LBA78 - Overall survival of perioperative or postoperative adjuvant oxaliplatin with S-1 versus adjuvant oxaliplatin with capecitabine in locally advanced gastric or gastro-oesophageal junction adenocarcinoma undergoing D2 gastrectomy: An updated analysis of RESOLVE trial

Background

The RESOLVE study demonstrated a disease-free survival (DFS) benefit from perioperative SOX compared to adjuvant CapOx in patients with gastric or gastro-oesophageal junction (G/GOJ) adenocarcinoma who underwent D2 gastrectomy. Here, we aim to update on the 5-year overall survival (5yOS%) results.

Methods

The phase III, open-label, randomized controlled RESOLVE study (NCT01534546) enrolled patients with stage cT4aN+M0 or cT4bNanyM0 G/GOJ adenocarcinoma. Patients were 1:1:1 randomly assigned to adjuvant CapOx, adjuvant SOX, or perioperative SOX and underwent standard gastrectomy with D2 lymphadenectomy. The adjuvant CapOx group received 8 cycles of oxaliplatin (130 mg/m², d1) with capecitabine (1000 mg/m², bid, d1-14). The adjuvant SOX group received oxaliplatin and oral S-1 at a dose depending on body surface area (40-60 mg bid, d1-14). The perioperative SOX group received 3 cycles of preoperative SOX plus 5 cycles of postoperative SOX followed by 3 cycles of S-1 monotherapy. The primary endpoint was 3-year DFS, and second endpoints included 5yOS% and safety.

Results

Between 08/2012 and 02/2017, 1022 patients were included in mITT population and analyzed. With a median follow up time of 62.8 months, 495 recurrences and 416 deaths were observed by 07/04/2022. Perioperative SOX improved 5yOS% compared with adjuvant CapOx (60.0% vs. 52.1%; HR 0.79, 95%CI [0.62-1.00]; p=0.049). Adjuvant SOX was not inferior to postoperative CapOx (61.0% vs. 52.1%; HR 0.77, 95%CI [0.61-0.98]; p=0.033). Perioperative SOX improved 5yDFS% compared with adjuvant CapOx (53.2% vs. 45.8%; HR 0.79, 95%CI [0.63-0.98]; p=0.034). Adjuvant SOX was not inferior to adjuvant CapOx (50.8% vs. 45.8%; HR 0.86, 95%CI [0.69-1.06]; p=0.164). No additional adverse events were observed.

Conclusions

The update on the RESOLVE survival analysis revealed improved survival in patients with G/GOJ adenocarcinoma undergoing D2 gastrectomy with perioperative SOX therapy compared to adjuvant CapOx, and adjuvant SOX was not inferior to adjuvant CapOx.

Clinical trial identification

NCT01534546.

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Taiho Pharmaceutical Co., Ltd.

Disclosure

All authors have declared no conflicts of interest.