Merck Pill Threatens Injectables in $3B Cholesterol Market
Oral PCSK9 inhibitor matches efficacy of shots, putting pressure on Amgen and Regeneron
Merck has developed an oral cholesterol-lowering pill that achieved a 64.6% reduction in LDL cholesterol in clinical studies, matching the efficacy of injectable drugs that currently dominate a market worth more than $3 billion annually. The breakthrough threatens to disrupt the duopoly held by Amgen's Repatha and Regeneron's Praluent, which have controlled roughly 70% of global PCSK9 inhibitor revenues through injectable formulations requiring biweekly or monthly administration.
The global PCSK9 inhibitor market is estimated at $3.14 billion to $3.24 billion in 2025 and projected to grow to $3.5 billion to $3.92 billion in 2026, representing a compound annual growth rate of approximately 17% to 21%. Amgen's Repatha generated over $3 billion in annual sales during 2025, with fourth-quarter revenue surging 44% year-over-year to $870 million. Repatha has maintained the largest market share among PCSK9 inhibitors, controlling approximately 52.4% of the market.
Regeneron and Sanofi's Praluent, which co-markets the drug outside the United States, recorded $739 million in sales during 2024. In the fourth quarter of 2025, Praluent sales outside the U.S. reached €132 million (approximately $143 million), contributing to increased collaboration revenue for both companies. The drug captured roughly 30% of the U.S. market by 2018 and has remained a significant competitor in the cholesterol treatment space.
The emergence of Merck's enlicitide decanoate, the first oral PCSK9 inhibitor to demonstrate efficacy comparable to injectables, could fundamentally alter patient preferences and prescribing patterns. Oral medications typically offer greater convenience and lower administration costs than biologics requiring injection. If the oral formulation successfully completes clinical development and regulatory review, insurers may push patients toward the less expensive option, potentially compressing pricing power for existing injectable therapies.
Both Amgen and Regeneron face significant exposure to this competitive threat. Amgen has identified Repatha as a key growth driver for 2026, though the company anticipates a mid-single-digit decline in the drug's net selling price. Regeneron's collaboration revenue from Praluent has been increasing, driven by higher profits from antibody commercialization. Any market share losses or pricing pressure from oral competition could impact these revenue streams.
The PCSK9 inhibitor market is already experiencing competitive pressure from Novartis's Leqvio (inclisiran), an RNA-interference therapeutic requiring only twice-yearly dosing. Leqvio was the fastest-growing therapy for Novartis in 2023-2024, with revenue growth of 112%. The arrival of an effective oral option would add another dimension to the increasingly competitive landscape for cholesterol-lowering treatments.
Market analysts will be watching for details on Merck's clinical development timeline, potential regulatory pathways, and pricing strategy for the oral PCSK9 inhibitor. The transition from injectable biologics to oral small molecules represents a significant challenge for established players, who may need to accelerate their own oral development programs or prepare defensive strategies to maintain market position in the evolving cholesterol treatment landscape.