Can Keytruda Sustain Merck's Growth Through the Rest of 2025?

Core Insights - Merck's oncology segment is significantly driven by Keytruda, which accounted for over 50% of the company's pharmaceutical sales in the first half of 2025 [1][11] - Keytruda generated $15.16 billion in sales during the first half of 2025, reflecting a year-over-year increase of nearly 7% [2][11] - The company anticipates continued growth from Keytruda, particularly in early-stage lung cancer, despite some offset from weaker Gardasil sales in China and Japan [4][3] Sales and Growth - Full-year 2025 sales for Keytruda are estimated to reach $32.2 billion, indicating a year-over-year growth of 9.2% [2] - The drug's sales are bolstered by its rapid adoption in early-stage non-small cell lung cancer and sustained momentum in metastatic indications [3] Strategic Initiatives - Merck is exploring various strategies for long-term growth, including innovative immuno-oncology combinations and a personalized mRNA therapeutic cancer vaccine in collaboration with Moderna [5][6] - A subcutaneous formulation of Keytruda is under review in the U.S., which could extend its patent life [7] Competitive Landscape - Competitive pressure for Keytruda may increase, particularly with Summit Therapeutics' ivonescimab showing promising results in a phase III study, potentially positioning it as a new standard of care [8] Financial Performance - Year-to-date, Merck's shares have decreased by 15.3%, underperforming both the industry and the S&P 500 [10] - The company's shares are currently trading at a price/earnings ratio of 9.01, which is lower than the industry average of 14.45 [12] Earnings Estimates - The Zacks Consensus Estimate for 2025 earnings has increased slightly from $8.85 to $8.92 per share, while the estimate for 2026 has decreased from $9.65 to $9.59 [13]