PD-1/PD-L1 inhibitor monotherapy in recurrent or metastatic squamous cell carcinoma of the head and neck: a meta-analysis

PurposeTo evaluate the efficacy and safety of programmed cell death-1/programmed cell death-ligand 1 inhibitor monotherapy compared to the standard of care in the first-line setting for recurrent or metastatic head and neck squamous cell carcinoma.Materials and methodsThe PubMed, Embase, and Cochrane Library databases were searched for relevant randomized controlled trials. The clinical outcomes of overall survival, progression-free survival, objective response rates, and grade 3 or higher adverse events were analyzed using Stata SE 15 software with a significance level set to 0.05.ResultsWe identified four randomized controlled trials (1 nivolumab, 2 pembrolizumab, and 1 durvalumab), including a total of 2474 patients. The results of the meta-analysis showed pooled hazard ratios of overall and progression-free survival for programmed cell death-1/programmed cell death-ligand 1 inhibitor monotherapy of 0.82 (95% CI: 0.73–0.91, p < 0.001) and 0.96 (95%CI: 0.84–1.07, p < 0.001) and pooled odds ratios of objective response rates and grade 3 or higher adverse events of 1.04 (95%CI: 0.46–2.37; p = 0.926) and 0.28 (95%CI: 0.22–0.35, p < 0.001), respectively. Subgroup analysis showed that inhibitors for both programmed cell death-1 (nivolumab and pembrolizumab) and programmed cell death-ligand 1 (durvalumab) were associated with significantly longer overall survival (HR = 0.80, 95% CI: 0.70–0.90, p < 0.001 and HR = 0.88, 95%CI: 0.70–1.06, p < 0.001, respectively).ConclusionsProgrammed cell death-1/programmed cell death-ligand 1 inhibitor monotherapy showed more clinical benefit versus the standard of care in patients with recurrent or metastatic head and neck squamous cell carcinoma, with an acceptable safety profile.