Merck Rises 13% in a Week: Should You Buy, Sell or Hold the Stock?

Core Insights - Merck's shares have increased nearly 13% recently due to positive sentiment in the pharmaceutical sector following Pfizer's drug pricing deal with the Trump administration [1][4]. Drug Pricing and Market Impact - Pfizer will reduce prices of certain drugs to match those in comparable developed countries, supporting the Most Favored Nation pricing proposal [2]. - Pfizer will receive a three-year exemption from tariffs on pharmaceutical imports in exchange for increasing U.S. manufacturing investment, committing an additional $70 billion [3]. Merck's Strengths - Keytruda, Merck's leading drug, accounts for over 50% of its pharmaceutical sales and has driven steady revenue growth, with sales rising approximately 7% in the first half of 2025 [6][7]. - Merck is pursuing strategies to enhance Keytruda's long-term growth, including innovative combinations and a partnership with Moderna for a personalized mRNA cancer vaccine [8]. Pipeline and M&A Activity - Merck's phase III pipeline has nearly tripled since 2021, positioning the company to launch around 20 new vaccines and drugs in the coming years [10][11]. - The acquisition of Verona Pharma for approximately $10 billion will strengthen Merck's cardio-pulmonary pipeline [15]. Challenges and Sales Performance - Sales of the Gardasil vaccine have declined by 48% in the first half of 2025, primarily due to weak demand in China [16][17]. - Other vaccines and diabetes products are also experiencing declining sales, contributing to a challenging near-term outlook for Merck [18][32]. Patent Expiration and Competitive Pressure - Keytruda is set to lose patent exclusivity in 2028, raising concerns about Merck's reliance on this drug and its ability to grow its non-oncology business [19]. - Competitive pressure is expected to increase from new dual PD-1/VEGF inhibitors, which may challenge Keytruda's market position [20][21]. Valuation and Earnings Estimates - Merck's shares have underperformed the industry and the S&P 500, with a current price/earnings ratio of 9.41, lower than the industry average of 15.96 [22][25]. - Earnings estimates for 2025 have remained stable at $8.93 per share, while 2026 estimates have slightly declined [28]. Strategic Outlook - Despite challenges, Merck's new products are showing strong launches, and the approval of Keytruda Qlex may mitigate the impact of Keytruda's loss of exclusivity [30]. - A wait-and-see approach is recommended for investors, as the company navigates its current challenges and seeks sustainable growth [32].