Sanofi has struck a deal to buy Vicebio for $1.15 billion upfront, securing preclinical and phase 1 vaccine candidates to expand its respiratory syncytial virus (RSV) pipeline beyond mRNA.
The French drugmaker markets the anti-RSV antibody Beyfortus with AstraZeneca and has a pipeline of mRNA and live attenuated vaccines against the pathogen. Sanofi said buying Vicebio will enable it to “offer increased physician and patient choice” by adding a non-mRNA vaccine candidate to its pipeline of RSV programs. The deal follows the appointment of mRNA critics to a federal vaccine advisory panel.
London-based Vicebio’s most advanced prospect is VXB-241, a bivalent vaccine candidate targeting RSV and human metapneumovirus (hMPV). The company started a phase 1 trial of VXB-241 in healthy adults aged 60 to 83 last year.
Vicebio developed the vaccine using technology that stabilizes viral glycoproteins in their native shape. Sanofi believes the technology will enhance the immune response to the glycoproteins and simplify the production and distribution of the vaccines. Vicebio has identified the technology as a way to generate vaccines that provide protection against multiple pathogens in a single jab.
The biotech’s preclinical vaccine candidate, VXB-251, targets RSV, hMPV and parainfluenza virus Type 3 (PIV3). Sanofi already has mRNA vaccines against the three pathogens in the clinic. SP0256 targets RSV and hMPV. SP0291 targets RSV, hMPV and PIV3. Those candidates are for older adults. Sanofi has a live attenuated RSV vaccine for toddlers in phase 3.
RSV, hMPV and PIV3 all cause lower respiratory tract infections such as pneumonia. The viruses cause similar symptoms, such as cough and fever, and can circulate at the same time. The overlaps have fueled interest in vaccines that protect against two or more of the pathogens.
Moderna lists a vaccine against RSV and hMPV in its phase 1 pipeline, but the biotech stopped work on an hMPV-PIV3 candidate back in 2023. Clover Biopharmaceuticals recently started phase 1 trials of two vaccines that could compete with Sanofi’s assets, one against RSV and hMPV and another against RSV, hMPV and PIV3.
Sanofi expects to close the Vicebio takeover in the fourth quarter. The deal includes up to $450 million in development and regulatory milestones on top of the $1.15 billion upfront fee. Vicebio raised a $100 million series B round last year.
The deal comes weeks after Sanofi agreed to buy Blueprint Medicines for $9.1 billion. At the time, François-Xavier Roger, chief financial officer at Sanofi, told investors the company retained “significant capacity for further business development, particularly in early-stage medicines and vaccines.”