BREAKING: Merck & Co. has just announced its acquisition of Cidara Therapeutics for approximately $9.2 billion, a strategic move aimed at enhancing its antiviral pipeline. This urgent development comes as Merck seeks to expand its offerings, particularly with the promising Phase III drug, CD388, designed to prevent influenza in high-risk individuals.
The acquisition deal is set to provide Merck access to CD388, a long-acting antiviral that has shown potential for universal prevention of seasonal and pandemic influenza. This drug is currently being tested in the Phase III ANCHOR trial, which involves 6,000 participants at 150 sites across the United States and the United Kingdom. The trial specifically targets adults and adolescents who are at an increased risk of severe complications from influenza.
Merck’s Chairman and CEO, Robert M. Davis, expressed confidence in the acquisition, stating, “We intend to build on the Cidara team’s remarkable progress and are confident that CD388 has the potential to be another important driver of growth through the next decade.”
This announcement follows Cidara’s successful results from its Phase IIb NAVIGATE trial, which demonstrated significant efficacy in preventing symptomatic influenza among healthy, unvaccinated adults. With prevention efficacy ranging from 57.7% to 76.1% depending on the dosage, CD388 presents a compelling alternative to existing vaccines and antiviral treatments.
Cidara’s President and CEO, Jeffrey Stein, highlighted the importance of this acquisition, stating, “Merck’s global development, regulatory and commercial capabilities provide the expertise and resources needed to bring this important innovation to those individuals who need it most.” The partnership aims to address unmet needs in influenza prevention, particularly as flu seasons become increasingly severe.
The deal, which offers Cidara shareholders $221.50 per share in cash—a significant 109% premium to the company’s previous closing price—has already resulted in a remarkable 105% surge in Cidara’s share price, closing at $217.71 on the NASDAQ. Merck’s shares remained stable at $92.93 on the New York Stock Exchange on the day of the announcement.
This acquisition is part of Merck’s broader strategy to counteract impending revenue losses as several key products, including the blockbuster cancer drug Keytruda®, face patent expirations in the coming years. As Merck navigates this “patent cliff,” it remains focused on expanding its portfolio with innovative treatments.
The acquisition is anticipated to close in the first quarter of 2026, pending regulatory approvals. This transformative moment for Cidara underscores the urgency of advancing new therapeutic options in the fight against influenza.
As the pharmaceutical landscape evolves, eyes will be on the outcomes of the ANCHOR trial and the future growth potential of Merck’s enhanced antiviral pipeline. Stay tuned for updates on this developing story that impacts public health and the pharmaceutical industry.
