Sanofi is boosting its vaccine portfolio and pipeline by way of the acquisition of Dynavax Applied sciences, a $2.2 billion deal bringing belongings that might give the corporate aggressive benefits over merchandise marketed by rival vaccines maker GSK.
The acquisition phrases introduced Wednesday name for Sanofi to pay $15.50 in money for every share of Dynavax, representing a 39% premium to the inventory’s Tuesday closing worth. When Emeryville, California-based Dynavax went public in 2004, it priced its shares at $7.50 apiece.
Heplisav B, a hepatitis B vaccine authorized within the U.S. and Europe for adults, is Dynavax’s sole commercialized product. This vaccine is run as two intramuscular injections one month aside. Against this, GSK’s Engerix-B, a hepatitis B vaccine, and Twinrix, which protects in opposition to each hepatitis A and B, are each administered in a three-shot routine throughout six months. Dynavax contends its vaccine permits a affected person to realize excessive ranges of protecting antibodies sooner than different vaccines and with an identical security profile.
Dynavax reported $268.4 million in Heplisav B gross sales in 2024, a 26% improve in comparison with the prior yr. In its report of third quarter 2025 monetary outcomes, the corporate mentioned it estimates this product elevated its share of the hepatitis B vaccines market to 46%, up from 44% in 2024.
Sanofi’s presence in hepatitis B vaccines covers solely youngsters. Vaxelis, commercialized beneath a partnership with Merck, protects in opposition to hepatitis B and 5 different pathogens. The 2023 FDA approval of Vaxelis, given in a three-shot collection over six month, covers its use in youngsters from age 6 weeks by way of 4 years outdated.
The Dynavax pipeline consists of the shingles vaccine candidate Z-1018. In August, the corporate reported encouraging preliminary knowledge from an early-stage research that examined this vaccine face to face in opposition to Shingrix, the GSK product that at present dominates the shingles vaccine market. Dynavax mentioned its shingles vaccine was nicely tolerated, displaying decrease native and systemic post-injection reactions in comparison with Shingrix. Sturdy immune responses had been reported in any respect doses, together with the dose chosen to advance to the second a part of the Section 1/2 research; preliminary knowledge are anticipated within the second half of 2026.
“Dynavax enhances Sanofi’s grownup immunization presence by including differentiated vaccines that complement Sanofi’s experience,” Thomas Triomphe, Sanofi’s govt vp, vaccines, mentioned in a ready assertion. “Its marketed grownup hepatitis B vaccine and shingles candidate convey new choices to our portfolio and underscore our dedication to offering vaccine safety throughout the lifespan.”
The acquisition announcement comes as hepatitis B vaccines face better regulatory scrutiny from the Trump administration. In early December, the Advisory Committee on Immunization Practices (ACIP), a panel that makes vaccine suggestions to the Facilities for Illness Management and Prevention, voted to suggest shared resolution making for hepatitis B vaccination for youngsters. That’s a weaker suggestion than the ACIP’s decades-old suggestion that these vaccinations begin at start.
To William Blair analyst Matt Phipps, the acquisition is sensible for Dynavax given rising regulatory considerations round vaccines and investor questions on administration’s technique for worth creation. It additionally is sensible for Sanofi.
“Sanofi is a logical acquisition associate for Dynavax given the corporate has intensive vaccine capabilities however the portfolio doesn’t have an grownup hepatitis B or shingles program,” Phipps mentioned in a analysis observe.
Apart from the shingles vaccine candidate, the Dynavax pipeline features a plague vaccine in growth beneath a partnership with the U.S. Division of Protection in addition to wholly owned clinical-stage packages for pandemic influenza and Lyme illness. In November, Dynavax licensed international rights to Vaxart’s oral Covid-19 vaccine candidate, at present in mid-stage testing. Per deal phrases, Dynavax paid $25 million up entrance and made a $5 million fairness funding in Vaxart.
Dynavax is Sanofi’s second vaccines M&A deal this yr. In July, the pharmaceutical large agreed to pay $1.15 billion to purchase Vicebio, a startup whose lead program is a bivalent vaccine in early-stage growth for respiratory syncytial virus (RSV) and human metapneumovirus (hMPV).
Sanofi mentioned it can finance the Dynavax acquisition with obtainable money assets. The Dynavax board of administrators has authorized the deal, which nonetheless requires a majority of shareholders to tender their shares. The transaction is predicted to shut within the first quarter of 2026.
Picture: Francesco Carta fotografo, Getty Photos
