Written By: Pharmacally Medical News Desk
Sanofi has agreed to acquire Dynavax Technologies Corporation in an all-cash transaction valued at approximately $2.2 billion, marking a strategic push to expand its adult immunization portfolio. The deal brings a marketed hepatitis B vaccine and an early-stage shingles program into Sanofi’s global vaccines business.
The acquisition adds HEPLISAV-B, Dynavax’s adult hepatitis B vaccine, which is already marketed in the US, EU, and UK. HEPLISAV-B stands out for its two-dose schedule given over one month, compared with traditional three-dose regimens spread over six months, allowing faster and higher rates of seroprotection in adults.
Sanofi will also gain Dynavax’s shingles vaccine candidate Z-1018, currently in Phase 1/2 development, along with additional early pipeline assets. Together, these programs broaden Sanofi’s reach beyond pediatric vaccines and reinforce its focus on adult and aging populations.
Adult vaccination remains an underpenetrated area, particularly for hepatitis B and shingles. In the US alone, nearly 100 million adults born before 1991 remain unvaccinated against hepatitis B. Chronic hepatitis B infection can progress to cirrhosis and liver cancer. Shingles, caused by reactivation of the varicella-zoster virus, affects roughly one in three adults during their lifetime and can lead to long-term nerve pain and serious complications.
Sanofi expects Dynavax’s assets to benefit from its global development, manufacturing, and commercial scale, accelerating access and uptake in key markets.
Sanofi will launch a cash tender offer to acquire all outstanding Dynavax shares at $15.50 per share, representing a total equity value of about $2.2 billion. The transaction has been unanimously approved by Dynavax’s board and is subject to customary regulatory and shareholder conditions. Sanofi plans to fund the acquisition with existing cash and does not expect any impact on its 2025 financial guidance. Closing is anticipated in the first quarter of 2026.
With this acquisition, Sanofi strengthens its adult vaccine franchise by adding a differentiated, revenue-generating hepatitis B vaccine and a promising shingles candidate. The move underscores a broader industry shift toward addressing unmet needs in adult and lifelong immunization, an area likely to see sustained public health and commercial relevance.
Sanofi said the acquisition strengthens its adult immunization strategy by adding differentiated vaccines that complement its existing vaccine expertise, expanding options for hepatitis B prevention, and advancing its shingles pipeline across the adult lifespan.
Dynavax noted that joining Sanofi provides the global scale, development strength, and commercial reach needed to fully realize the potential of HEPLISAV-B and its broader vaccine pipeline, helping address important public health needs while delivering value to shareholders.
Dynavax Technologies Corporation is a US-based commercial-stage biopharmaceutical company focused on the discovery, development, and commercialization of innovative vaccines for infectious diseases. Dynavax has an established commercial footprint through its marketed hepatitis B vaccine, HEPLISAV-B, and has built a pipeline centered on applying its adjuvant platform to next-generation vaccines.
Reference
Press Release: Sanofi to acquire Dynavax, adding a marketed adult hepatitis B vaccine and phase 1/2 shingles candidate to the pipeline, 24 December 2024, https://www.sanofi.com/en/media-room/press-releases/2025/2025-12-24-06-15-00-3210241