Sintilimab Plus Apatinib and Chemotherapy as Second‑/Third-Line treatment for Advanced Gastric or Gastroesophageal Junction Adenocarcinoma: a prospective, Single-Arm, phase II trial

BACKGROUND: The prognosis of patients with previously treated advanced gastric or gastroesophageal junction (GEJ) cancer remains poor. Given the robust development of immunotherapy and targeted therapy during the last decades, we aimed to investigate if the combination of traditional second-line chemotherapy with sintilimab and apatinib could bring survival benefits for these patients. METHODS: In this single-center, single-arm, phase II trial, patients with previously treated advanced gastric or GEJ adenocarcinoma received specific dose level of intravenous paclitaxel or irinotecan (investigator’s choice), 200 mg intravenous sintilimab on day 1, and 250 mg oral apatinib once daily continuously in each cycle until disease progression, intolerable toxicity, or withdrawal of consent. The primary endpoints were objective response rate and progression-free survival. The secondary endpoints were mainly overall survival and safety. RESULTS: From May 2019 to May 2021, 30 patients were enrolled. At the data cutoff date (March 19, 2022), the median follow-up duration was 12.3 months and 53.6% (95% CI, 33.9–72.5%) patients achieved objective response. The median progression-free survival and overall survival were 8.5 months (95% CI, 5.4–11.5) and 12.5 months (95% CI, 3.7–21.3), respectively. Grade 3–4 adverse events included hematological toxicities, elevated alanine aminotransferase, elevated aspartate aminotransferase, elevated alkaline phosphatase, elevated gamma-glutamyl transpeptidase, hyperbilirubinemia and proteinuria. The most frequent grade 3–4 adverse event was neutropenia (13.3%). No serious treatment-related adverse events or treatment-related deaths occurred. CONCLUSION: Sintilimab plus apatinib and chemotherapy demonstrates promising anti-tumor activity with manageable safety profile in patients with previously treated advanced gastric or GEJ cancer. TRIAL REGISTRATION: ClinicalTrials.gov: NCT05025033, 27/08/2021.