente AU - A Juárez AU - A González-Martín Y1 - 2021/10/01 UR - http://ijgc.bmj.com/content/31/Suppl_3/A261.1.abstract N2 - Introduction/Background*In the ENGOT-OV16/NOVA trial, niraparib demonstrated a significantly longer PFS in patients (pts) with recurrent platinum-sensitive ovarian cancer (PSOC) vs placebo as maintenance therapy, regardless of gBRCA/HRD status. Niraparib obtained EU approval in 2017 and an expanded access program (EAP) was initiated.Methodology A retrospective study of niraparib maintenance therapy was conducted within the Spanish EAP, at 57 hospitals. Niraparib’s safety, dose adjustments, and effectiveness in real-world setting were assessed. Patient characteristics and starting dose individualizations were also analyzed. EAP’s inclusion required at least 2 previous courses of platinum-containing therapy. For the last course prior to inclusion a response should have been obtained. Although BRCAmut and BRCAwt pts could be included, most were BRCAwt because olaparib was commercialized at that time for pts with BRCAmut and pts were allowed to be included only in specific circumstances.Result(s)*Between September 2020 and March 2021, 316 pts were included. Median age was 63 years (31-88). More common initial FIGO stages were IIIC, IVB, and IVA (50.0%, 13.6%, 11.1%). 5.7% were BRCAmut, 80.4% BRCAwt, and 13.9% unknown. 93.4% had initial surgery and 22.8% after relapse. Previous bevacizumab was given in 40.8% of pts. Before niraparib, pts had ECOG 0-1 (50.3%-47.5%) and 55.7% had measurable disease. Population weights (Kg) were 43-57 (23.1%), 58-76 (52.2%), and 77-105 (17.7%). 19.7% had baseline platelets <150,000/µL, with a median of 203,500/µL. Individualized starting dose (ISD) was applied in 203 pts (64.2%); 142 (70%) of them started at 200 mg. Niraparib’s mean dose was 201.5 mg (59.2% had ≥1 reduction and 63.3% ≥1 interruption). 6.0% discontinued due to niraparib-related adverse events. Main G3-4 hematological toxicities were thrombocytopenia (17.4% ISD-32.0% fixed starting dose (FSD)), anemia (12.4% ISD-17.5% FSD), and neutropenia (7.5% ISD-5.8% FSD). There were not relevant G3-4 non-hematological events. 58 (18.3%) pts were long-term responders (treatment ≥1 year). 47 (14.9%) remained on treatment upon analysis.Conclusion*The use of niraparib as maintenance therapy in pts with recurrent PSOC in real-life setting is safe. The ISD approach improved the safety profile. Results were in accordance with those reported in phase III trials. Overall effectiveness analysis is coming. ER -