Merck's Keytruda nabs 2nd approval in 2 days, this time in non-Hodgkin lymphoma

Another day, another approval for Merck immuno-oncology star Keytruda.

On Wednesday, the drug picked up an FDA green light to treat patients with a rare type of non-Hodgkin lymphoma whose cancer has come back after two or more prior lines of treatment. And that go-ahead came just one day after it snagged a nod in cervical cancer.

With Keytruda’s latest OK, Merck became the only immuno-oncology drugmaker that can flaunt an approval in primary mediastinal large B-cell lymphoma, which develops when abnormal white blood cells build up between the lungs and the breast bone. And the New Jersey pharma can say the same with cervical cancer, too.

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While neither market is anywhere near the size of the mammoth lung cancer market Keytruda is dominating, the regulatory blessings will help the product build its lead on rivals Opdivo from Bristol-Myers Squibb, Roche’s Tecentriq, AstraZeneca’s Imfinzi, and Pfizer and Merck KGaA’s Bavencio. All of those therapies are fellow members of the PD-1/PD-L1 class, and they’re racing to rack up indications, particularly in arenas without in-class competition.

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The FDA granted Keytruda an accelerated approval for both adult and pediatric PMBCL patients after a study showed the drug could provoke a response in 45% of study patients. All patients had received Roche’s Rituxan as part of their prior treatment.

It’s not the first lymphoma approval for Keytruda, which scored an indication in classical Hodgkin lymphoma last March. Elsewhere in the blood cancer realm, though, it’s faced setbacks. Last July, the FDA stopped Keytruda studies in multiple myeloma following trial deaths.