Predictive effect of PD-L1 expression for immune checkpoint inhibitor (PD-1/PD-L1 inhibitors) treatment for non-small cell lung cancer: A meta-analysis

• Published in: International immunopharmacology 2020-03, Vol.80, p.106214, Article 106214
• Main Authors: Zhang, Binbin, Liu, Yi, Zhou, Sijing, Jiang, Huihui, Zhu, Ke, Wang, Ran
• Format: Article
• Language: English
• Subjects: Antibodies; Apoptosis; Biomarker; Biomarkers; Chemotherapy; Clinical trials; Confidence intervals; Immune checkpoint inhibitor; Immune checkpoint inhibitors; Immunosuppressive agents; Inhibitors; Lung cancer; Meta-analysis; Monoclonal antibodies; Non-small cell lung carcinoma; PD-1 protein; PD-L1; PD-L1 protein; Pembrolizumab; Small cell lung carcinoma; Subgroups; Survival; Targeted cancer therapy
• ISSN: 1567-5769; 1878-1705
• DOI: 10.1016/j.intimp.2020.106214

•Higher PD-L1 expression is associated with increased ORR on treatment with ICIs.•PD-L1 expression can be considered as an ORR biomarker in advanced NSCLC patients.•PD-L1 expression is not predictive tool of OS and PFS in advanced NSCLC patients. Programmed death-ligand-1 (PD-L1) is a well-known predictive biomarker in non-small cell lung cancer (NSCLC) patients, however, its accuracy remains controversial. Here, we investigated the correlation between PD-L1 expression level and efficacy of its inhibitors, and hence assessed the predictive effect of PD-L1 expression. Studies that evaluated the efficacy of programmed death-1 (PD-1)/ PD-L1 inhibitors in advanced NSCLC patients according to tumor PD-L1 expression levels were searched for on Medline, Cochrane Library, and Embase. The pooled risk ratio (RR) and 95% confidence intervals (95% CIs) were calculated for the objective response rate (ORR) with overall survival (OS) and progression-free survival (PFS) were measured in terms of hazard ratio (HR) and the corresponding 95% CIs. 1432 NSCLC patients from six randomized controlled trials (RCTs) were included and three PD-1/PD-L1 inhibitors (atezolizumab, nivolumab, and pembrolizumab) were used to treat the patients. A significantly higher ORR was observed in the high PD-L1 expression group compared to the low expression group (0.35 [95% CI, 0.30–0.40] vs 0.11 [95% CI, 0.09–0.14]). The results of the subgroup analysis, grouped by the type of drugs and antibodies which assess immune checkpoint inhibitors were identical with the pooled result. However, our study showed that PD-L1 expression was neither prognostic nor predictive of overall survival (OS) or progression-free survival (PFS) in patients treated with PD-1/PD-L1 inhibitors compared to chemotherapy. PD-L1 can be a predictive biomarker for ORR. Nevertheless, PD-L1 expression is not a good predictive tool for OS and PFS.