Merck’s Gardasil Sales Drop 39%, Enflonsia Q4 Revenue Slumps to $21 Million
Merck’s Gardasil sales plunged 39% year-over-year to $5.2 billion in 2025, prompting a temporary halt in China shipments and signaling continued weakness in Japan. New RSV antibody Enflonsia generated $21 million in Q4 versus $79 million in Q3, while Merck’s 2026 EPS estimate fell from $5.99 to $5.47.
1. Declining Gardasil Sales
Merck’s Gardasil sales fell 39% year-over-year to $5.2 billion in 2025, driven by weak demand in China and Japan. Elevated channel inventories at partner Zhifei prompted a temporary shipment halt in China to allow inventory normalization.
2. Enflonsia Sales Performance
The newly approved RSV antibody Enflonsia generated $21 million in fourth-quarter sales, down from $79 million in the third quarter. Lower infant immunization rates and high market inventory levels contributed to the quarterly decline.
3. Stock Performance and Valuation
Year-to-date, Merck shares have risen 10% compared with a 0.8% gain in the broader industry. The stock’s forward P/E ratio of 18.4 remains above the industry average of 17.89 and its five-year mean of 12.57.
4. Earnings Estimate Revisions and Analyst Rank
Merck’s 2026 EPS estimate was reduced from $5.99 to $5.47, and the 2027 estimate fell from $10.01 to $9.89 over the past month. The company holds a Zacks Rank of #4 (Sell), reflecting analyst caution on near-term growth.