Sanofi Expands Respiratory Vaccine Portfolio with $1.6B Vicebio Acquisition

Sanofi has announced a significant expansion of its respiratory vaccine pipeline through the acquisition of UK-based biotech Vicebio for up to $1.6 billion. The deal, which includes a $1.15 billion upfront payment and potential milestone payments of $450 million, centers around Vicebio's innovative combination vaccine programs targeting respiratory syncytial virus (RSV) and other respiratory pathogens.

Vicebio's Combination Vaccine Pipeline

At the heart of the acquisition is VXB-241, a bivalent vaccine candidate targeting both RSV and human metapneumovirus (hMPV). The vaccine, which recently completed a Phase Ib study involving over 150 healthy volunteers, utilizes Vicebio's proprietary Molecular Clamp platform. This technology stabilizes viruses in their natural shape, potentially enhancing immune response and simplifying manufacturing and distribution processes.

Vicebio's pipeline also includes a more advanced combination vaccine targeting RSV, hMPV, and parainfluenza virus Type 3 (PIV3), scheduled to enter Phase I trials in the third quarter of this year. Additionally, the company is developing an avian flu vaccine slated for Phase I development in the second quarter of 2026.

Strategic Fit with Sanofi's Respiratory Portfolio

The acquisition complements Sanofi's existing position in the respiratory vaccine space, which includes the RSV immunizing antibody Beyfortus, approved for use in newborns and infants up to 24 months of age. Beyfortus generated $1.77 billion in revenue last year.

Thomas Triomphe, Executive Vice President of Sanofi Vaccines, stated, "This acquisition allows us to offer increased physician and patient choice by adding a non-mRNA vaccine candidate to our pipeline of RSV programs."

Sanofi's Ongoing M&A Strategy

The Vicebio deal is the latest in a series of acquisitions by Sanofi this year, reflecting the company's aggressive business development strategy. Notable recent transactions include:

• A $600 million upfront payment for Dren Bio's bispecific antibody DR-0201 in March
• The $470 million acquisition of Vigil Neuroscience and its Alzheimer's disease therapy VG-3927 in May
• A potential $9.5 billion deal to acquire Blueprint Medicines in June

François-Xavier Roger, Chief Financial Officer at Sanofi, recently indicated that the company retains "significant capacity for further business development, particularly in early-stage medicines and vaccines."