While Humira remains the best-selling prescription product worldwide, Keytruda has risen to the No. 2 global rank and is on track to eventually claim the top spot.

The U.S. Food and Drug Administration approved the anti-PD-1 therapy Keytruda as a monotherapy for patients with recurrent locally advanced or metastatic squamous cell carcinoma of the esophagus whose tumors express PD-L1 with disease progression after one or more previous lines of systemic therapy.