Ray of dawn: Anti-PD-1 immunotherapy enhances the chimeric antigen receptor T-cell therapy in Lymphoma patients

BACKGROUND: Chimeric antigen receptor T (CAR-T) cell therapy, a new adoptive cell therapy, has been widely used to treat lymphoma patients. Immune checkpoint blockade may improve the cytotoxicity of CAR-T cells by reducing the failure of CAR-T cells and improving antitumor activity. It has shown promising efficacy. METHOD: We searched PubMed, the Cochrane Library, Embase and Web of Science from January 2012 to August 2022 to find data reporting the results of CAR-T cells therapy combined with PD-1 in tumor patients. An updated search was conducted in October 2023. The partial response rate (PR), complete response rate (CR), objective response rate (ORR), mortality rate, and incidence of adverse reactions were calculated. RESULTS: We analyzed 57 lymphoma patients from 5 clinical trials. The pooled partial, complete and overall response rates were 21% (95% CI 0.06–0.39, I(2) = 0.37%), 27% (95% CI 0.03–0.60, I(2) = 60.43%) and 65% (95% CI 0.23–0.98, I(2) = 76.31%), respectively. The pooled incidence of cytokine release syndrome, neutropenia, fever, and fatigue was estimated to be 57% (95% CI 0.08–0.99, I(2) = 85.20%), 47% (95% CI 0.14–0.81, I(2) = 74.17%), 59% (95% CI 0.27–0.89, I(2) = 60.23%), and 50% (95% CI 0.13–0.87, I(2) = 73.89%), respectively. CONCLUSION: CAR-T-cell therapy combined with anti-PD-1 immunotherapy in the treatment of lymphoma patients has efficacy, and the most common adverse effect is fever. REGISTRATION: The protocol was registered in prospero, with the registration number CRD42022342647. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12885-023-11536-4.