The maker of pembrolizumab, a programmed death 1 (PD-1) inhibitor (Keytruda; Merck), announced phase II/III trial results showing that the drug resulted in better overall survival (OS) and progression-free survival (PFS) compared with docetaxel in patients with non–small-cell lung cancer (NSCLC). The study included only patients who had failed prior systemic therapy and whose tumors expressed programmed death ligand 1 (PD-L1).
“The results from this trial provide part of a growing body of evidence supporting the potential of Keytruda in the treatment of NSCLC,” said Merck’s president, Roger M. Perlmutter, MD, PhD, in a press release.
The KEYNOTE-010 trial results have not yet been presented or published. The study compared two doses of pembrolizumab (2 mg/kg and 10 mg/kg) with docetaxel in 1,034 patients. All had progressed following treatment with platinum-containing systemic therapy, and all had tumors expressing PD-L1.
According to Merck’s release, pembrolizumab was associated with longer OS, in both the 2-mg/kg and 10-mg/kg dose groups, compared with docetaxel. This survival benefit was seen both in a subgroup of patients with PD-L1 expression tumor proportion scores of 50% or higher, as well as in all enrolled patients (all had a score of 1% or higher).
Both doses also resulted in longer PFS vs docetaxel in the 50% or higher group; this was not statistically significant in the full cohort of patients.
Pembrolizumab received an accelerated approval from the US Food and Drug Administration (FDA) in early October (at the 2-mg/kg dose level). The FDA noted in a press release that the most common side effects in a safety cohort of 550 patients included fatigue, dyspnea, and decreased appetite.
Earlier this year, results of a phase I study of pembrolizumab yielded promising survival outcomes. The median OS in that cohort of 495 patients was 12.0 months, and there was an overall response rate to the drug of 19.4%; this was higher in patients who had not received any previous treatment.
Pembrolizumab is not the first immunotherapy agent approved for the treatment of NSCLC. The FDA granted approval to nivolumab (Opdivo; Bristol-Myers Squibb) for the treatment of metastatic squamous NSCLC in March, and the indication was expanded to advanced non-squamous NSCLC in October.