Merck's Keytruda threatens Pfizer, Merck KGaA's Bavencio with Merkel cell 'priority' tag

The FDA expects to make a decision on Keytruda in Merkel cell carcinoma by the end of this year. (Merck)

Merck is getting ready to take on Pfizer and Merck KGaA’s Bavencio in a rare form of skin cancer, and the FDA just sped up the showdown.

The FDA has tapped the New Jersey drugmaker’s immuno-oncology standout Keytruda for a priority review in Merkel cell carcinoma, an aggressive cancer that affects about 2,500 new patients each year in the U.S. The designation will speed Keytruda’s trip down the regulatory pathway, and if approved, it’ll bear a green light in patients with recurrent locally advanced or metastatic forms of the disease. The agency expects to make a decision by Dec. 28, Merck said. 

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Right now, Bavencio is the only drug in the PD-1/PD-L1 class approved to treat the disease, thanks to a March 2017 accelerated approval from U.S. regulators that put the product on the market for the first time. But a go-ahead for Keytruda could threaten its sales, which Merck KGaA said amounted to just $17 million in Q2.

Pfizer and Merck KGaA won’t exactly welcome the new competition. Bavencio bears just one other U.S. approval, and that one’s in bladder cancer, the most crowded of fields for immuno-oncology drugmakers: All five drugs in the class—Bavencio, Keytruda, Bristol-Myers Squibb’s Opdivo, AstraZeneca’s Imfinzi and Roche’s Tecentriq—compete in the space.

Keytruda, on the other hand, has steamrolled lately with a host of new approvals, including a key new nod in previously untreated lung cancer, the class’ most lucrative market. Before that, in June, it snagged two thumbs ups in two days, winning FDA blessings in non-Hodgkin lymphoma and cervical cancer.

RELATED: The day has come: Merck’s Keytruda surpasses Bristol-Myers Squibb’s Opdivo in Q2 sales

And sales have benefited from the drug’s regulatory spree, which has particularly picked up over the last couple of years. In the second quarter, Keytruda raked in $1.67 billion to narrowly top Opdivo, the previous class leader, with $1.63 billion during the period.