Merck (NYSE:MRK) reported a strong opening to 2026, with worldwide sales climbing 5% to $16.3 billion, driven by the continued dominance of its blockbuster cancer therapy and the rapid uptake of its newly launched cardiovascular portfolio.
Excluding the impact of foreign exchange, revenue grew 3% for the quarter ended March 31, 2026.
The company's oncology cornerstone, Keytruda, remains its primary growth engine, with sales rising 12% to $8 billion.
This figure includes $128 million from Keytruda QLEX, the company's subcutaneous formulation.
Beyond oncology, Merck’s pivot into the pulmonary arterial hypertension market showed significant momentum; Winrevair sales hit $525 million, an 88% surge that underscores the drug's rapid adoption following its recent approval.
Despite the top-line growth, Merck reported a GAAP loss per share of $1.72 and a non-GAAP loss of $1.28.
These figures were heavily impacted by a $3.62 per share charge related to the acquisition of Cidara Therapeutics.
This strategy of aggressive inorganic growth is set to continue, as the company recently announced an agreement to acquire Terns Pharmaceuticals to bolster its hematology pipeline.
The Terns transaction, expected to close in May, is anticipated to result in a one-time charge of approximately $5.8 billion.
The quarter was also marked by significant regulatory and clinical progress.
Merck received FDA approval for IDVYNSO, a once-daily oral treatment for HIV-1, and presented positive Phase 3 data for its cardio-pulmonary candidate in the CORALreef AddOn trial.
The Animal Health division also provided a solid baseline of growth, with sales increasing 13% to $1.8 billion.
Reflecting the strength of its core brands, Merck narrowed and raised the midpoint of its full-year 2026 sales guidance, now expecting revenue between $65.8 billion and $67.0 billion.