Who's No. 1? With $25B in sales, Merck's Keytruda looks to be the top-selling drug of 2023

With Merck reporting a whopping $25 billion sales haul for Keytruda on Thursday, the PD-1 cancer superstar appears to be the world’s top-selling drug in 2023.

Keytruda looks set to take over the top spot from Pfizer and BioNTech’s Comirnaty, which ruled the previous two years, scoring sales of $55.9 billion in 2022 and $55.1 billion in 2021, according to Drug Discovery and Development.

Pfizer recently reported $11.2 billion in global Comirnaty revenues for 2023, while BioNTech has yet to reveal results for the full year.

Before the pandemic, AbbVie’s immunology megablockbuster Humira enjoyed a decadelong run as the top-selling drug after it assumed the throne from Pfizer’s cholesterol-lowering treatment Lipitor.

Keytruda’s momentum has built throughout its decade on the market. By 2018, in just its fourth year on the market, Keytruda was already pulling down $7.2 billion in sales, ranking No. 5 among the world’s top-selling drugs. In the next two years, Keytruda ranked No. 2, but it was still far behind Humira.

During the pandemic, Keytruda closed the gap with Humira. In 2022, AbbVie’s drug recorded sales of $21.2 billion, compared to $20.9 billion for Merck’s treatment.

Last year, with Humira finally facing biosimilar competition in the U.S., its sales have plummeted while Keytruda’s have continued to spiral upward. Through the first three quarters of 2023, Humira had generated sales of $10.5 billion. The company will report its fourth-quarter and full-year results on Friday.

Keytruda’s quarterly performance shows its continuing growth, as the product generated sales of $5.8 billion in the first quarter of 2023, $6.3 billion each in the second and third quarters and $6.6 billion in the fourth quarter.

Keytruda’s sales accounted for 41.6% of Merck’s revenue in 2023 and 45% of its sales in the fourth quarter. In Thursday’s presentation, Merck Chief Financial Officer Caroline Litchfield credited Keytruda's surge in 2023 to recent approvals that have moved it into earlier lines of treatment including triple negative breast cancer and renal cell carcinoma.

“Growth was also driven by the strong global needs of patients with metastatic disease,” Litschfield said during a conference call. “We continue to be encouraged by the positive impact our recent approvals are having on certain patients with earliest stage non-small cell lung cancer.”

Edward Jones healthcare analyst John Boylan expects Keytruda’s momentum to continue in 2024, projecting (PDF) sales of $30 billion.

Keytruda’s run at the top could be short, however. Gaining ground quickly is Novo Nordisk’s semaglutide diabetes and obesity treatments Ozempic, Wegovy and Rybelsus. Last year, the drugs combined to post sales of 145.81 billion Danish kroner ($21.2 billion).