Press Release: Sanofi completes the acquisition of Dynavax

Press Release
Sanofi completes the acquisition of Dynavax

Paris, February 10, 2026. Sanofi today announced that it has completed the acquisition of Dynavax Technologies Corporation (Dynavax). The acquisition includes Dynavax’s adult hepatitis B vaccine HEPLISAV-B, which is currently marketed in the US and is differentiated by its two-dose regimen over one month. It also includes Dynavax’s shingles vaccine candidate (Z-1018), which is currently in phase 1/2 studies, and additional vaccine pipeline projects.

This acquisition augments Sanofi’s presence in adult immunization by bringing together Dynavax’s vaccines with Sanofi’s commercial reach, global scale, and development capabilities.

The tender offer for all outstanding shares of Dynavax common stock, par value $0.001 per share expired one minute after 11:59 P.M. EST, on February 9, 2026. The minimum condition and all the other conditions to the offer have been satisfied, and on February 10, 2026, Sanofi accepted for payment and will promptly pay for all shares validly tendered and not validly withdrawn.

Following its acceptance of the tendered shares, Sanofi completed its acquisition of Dynavax through the merger of a wholly owned subsidiary of Sanofi with and into Dynavax, pursuant to Section 251(h) of the General Corporation Law of the State of Delaware, with Dynavax continuing as the surviving corporation and becoming an indirect, wholly owned subsidiary of Sanofi. In connection with the merger, all Dynavax shares not validly tendered in the tender offer have been converted into the right to receive the same $15.50 per share in cash, without interest, subject to any applicable withholding taxes, that would have been paid had such shares been validly tendered in the tender offer. As of February 10, 2026, Dynavax common stock will cease to be traded on the NASDAQ Global Select Stock Market.

About Sanofi

Sanofi is an R&D driven, AI-powered biopharma company committed to improving people's lives and delivering compelling growth. We apply our deep understanding of the immune system to invent medicines and vaccines that treat and protect millions of people around the world, with an innovative pipeline that could benefit millions more. Our team is guided by one purpose: we chase the miracles of science to improve people's lives; this inspires us to drive progress and deliver positive impact for our people and the communities we serve, by addressing the most urgent healthcare, environmental, and societal challenges of our time. Sanofi is listed on EURONEXT: SAN and NASDAQ: SNY

Media Relations

Sandrine Guendoul | +33 6 25 09 14 25 | sandrine.guendoul@sanofi.com
Evan Berland | +1 215 432 0234 | evan.berland@sanofi.com
Léo Le Bourhis | +33 6 75 06 43 81 | leo.lebourhis@sanofi.com
Victor Rouault | +1 617 356 4751 | victor.rouault@sanofi.com
Timothy Gilbert | +1 516 521 2929 | timothy.gilbert@sanofi.com
Léa Ubaldi | +33 6 30 19 66 46 | lea.ubaldi@sanofi.com
Ekaterina Pesheva | +1 410 926 6780 | ekaterina.pesheva@sanofi.com

Investor Relations

Thomas Kudsk Larsen | +44 7545 513 693 | thomas.larsen@sanofi.com
Alizé Kaisserian | +33 6 47 04 12 11 | alize.kaisserian@sanofi.com
Keita Browne | +1 781 249 1766 | keita.browne@sanofi.com
Nathalie Pham | +33 7 85 93 30 17 | nathalie.pham@sanofi.com
Nina Goworek | +1 908 569 7086 | nina.goworek@sanofi.com
Thibaud Châtelet | +33 6 80 80 89 90 | thibaud.chatelet@sanofi.com
Yun Li | +33 6 84 00 90 72 | yun.li3@sanofi.com

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