In Japan, S-1 + CDDP (SP) regimen has become a standard therapy for patients with advanced gastric cancer. To improve the further antitumor efficacy, DCS regimen, SP combined docetaxel, is considered as a promising candidate of new standard treatment. Meanwhile, S-1 + oxaliplatin (SOX) regimen is added to one of the standard treatment. Nab-paclitaxel is also developed for chemotherapy with gastric cancer in Japanese clinical practice. Nab-paclitaxel created with albumin-bound paclitaxel particles has high transferability to tumor tissues and does not cause hypersensitive reaction because of different chemical composition compared with docetaxel and paclitaxel. S-1, nab-paclitaxel, and oxaliplatin combination (we call “SNOW regimen”) will be a promising triplet therapy for advanced gastric cancer patients. Although we have to pay attention to chemotherapy induced neuropathy, we investigate the recommended dose of this regimen in phase I study. Furthermore, we consider efficacy and toxicity in phase II study.
In part of phase I study, this is a dose-escalation study using a standard 3 + 3 design followed by expansion cohorts. SNOW regimen consists of 28-day cycles with escalated dose of nab-paclitaxel (100-175 mg/m2 on day 1 and 15), fixed dose of oxaliplatin (65 mg/ m2 on day 1 and 15) and S-1 (80 mg/m2/day on day 1 to 14). The primary end points are assessment of dose limiting toxicities (DLTs) and determination of maximum tolerated dose (MTD) to investigate the recommended dose (RD) in subsequent phase II study. In part of phase II study, primary endpoint is objective response rate (ORR). Secondary endpoints are assessment of safety, progression-free survival (PFS), disease control rate (DCR), overall survival (OS), and time to treatment failure. Adverse events are monitored and graded according to CTCAE v4.0. This study is performed at institutes that participate in Hokkaido Gastrointestinal Cancer Study Group (HGCSG) and registered as UMIN000016788.
Clinical trial identification
Y. Komatsu: processes involved in this research with Taiho Pharmaceutical Co., Ltd. and Yakult Honsha Co., Ltd. All other authors have declared no conflicts of interest.