After two years of treatment, a complete response was achieved.<h4>Conclusions</h4>The combination of anti-HER-2 bispecific targeting therapy and PD-1/CTLA-4 bispecific immunotherapy demonstrated promising efficacy and a favorable safety profile in this patient with advanced HER2-positive gastric cancer, achieving durable complete response without chemotherapy. The gene discussed is CTLA4; the disease is gastric cancer.