1250P - Camrelizumab plus apatinib combined with POF in patients with untreated advanced gastric cancer (UAGC): A single-center, open-label, single-arm, phase II trial (SYLT-017)

Background

Previous reports of POF demonstrated promising efficacy for patients with AGC (ASCO-GI 2019). Apatinib, a small molecule tyrosine kinase inhibitor, can be safely administered up to 850 mg daily combined with POF in AGC (ESMO 2019). The PD-1 inhibitor nivolumab provided superior OS, along with PFS benefit, in combination with chemotherapy in UAGC in the CheckMate-649 study. Camrelizumab, in combination with apatinib, has been demonstrated clinical benefits in multiple advanced solid tumors. On the basis of these results, we conducted this trial to evaluate the safety and efficacy of first-line camrelizumab plus apatinib combined with POF in patients with UAGC.

Methods

In this single-center, open-label, single-arm, phase II trial, we enrolled participants (≥18 years) with previously untreated, unresectable gastric or gastro-oesophageal junction adenocarcinoma, regardless of PD-ligand 1 (PD-L1) expression. HER2 positive was excluded. Patients received camrelizumab 200 mg every 2 weeks and apatinib 750 mg once per day in combination with the POF regimen: intravenous paclitaxel 135 mg/m², oxaliplatin 85 mg/m², levoleucovorin 200 mg/m² followed by 5-FU 2400 mg/m² as a 46-hour continuous infusion, every 14 days for 12 cycles. The primary end point was the objective response rate (ORR). Key secondary end points were disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and safety.

Results

Twenty participants were recruited from 12/2020 to 06/2021. The median follow-up was 12.0 (IQR 9.3–12.0) months. The ORR was 75.0% (95% CI: 54.2-95.8%) and the DCR was 100.0% (95% CI: 100-100%). The median PFS was 11.0 (95% CI: 7.0-15.0) months, and the median OS was 14.0 (95% CI: not estimable) months. Treatment-related grade 3 or 4 AEs occurred in 90.0% of patients, and the most common AEs were neutropenia (75.0%), leukopenia (35.0%), hypertension (30.0%), and fatigue (20.0%). The most common potential immune-related AEs included grade 1-2 hypothyroidism (25.0%).

Conclusions

Camrelizumab plus apatinib combined with POF as first-line treatment has shown promising efficacy and acceptable safety, and may be a favorable option for patients with UAGC.

Clinical trial identification

NCT04174339.

Editorial acknowledgement

Legal entity responsible for the study

Rongbo Lin.

Funding

This study was funded by Natural Science Foundation of Fujian Province (grant number 2019J01199).

Disclosure

All authors have declared no conflicts of interest.