Pembrolizumab Immunotherapy FDA Approved for Lung Cancer

The immunotherapy, pembrolizumab (Keytruda), has been FDA approved for treatment in patients with pretreated advanced non­—small cell lung cancer (NSCLC) across all histologies with tumors expressing programmed cell death ligand 1 (PD-L1). The PD-1 inhibitor was approved along with a companion diagnostic, the PD-L1 IHC 22C3 pharmDx test.

“Our growing understanding of underlying molecular pathways and how our immune system interacts with cancer is leading to important advances in medicine,” said Richard Pazdur, MD, director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research. “Today’s approval of Keytruda gives physicians the ability to target specific patients who may be most likely to benefit from this drug.”

The approval was based on data from the phase I KEYNOTE-001 trial, in which the overall response rate with the drug was 41% among a subgroup of 61 patients with PD-L1­—positive tumors as determined by the 22C3 pharmDx diagnostic test. The patients received 10 mg/kg of pembrolizumab every 2 or 3 weeks. Response duration ranged from 2.1 to 9.1 months.

Overall, the KEYNOTE-001 trial included 495 previously treated and treatment-naïve patients with advanced or metastatic NSCLC. The total population comprised a training set of 182 patients and a validation set of 313 patients. Pembrolizumab was administered at three dosages: 2 mg/kg every 3 weeks, 10 mg/kg every 3 weeks, or 10 mg/kg every 2 weeks. The researchers assessed patient responses every 9 weeks.

Pembrolizumab is now the second FDA-approved PD-1 inhibitor in lung cancer, and first across all NSCLC histologies. The PD-1 agent nivolumab (Opdivo) was approved in March 2015 for patients with NSCLC who have progressed on or after platinum-based chemotherapy; however, the indication is limited to individuals with squamous histology.

Nivolumab recently received an FDA priority review designation in the nonsquamous NSCLC setting. Under the expedited process, the FDA’s decision deadline is January 2, 2016.

Beyond lung cancer, pembrolizumab is also approved for patients with advanced melanoma.