In lung cancer, pembrolizumab (Keytruda) provided a durable and clinically relevant long-term OS benefit versus chemotherapy, with twice as many patients living 5 years or longer.
The study involved patients with previously untreated non–small-cell lung cancer (NSCLC) with a programmed death ligand-1 (PD-L1) tumor proportion score of at least 50%, and no sensitizing EGFR or ALK alterations. 305 patients were randomly assigned to either pembrolizumab (n=154) or platinum-based chemotherapy (n=151). Five-year overall survival (OS) was 31.9% in pembrolizumab-treated patients and 16.3% for patients who received chemotherapy, the investigators reported in the Journal of Clinical Oncology. Median OS was 26.3 months for pembrolizumab and 13.4 months for chemotherapy.
Patients in the chemotherapy group with progressive disease could cross over to pembrolizumab, and of the patients initially assigned to chemotherapy, 99 also received anti–PD-1 or PD-L1 therapy, representing a 66% effective crossover rate. The authors note that this high effective crossover rate may reduce the observed effect of pembrolizumab versus chemotherapy, and that “these data continue to support a first-line immunotherapy approach, which permits early inhibition of PD-1 signaling, in this patient population.”
Source: Journal of Clinical Oncology