Continuing Immunotherapy in Gastric Cancer: A New Report on PD-1 Inhibitors

Strategic Insights -

Fresh data on gastric cancer have been presented in a new report from the Sun Yat-Sen University Cancer Center. Research on the efficacy of PD-1 inhibitors for metastatic gastric cancer after progression on previous chemoimmunotherapy has shed light on the benefits of continuing immunotherapy. The study found that patients who received treatment beyond progression with PD-1 inhibitors had significantly longer progression-free survival and overall survival compared to those who discontinued treatment after progression.

Key Takeaways:

  • The study retrospectively identified 60 patients with metastatic gastric cancer who received oxaliplatin-based chemotherapy plus PD-1 inhibitor as first-line treatment.
  • Patients who continued treatment with PD-1 inhibitors beyond progression (TBP) had significantly longer median overall survival (mOS) and median progression-free survival (mPFS) compared to those who did not (NTBP) group (mOS: 9.0 vs. 5.0 months, P = 0.011; mPFS: 4.3 vs. 2.7 months, P = 0.03).
  • The study found that TBP was an independent prognostic factor for both mPFS and mOS in multivariate analysis.
  • Patients who were male, had a favorable ECOG (0-1), classified into diffuse histologic subtype, and achieved disease control in the prior chemoimmunotherapy were more likely to benefit from continuing immunotherapy.
  • The study concluded that PD-1 inhibitors based therapeutic strategy may be a reasonable option in second-line setting for MGC who progressed on prior immunotherapy.

Statistics:

  • 60 patients were retrospectively identified in the study.
  • The median overall survival (mOS) in the TBP group was 9.0 months.
  • The median progression-free survival (mPFS) in the TBP group was 4.3 months.
  • The mOS and mPFS in the NTBP group were 5.0 months and 2.7 months, respectively.
  • The study found that the TBP group had significantly longer mOS and mPFS compared to the NTBP group (P = 0.011 and P = 0.03, respectively).

Sources:

  • Clinical benefit of continuation of PD-1 inhibitors after progression on first-line chemoimmunotherapy in metastatic gastric cancer and biomarker exploration. BMC Cancer, 2025,25(1):1-12. (BMC Cancer - http://bmccancer.biomedcentral.com).
  • NewsRx. New Gastric Cancer Research from Sun Yat-Sen University Cancer Center Discussed (Clinical benefit of continuation of PD-1 inhibitors after progression on first-line chemoimmunotherapy in metastatic gastric cancer and biomarker exploration). Cancer Weekly. June 10, 2025; p 1065.