A multicenter, open-label phase II trial of second-line apatinib plus irinotecan in patients with advanced gastric cancer.

287 Background: The best choice of second-line chemotherapy regimen for patients with advanced gastric cancer is still debated. Anti-VEGF target therapy is proven to be effective both in second and third line settings. Apatinib, a highly selective VEGFR2 inhibitor, has been demonstrated to be efficacious and well-tolerated for third line of treatment in gastric cancer. The aim of this study is to evaluate the safety and efficacy of apatinib in combination with irinotecan in the second line treatment of advanced gastric cancer. Methods: With the expectation of improving PFS to 4.4m, this investigator-initiated, single arm, multi-center, registered phase II prospective study was designed to enroll 62 eligible patients diagnosed with advanced gastric cancer. Each participant was expected to receive chemotherapy plus apatinib (irinotecan 1800mg/m2, d1, Q2W; apatinib 500mg po qd). The severity of side effects was established according to Common Terminology Criteria for Adverse Events (CTCAE),Version 4.0. Efficacy assessed every three cycles (6 weeks) during the study. The primary endpoint was PFS. The secondary endpoint was OS, ORR, and DCR. The tumor response was determined according to RECIST 1.1 criteria. Results: Baseline characteristics (FAS population): From March 2019 to April 2021, 31 patients from 4 centers in Guangdong province were enrolled. Among them, 28 are eligible for analysis. There are 16 females and 15 males, median age 55 years old. Safety: 82.4% patients reported adverse events (AEs). The incidence of grade 3-4 AEs was 52.9%. Main 3-4 AEs were neutropenia (32.4%), leucopenia (17.6%), anorexia (8.8%), hypoalbuminaemia (8.8%), thrombocytopenia (5.9%), nausea (5.9%). Efficacy: By Aug 31th, 2021, 28 patients were evaluable for response and survival, 1 of them achieved complete response (CR), 10 of them achieved partial response (PR), 8 achieved stable disease (SD), and 9 experienced progression disease (PD). The ORR is 35.48%, the DCR is 61.29%. Median PFS is 4.40m, median OS is 6.64m. Conclusions: Adding apatinib to irinotecan chemotherapy as the second line treatment would be well tolerant in patients with advanced gastric cancer. This indicated the combination could be a potential treatment option for patients with advanced gastric cancer. Clinical trial information: ChiCTR1900021377.