Slowing Gardasil Sales Hurt MRK's Top Line: Is Recovery in the Cards?

Merck's Gardasil sales are declining, primarily due to weak demand in China amid economic slowdown, resulting in a 40% year-over-year decrease in Q1 2025 to $1.33 billion and prompting a temporary halt of shipments to the region. This slowdown has led Merck to withdraw its long-term guidance of $11 billion in Gardasil sales by 2030, although sales remain strong in other major regions; analysts project a CAGR decline of 6.4% for Gardasil over the next three years. Despite these challenges, Merck received FDA approval for its RSV prevention antibody, Enflonsia, but it will face strong competition, and the consensus estimates for 2025 and 2026 earnings have slightly decreased.

Analysis

Merck faces significant headwinds from its second-largest product, Gardasil, with sales declining 40% year-over-year to $1.33 billion in Q1 2025 and 3% to $8.58 billion in 2024, primarily due to weak demand and an economic slowdown in China. This has led to elevated channel inventory with its partner Zhifei, prompting Merck to temporarily halt Gardasil shipments to China from February through at least mid-year 2025 and withdraw its previous long-term guidance of over $11 billion in Gardasil sales by 2030. While Gardasil sales remain strong in major regions outside China, such as the United States and Japan, Merck anticipates a slowdown in global growth ex-China, and model estimates project a 6.4% compound annual growth rate decline for Gardasil over the next three years. On a more positive note, Merck recently received FDA approval for Enflonsia, a prophylactic antibody for RSV prevention in infants, set to launch for the 2025-26 RSV season. However, Enflonsia will enter a highly competitive market, facing AstraZeneca/Sanofi’s Beyfortus, which achieved blockbuster status in 2024, along with Pfizer’s Abrysvo and GSK’s Arexvy. Merck's stock has underperformed, declining 17.8% year-to-date against an industry increase of 2.6%, though its valuation appears attractive with a forward P/E ratio of 8.79, below the industry average of 15.63 and its 5-year mean of 12.88. Reflecting these challenges, the Zacks Consensus Estimate for 2025 and 2026 earnings per share has seen slight downward revisions over the past 60 days.

Key Decisions for Investors

• Investors should closely monitor Gardasil's sales trajectory, particularly the resolution of inventory issues in China and demand trends in ex-China markets, given its significant impact on Merck's top line.
• Evaluate the market penetration and competitive positioning of the newly approved RSV antibody, Enflonsia, as its success will be crucial in offsetting the declining revenue from Gardasil and navigating a crowded therapeutic area.
• Consider Merck's current depressed valuation relative to its peers and historical levels as a potential entry point, but weigh this against the ongoing revenue pressures from Gardasil, heightened competition for new products, and the recent downward revisions in earnings estimates, warranting a cautious investment stance.