Aims: Pembrolizumab is approved as first-line (1L) treatment for advanced NSCLC patients with PD-L1 tumor proportion score (TPS) ≥50% and as treatment for previously treated advanced NSCLC patients with PD-L1 TPS ≥1%. We present 3-y OS results for patients enrolled in KEYNOTE-001 (NCT01295827), the first trial evaluating pembrolizumab in advanced NSCLC patients.
Methods: 550 patients received pembrolizumab 2 or 10 mg/kg Q3W or 10 mg/kg Q2W until intolerable toxicity, progression, or investigator or patient decision to withdraw. PD-L1 expression was assessed by IHC using the 22C3 antibody. Survival was assessed every 2 mo after treatment discontinuation.
Results: 550 advanced NSCLC patients enrolled; 101 were first line (1L), and 449 were previously treated. As of the Sept 1, 2016, data cutoff, median follow-up duration was 34.5 mo (range, 25.7-51.5 mo); 8 (7.9%) 1L patients and 28 (6.2%) previously treated patients were still on treatment. 3-y OS was 26.4% (95% CI, 14.3%-40.1%) in 1L patients and 19.0% (95% CI, 15.0%-23.4%) in previously treated patients. Median (95% CI) OS was 22.3 mo (17.1-31.5) in 1L patients and 10.5 mo (8.6-13.2) in previously treated patients. 3-y OS rate (95% CI) by PD-L1 status in 1L patients was TPS ≥1% (n=79): 16.4% (4.0-36.36); TPS ≥50% (n=27): 25.2% (5.0-53.1); and not available for TPS 1%-49% (n=52). In previously treated patients, 3-y OS rate (95% CI) by PD-L1 status was TPS ≥1% (n=306): 21.1% (16.1-26.6); TPS ≥50% (n=138): 29.7% (21.9-37.9); TPS 1%-49% (n=90): 13.5% (7.8-20.9); and TPS<1% (n=90): 8.5% (2.9-18.1). Additional description of long-term outcomes, including updated safety data and 3-y OS by PD-L1 status and in patient subgroups, will be presented.
Conclusions: Pembrolizumab provides promising long-term OS benefit for 1L and previously treated advanced NSCLC patients expressing PD-L1. The current data represent the longest efficacy and safety follow-up for patients with advanced NSCLC treated with pembrolizumab.