IDDF2019-ABS-0152\u2005A single-center phase ii study of apatinib combined with s1 as a maintenance treatment in metastatic gastric cancer patients

Abstract

Background Antiangiogenesis therapy plays an important role in cancer treatment. Apatinib mesylate, a small molecule tyrosine kinase inhibitor targeting vascular endothelial growth factor receptor-2(VEGFR-2), has been recommended as a third-line treatment for metastatic gastric cancer patients. This study was conducted to assess the efficacy and safety of apatinib combined with S1 as a maintenance treatment in metastatic gastric cancer patients. Methods This single-center, open-label, single arm study enrolled patients with metastatic gastric cancer patients, pretreated chemotherapy with S1 regimens and their efficacy of chemotherapy was stable. The primary end point of this study was progression-free survival (PFS). Secondary end points included objective response rate (ORR), disease control rate (DCR), and toxicity. Apatinib was administered as 500 mg daily on days 1 through 28 of each 4-week cycle, and S1 35–40 mg/m2 take orally twice a day on 1 through 14 of each 3-week cycle. Results So far, the study is continuing, and 15patients were enrolled with a median age of 52 years (range, 33 to 62 years) and received apatinib with S1 for a median of 4 cycles (range from 0 to 10 cycles). 11 (73.3%) patients experienced dose reduction during treatment. Median PFS of all 15 patients was 8.6 months (95% confidence interval (CI), 4.5m - 13.7m). 12 patients were eligible for efficacy analysis. ORR was 33.3% (4/12). DCR was 66.7% (8/12). The most common grade 3/4 treatment-related AEs were hypertension 25.0%(3/12), hand-foot syndrome 8.3%(1/12), and proteinuria 8.3%(1/12). Of two possibly drug-related SAEs recorded in the study, 1 death occurred within 28 days of last treatment and was considered to be the result of disease progression. Conclusions Apatinib combined with S1 as a maintenance treatment can prolong PFS in patients with metastatic gastric cancer, and the toxicity is manageable. Apatinib combined with S1 exhibited objective efficacy and it might be better to be tested in metastatic gastric cancer. The maintenance therapy of metastatic gastric cancer is worthy of clinical randomized controlled study.