Efficacy and Safety of Anti-PD-1/PD-L1 Antibodies in Patients with Relapsed/Refractory Diffuse Large B-cell Lymphoma: A Meta-Analysis

Abstract

Background: There are currently no standard treatment regimens for patients with relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL) and only few treatment options are available. Programmed death receptor-1/programmed death receptor ligand-1 (PD-1/PD-L1) blockade is considered effective in the treatment of many malignancies, such as non-small cell lung cancer, melanoma and renal cancer. At present, most of the clinical studies on PD-1/PD-L1 blockade in DLBCL that have been published are in phases 1 and 2 trials; however, satisfactory therapeutic effects were not observed in these trials. The aim of this meta-analysis was to test the safety and efficacy of PD-1/PD-L1 blockade in R/R DLBCL. Methods: Original studies evaluating the effect of anti-PD-1/PD-L1 antibodies on R/R DLBCL were searched in PubMed, Cochrane Library, Web of Science and Medline databases from the establishment of the databases to January 2023. RevMan 5.20 statistical software was used for meta-analysis. The presence of publication bias was assessed using funnel plot. The efficacy and safety effects were combined by odds ratio (OR) with 95% confidence interval (CI). Results: A total of 49 papers were retrieved, while eight clinical studies were collected. The estimated effect of overall response rate (ORR) was [OR = 0.46, 95% CI (0.21, 1.01); p = 0.05], the estimated effect of complete response rate (CRR) was [OR = 0.23, 95% CI (0.12, 0.43); p < 0.001], while the estimated effect of progression-free survival (PFS) was [OR = 0.60, 95% CI (0.24, 1.51); p = 0.28]. The estimated effect of overall survival (OS) was [OR = 1.84, 95% CI (0.95, 358); p = 0.07]. In addition, the estimated effect of three levels of adverse events was [OR = 0.74, 95% CI (0.28, 1.96); p = 0.55]. Conclusions: Anti-PD-1/PD-L1 antibodies may increase the ORR and CRR of patients with R/R DLBCL.