Merck, the manufacturer of Keytruda® (pembrolizumab), has voluntarily withdrawn the drug’s FDA-approved indication to provide third-line treatment of metastatic small cell lung cancer (SCLC) in patients whose disease has progressed on or after platinum-based chemotherapy and at least one other prior line of therapy.

The indication was granted accelerated FDA approval in June 2019. Continued approval was contingent upon completion of a post-marketing requirement to establish the superiority of treatment with Keytruda based on overall survival (OS) rates in a clinical study. Although Keytruda met a study endpoint for progression-free survival, it did not meet the OS endpoint.

This change affects only the indication for third-line treatment of metastatic SCLC. It does not affect the approval of Keytruda’s more than two dozen other indications for cancer treatment.

Keytruda’s SCLC withdrawal follows a similar move by Bristol Myers Squibb. The manufacturer had been granted accelerated FDA approval for Opdivo® (nivolumab) in 2018 to provide third-line treatment for SCLC that had progressed after platinum-based chemotherapy and at least one other line of therapy. Like Keytruda, Opdivo did not meet the OS endpoint in a confirmatory trial. Bristol Myers Squibb voluntarily withdrew Opdivo’s third-line SCLC indication at the end of 2020.