Abstract 1450P
Background
The triweekly combination of oxaliplatin and S-1 (SOX3: oxaliplatin 130mg/m2, d1, S-1 80mg/m2, d1-14, q3w) has shown satisfactory efficacy in advanced gastric cancer (GC) or esophagogastric junction adenocarcinoma (GEJ) in clinical trials. However, many patients have to interrupt treatment in the real world due to its seriously intolerable toxicity. The poor compliance with SOX3 ultimately affects the overall efficacy. The aim of this trial was to study the efficacy and safety of modified biweekly SOX (SOX2) regimen as the first-line treatment in advanced GC or GEJ patients.
Methods
This study consisted of a single-arm clinical trial involving two cancer centers. Inclusion criteria were patients with pathologically confirmed unresectable or metastatic gastric or esophagogastric junction adenocarcinoma. SOX2 regimen included oxaliplatin 85mg/m2, d1, S-1 80mg/m2, d1-10, q2w for 8 cycles.
Results
Sixty-five advanced GC/GEJ patients were enrolled from April 2013 to July 2019. Their median age was 63 years and the median chemotherapy cycle was 7 cycles. Median progression-free survival (PFS) was 6.9 months (95% CI 3.6-10.2). Median overall survival was 15.1 months (95% CI 9.3-20.8). The objective response rate (ORR) was 50.8%, and the disease control rate (DCR) was 84.6%. Most toxicities were grade 1/2, including anemia (73.4%), leukopenia (47.7%), neutropenia (43.7%) and thrombocytopenia (34.9%). Nine cases (13.8%) had grade 3 toxicities, including thrombocytopenia (7.9%), neutropenia (4.7%), elevated bilirubin (3.1%) and anemia (1.6%). No grade 4 toxicity was observed in all patients.
Conclusions
SOX2 regimen showed a significantly lower drug-related toxicity and better tolerance. Patients treated with modified SOX2 regimen had a promising ORR, DCR and OS. It can be used as one of the first-line chemotherapy options for advanced GC or GEJ.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Shu Zhang.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.