OA03.06 Evaluation of Toxicity Profile of PD-1 versus PD-L1 Inhibitors in Non-Small Cell Lung Cancer (NSCLC)

Abstract

Monoclonal antibodies against Programmed Death 1 (PD-1) and Programmed Death Ligand 1 (PD-L1) have emerged as effective therapies in NSCLC. We updated our initial systematic review of trials investigating differences in the toxicities of PD-1 and PD-L1 inhibitors. An electronic literature search was performed of public databases (MEDLINE, EMBASE) and conference proceedings for trials utilizing PD-1 inhibitors (nivolumab, pembrolizumab) and PD-L1 inhibitors (atezolizumab, durvalumab, avelumab) in NSCLC patients. Studies that did not report toxicities were excluded. A formal meta-analysis was conducted with Comprehensive Meta-Analysis software (Version 2.2). Clinical and demographic characteristics, response, and toxicity data were compared between the two groups. Twenty-two studies reported between 2013-2016 were eligible for this analysis. The total number of patients evaluated for toxicities were 2,863 patients in the PD-1 group and 2,006 patients in the PD-L1 group. Patient characteristics % (PD-1/PD-L1): median age 64/65, male 58/56, smokers 82/83, squamous histology 25/32, performance status 0-1 98/100. There was no difference in response rate between PD-1 (17%) and PD-L1 (18%) inhibitors, p=0.3. The incidence of overall adverse events (AEs), immune related AEs, and pneumonitis trended in favor of the PD-L1 group but did not reach statistical significance (see table). In this updated systematic review involving 4,869 patients, the toxicity profiles of PD-1 and PD-L1 inhibitors in NSCLC patients are not significantly different.