Merck's full-year 2025 revenue guidance fell short of what some analysts were expecting, at a range of $64.1 billion to $65.6 billion.

Shares of Merck are sliding in early trading after the drugmaker surprised Wall Street with a lower-than-expected 2025 sales forecast due partly to a pause in shipments of one of its top-selling products to China.

Merck & Co Inc (NYSE:MRK) reported fourth-quarter sales of $15.62 billion, up 7% year over year and slightly beating the consensus estimate of $15.49 billion. Excluding the impact of foreign exchange,