The addition of pembrolizumab to chemotherapy continued to improve overall survival and progression-free survival compared with chemotherapy alone in patients with metastatic squamous non-small cell lung cancer (NSCLC), according to a final analysis of KEYNOTE-407.1
These results confirm earlier conclusions from the trial and provide data on progression after next-line treatment.
In KEYNOTE-407, patients were randomly assigned to receive pembrolizumab plus carboplatin and paclitaxel/nab-paclitaxel (278 individuals) or chemotherapy alone (281 individuals). Trial results showed that pembrolizumab significantly improved median overall survival (median 17.1 months vs 11.6 months; hazard ratio [HR], 0.71; 95% CI, 0.58-0.88) and progression-free survival (median 8 months vs 5.1 months; HR, 0.57; 95% CI, 0.47-0.69).
“The improvement in overall survival achieved in the pembrolizumab plus chemotherapy arm occurred despite a high crossover rate: approximately half of patients in the placebo plus chemotherapy group received subsequent anti-PD(L)1 therapy,” the researchers wrote.
In this update, the researchers also looked at time from randomization to progression on next-line treatment or death (PFS2). Patients randomly assigned to first-line pembrolizumab plus chemotherapy had a longer PFS2 compared with chemotherapy alone (HR, 0.59; 95% CI, 0.49-0.72). The median PFS2 was 13.8 months for the pembrolizumab arm compared with 9.1 months for the chemotherapy alone arm. The PFS2 benefit seen with pembrolizumab occurred regardless of PD-L1 status.
According to the researchers, this result demonstrates “that the clinical benefits of pembrolizumab were maintained after initial progression” and provide “support for the first-line combination over second-line pembrolizumab monotherapy.”
Discontinuation of any treatment because of adverse events occurred more commonly among patients assigned pembrolizumab compared with chemotherapy alone (27.3% vs. 13.2%). However, the rate of grade 3-5 adverse events was similar in both arms.
Paz-Ares L, Vicente D, Tafreshi A, et al. A randomized, placebo-controlled trial of pembrolizumab plus chemotherapy in patients with metastatic squamous non-small-cell lung cancer: protocol-specified final analysis of KEYNOTE-407 [published online June 26, 2020]. J Thoracic Oncol. doi: 10.1016/j.jtjo.2020.06.015