Merck is broadening its pipeline as Keytruda’s patent cliff looms

Merck & Co.’s Keytruda is the world’s best-selling drug and has been a cancer juggernaut for more than a decade, scoring its 40th indication in June and adding yet another in late September.

As such, Keytruda accounted for about 42% of the company’s sales in 2023, which is a lot of weight to bear for a tentpole drug teetering on the edge of a patent cliff. That’s why the pharma giant is boosting the rest of its portfolio to ready itself for a world in which Keytruda will start facing biosimilar competition as early as 2028.