Pharmaceutical giant Sanofi to acquire vaccine biotech firm Vicebio for a potential value of $1.6 billion.
Sanofi, a leading global biopharmaceutical company, has announced its acquisition of Vicebio, a London-based biopharmaceutical firm specializing in next-generation respiratory virus vaccines. The deal, worth up to $1.6 billion, is a significant step forward for Sanofi as it seeks to expand its vaccine portfolio and focus on next-generation combination vaccines, particularly for protection against multiple respiratory viruses in vulnerable populations such as older adults.
The acquisition deal, officially announced on July 22, 2025, includes an upfront payment of $1.15 billion, with potential milestone payments of up to $450 million contingent on development and regulatory successes. The transaction is expected to close in the fourth quarter of 2025, subject to customary conditions and regulatory approvals.
Vicebio was initially backed by Medicxi and holds rights to the Molecular Clamp technology licensed from the University of Queensland. This technology stabilizes viral proteins in their native shape, improving immune response and facilitating efficient vaccine development and production. Vicebio’s lead asset, VXB-241, is a bivalent vaccine targeting Respiratory Syncytial Virus (RSV) and Human Metapneumovirus (hMPV), currently in early clinical testing.
Sanofi views this acquisition as a strategic expansion of its vaccine portfolio. Vicebio’s innovative technology and focus on developing vaccines against respiratory viruses like RSV, hMPV, Parainfluenza, Influenza, and Coronaviruses aligns well with Sanofi’s commitment to advancing public health prevention.
The Series B funding, led by TCGX and including investments from Goldman Sachs, Avoro Ventures, venBio Partners, UniQuest, and Medicxi, enabled Vicebio to accelerate its clinical development, including the successful completion of a Phase 1 trial of its bivalent RSV/hMPV vaccine in adults 60+.
Dr. Emmanuel Hanon, Vicebio’s CEO, expressed his enthusiasm about the acquisition, looking forward to combining Vicebio’s innovative technology with Sanofi’s global clinical development capability. Dr. Giovanni Mariggi, Chairman of Vicebio and Partner at Medicxi, shared similar sentiments, expressing excitement about partnering with Sanofi to accelerate the development of Vicebio’s multivalent vaccines.
Cariad Chester, Managing Partner at TCGX, praised Vicebio’s ambition to develop next-generation vaccines aimed at targeting multiple life-threatening respiratory viruses simultaneously. This acquisition is seen as a validation of Vicebio's ability to combine innovation and deep scientific expertise towards a common goal of advancing public health prevention.
Financially, the acquisition is not expected to have a significant impact on Sanofi’s financial guidance for 2025. Sanofi’s focus on respiratory viral vaccines and advanced vaccine technologies is underscored by this deal, which complements their R&D efforts powered by AI and immunology expertise.
In summary, the acquisition of Vicebio by Sanofi marks a strategic move in the development of next-generation respiratory virus vaccines. The deal is expected to close in the fourth quarter of 2025, pending approvals, and will further Sanofi’s commitment to advancing public health prevention.
[1] Sanofi Press Release, July 22, 2025. [2] Vicebio Press Release, July 22, 2025. [3] Market Report, July 2025. [4] Financial Times, July 23, 2025.
- This acquisition of Vicebio by Sanofi, valued at up to $1.6 billion, reflects Sanofi's focus on expanding its vaccine portfolio and investments in next-generation vaccines, particularly those targeting respiratory viruses.
- The deal, announced on July 22, 2025, includes an upfront payment of $1.15 billion with potential milestone payments of up to $450 million, further highlighting Sanofi's commitment to health-and-wellness and financing large-scale deals-and-discounts.
- Vicebio, with its innovative Molecular Clamp technology licensed from the University of Queensland, specializes in developing vaccines against respiratory viruses, such as RSV, hMPV, Parainfluenza, Influenza, and Coronaviruses, aligning perfectly with Sanofi's business strategies in science, research, and lifestyle sectors.
- This acquisition is expected to have minimal impact on Sanofi's 2025 financial guidance, demonstrating that investing in cutting-edge technologies and research aligns with maintaining financial stability, ultimately contributing to Sanofi's overall business success and achievements in the finance and lifestyle fields.
