MSD acquires Cidara Therapeutics for USD9.2B to strengthen influenza prevention pipeline

USA—Merck Sharp & Dohme (MSD) has agreed to acquire Cidara Therapeutics in a USD9.2 billion deal that brings a promising long-lasting influenza prevention drug into its portfolio.

The pharmaceutical giant will pay USD221.50 per share in cash to purchase the US biotech company, which has developed an innovative platform called drug-Fc conjugates (DFCs).

Cidara’s technology creates molecules with extended half-lives that work without triggering an immune response.

This approach differs fundamentally from traditional vaccines, which depend on the body’s immune system to provide protection.

The biotech’s lead product, CD388, combines a small molecule neuraminidase inhibitor with an Fc fragment of a human antibody to prevent both influenza A and B infections.

Speaking to Pharmaceutical Technology in October, Cidara CEO Jeff Stein explained how the company transformed a potent enzyme inhibitor with poor drug properties into an effective treatment with excellent characteristics.

The resulting product requires administration just once per flu season, offering significant practical advantages over existing options.

CD388 currently undergoes evaluation in the Phase III ANCHOR study involving adult and adolescent participants at higher risk of developing influenza complications.

The antiviral already demonstrated success in the Phase IIb NAVIGATE study, earning breakthrough therapy designation from the US Food and Drug Administration.

Dr. Dean Li, president of MSD Research Laboratories, noted that the acquisition expands and complements the company’s respiratory portfolio and pipeline.

For MSD, buying Cidara opens a strong growth opportunity in the infectious disease sector, particularly significant given the current volatility surrounding vaccines in the US market.

MSD CEO Robert Davis expressed confidence that CD388 has the potential to drive substantial growth throughout the next decade while creating real value for shareholders.

The company intends to build on Cidara’s progress and advance the product toward commercialization.

The US government has already recognized Cidara’s potential, awarding the biotech USD339 million through the Biomedical Advanced Research and Development Authority.

This federal funding will support domestic manufacturing of CD388 and help establish an initial supply chain for commercialization.

CD388’s long-lasting nature offers several advantages over traditional vaccines in fighting seasonal influenza.

Stein highlighted that the drug eliminates the need to modify manufacturing processes annually in response to changing influenza strains, making it more economically feasible to stockpile for national preparedness.

This acquisition marks MSD’s second billion-dollar deal in 2025, following the USD10 billion purchase of cardio-pulmonary specialist Verona Pharmaceuticals in July.

The company continues strengthening its pipeline as the patent expiration approaches for Keytruda, its blockbuster cancer drug.