FDA Approves Keytruda to Treat Lung Cancer

In October, the U.S. Food and Drug Administration (FDA) granted accelerated approval for pembrolizumab (Keytruda, Merck & Co.) for treatment of patients with advanced (metastatic) non-small cell lung cancer (NSCLC) across all histologies whose disease has progressed on or after platinum-containing chemotherapy, as well as a targeted agent in epidermal growth factor receptor- or anaplastic lymphoma kinase-positive patients. The programmed death (PD-1) inhibitor is the second immunotherapy available for this type of tumor. It was approved along with a companion diagnostic, the PD-L1 IHC 22C3 pharmaDx test, which is the first test designed to detect PD-L1 expression in non-small cell lung tumors.

The approval is based in part on data from the KEYNOTE-001 trial that led to the drug being granted a breakthrough therapy designation by FDA in October 2014. Results of that trial show that pembrolizumab had an overall response rate of nearly 20 percent among 495 previously treated-naive patients with advanced or metastatic NSCLC. The overall response rate was 45.2 percent among a cohort of patients with high PD-L1-expressing NSCLC. The median duration of response exceeded one year in all responders regardless of the degree of PD-L1 expression. And, median overall survival was 12 months for all patients, 9.3 months for previously treated patients and 16.2 months for previously untreated patients. The most common adverse effects included fatigue, decreased appetite, shortness of breath or impaired breathing, and cough. The drug also has the potential to cause severe immune-mediated adverse effects.

Pembrolizumab had been previously granted FDA approval for use in advanced melanoma.