Rahway-based Merck on Friday announced it signed a definitive agreement to acquire San Diego-based Cidara Therapeutics, Inc. for approximately $9.2 billion in an all-cash transaction. The acquisition is a strategic move by the New Jersey pharmaceutical giant to significantly diversify and expand its respiratory portfolio and pipeline, particularly in the critical area of influenza prevention.
The deal centers on Cidara’s lead candidate, CD388, an investigational long-acting, strain-agnostic antiviral agent currently in Phase 3 clinical trials. CD388 is designed to prevent influenza A and B infection in individuals who are at a higher risk of complications from the flu, such as older adults and immunocompromised patients.
Merck, which recently wrapped up a $10 billion acquisition of Verona Pharma, continues to execute a science-led business development strategy to secure new revenue drivers ahead of the impending patent cliff for its blockbuster cancer drug, Keytruda.
Robert Davis, chairman and CEO of Merck, affirmed the importance of the deal from the New Jersey headquarters, stating, “We continue to execute our science-led business development strategy, augmenting our pipeline with CD388, a potentially first-in-class, long-acting antiviral… We are confident that CD388 has the potential to be another important driver of growth through the next decade, creating real value for shareholders.”
The acquisition underscores Merck’s commitment to investing in innovative therapies to address global health threats. Influenza, which CD388 targets, is estimated to cause between 290,000 and 650,000 deaths globally each year.
CD388 has already received Breakthrough Therapy Designation and Fast Track Designation from the U.S. Food and Drug Administration (FDA) following positive results from its Phase 2b study. The compound is unique in that it consists of a small molecule neuraminidase inhibitor combined with a proprietary fragment of a human antibody, making it potentially effective regardless of a patient’s specific immune status.
Merck’s substantial global development, regulatory, and commercial capabilities, based in New Jersey and across its worldwide network, are expected to accelerate the development and potential launch of the new antiviral. The transaction has been approved by both companies’ boards and is anticipated to close in the first quarter of 2026.
This deal complements the multi-billion dollar investments Merck is already making in its New Jersey operations, including a planned $3.5 billion investment in its Rahway headquarters expected to create approximately 1,000 jobs across research and clinical manufacturing.
