Phase 2 study of first-line pembrolizumab monotherapy in elderly patients with non-small-cell lung cancer expressing high PD-L1.

While this study showed that pembrolizumab was a tolerable treatment for elderly patients, the safety requires further confirmation in a larger study. Although the primary endpoint, the median PFS (9.6 months), was slightly shorter than that (10.3 months) of the previous phase III study (KEYNOTE-024 study), the median PFS did not achieve the expected value.