Abstract 578P
Background
Limited experience showed that patients (pts) with advanced gastric cancer (GC) may benefit from immunotherapy combined with standard chemo/chemoradiation, due to an abscopal effect potentiated by the blockade of PD1. A phase II study (Neo-PLANET) was conducted to evaluate the efficacy and safety of SHR-1210 therapy combined with chemoradiation in the perioperative period for locally advanced proximal GC.
Methods
Based on the two-stage Simon’s design, stage II will be activated if at least 1 pathological complete remission (pCR) was observed among 15 pts in stage I. A sequential regimen of one cycle chemo (Xelox), radiation (45 Gy in five weeks, capecitabin as synergy) and one cycle chemo, concurrently with five cycles of immunotherapy (SHR-1210 per 3 weeks) prior to the following radical surgery and 4 cycles adjuvant chemotherapy. The primary outcome was pCR rate, the planned sample size was 36 pts.
Results
Fifteen patients (female: 2, median age: 64 years) were analysed. The objective response rate (ORR) was 93.3%. A curative resection was carried out in 93.3% (n=14) of cases, while a palliative chemo was performed in 1 pts. 26.7% (n=4) of the pts achieved pCR. Most common treatment related AEs (TRAEs) was capillary hyperplasia (n=13). Grade III/IV TRAEs were seen in 3 pts (20%).
Conclusions
The data of stage I indicated that immunotherapy combined with standard chemoradiation was an effective and safe preoperative regimen for pts with locally advanced gastric cancer, and supported the second stage being proceeded.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Zhongshan Hospital.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.