- Although Merck posted stellar results for Keytruda (pembrolizumab) in terms of increasing overall survival, it failed to achieve the target endpoint for progression-free survival (PFS).
- Earlier this month, Keytruda was approved by the FDA for second-line treatment of non-small cell lung cancer (NSCLC) tumors that express high levels of the PD-L1 protein. However, the approval, which was granted on an accelerated basis, was contingent upon the company conducting additional clinical trials to test effectiveness and safety.
- Merck would like to add the new data to its label and also hopes to expand the lung cancer indication.
The results of the trial were statistically significant versus docetaxel (standard of care) at both the 2 mg and 10 mg doses. But the PFS results were unexpected.
Still, patients with higher PD-L1 levels had longer PFS. Merck is still in the process of tabulating the data, with the goal of releasing it soon. Once that happens, the goal is to expand the label, as the drug currently has a second-line indication.
The competing Opdivo (nivolumab) from Bristol-Myers Squibb has consistently been a bit ahead of Merck in terms of racking up approvals for its checkpoint inhibitor with broader labels compared to Keytruda (for instance, not requiring lung cancer patients to express high levels of PD-L1). Nonetheless, analysts are bullish on both drugs, expecting $8.8 billion in sales for Opdivo by 2020, $5.5 billion in sales for Keytruda by 2020, and $20 billion overall for cancer immunotherapies as a class by 2020.