(Alliance News) - Merck & Co Inc on Thursday swung to a loss but reported higher sales for the first quarter, helped by growth in cancer drug Keytruda.

The Rahway, New Jersey-based pharmaceutical firm swung to a net loss of USD4.24 billion in the first quarter from a profit of USD5.09 billion a year prior.

The loss per share was USD1.72, swung from earnings per share of USD2.01 a year prior. Merck said this includes a charge of USD3.62 per share for the acquisition of Cidara Therapeutics Inc.

Sales climbed 4.9% to USD16.29 billion from USD15.53 billion. However, research & development costs multiplied to USD12.59 billion from USD3.62 billion, and cost of sales jumped 23% to USD4.20 billion from USD3.42 billion.

Selling, general and administrative costs were up 5.8% at USD2.70 billion from USD2.55 billion.

Sales for Keytruda were 12% higher at USD8.03 billion from USD7.21 billion. Merck said this was primarily driven by higher global demand in metastatic indication including urothelial cancer, as well as "strong global uptake" in earlier-stage indications.

"We are moving with speed to transform our portfolio to one with a diversified set of growth drivers across a broad set of therapeutic areas," said Chief Executive Officer Robert Davis.

"I am pleased with our progress and excited for what's ahead, as we enter a particularly robust period of phase three data readouts and deliver on the promise of our pipeline for patients."

Looking ahead, Merck narrowed and raised the midpoint of its expects sales range. It now expects 2026 sales between USD65.8 billion and USD67.0 billion, up from between USD65.5 billion and USD67.0 billion in previous guidance. It reported 2025 sales of USD65.01 billion in 2025.

Merck now expects non-GAAP earnings per share between USD5.04 and USD5.16, up from between USD5.00 and USD5.15, including a one-time charge of USD3.62 per charge for the acquisition of Cidara. Non-GAAP EPS was USD8.98 in 2025.

The firm said this outlook does not reflect any impact from the proposed acquisition of Terns Pharmaceuticals Inc. This is expected to close in May and result in a one-time charge of around USD5.8 billion or around USD2.35 per share.

Shares in Merck & Co were down 1.8% at USD108.99 during premarket trading on Thursday morning in New York.

By Michael Hennessey, Alliance News reporter

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