Dynavax Acquired by Sanofi — Healthcare M&A

Sanofi has completed its acquisition of Dynavax Technologies Corporation, bringing the US-listed biopharma into Sanofi’s portfolio through a merger structure. The transaction includes Dynavax’s adult hepatitis B vaccine HEPLISAV-B, marketed in the US, and its shingles vaccine candidate Z-1018, currently in phase 1/2 studies, along with additional vaccine pipeline projects. The deal was implemented via a tender offer for all outstanding Dynavax shares, followed by a statutory merger in which Dynavax became a surviving corporation and an indirect wholly owned subsidiary of Sanofi. Dynavax common stock ceased trading on Nasdaq Global Select on completion.

The acquisition strengthens Sanofi’s adult immunization franchise by combining Dynavax’s vaccine assets with Sanofi’s commercial reach, global scale, and development capabilities. HEPLISAV-B is positioned around a differentiated two-dose regimen over one month, while Z-1018 adds to Sanofi’s pipeline in shingles. Strategically, the move reflects continued consolidation in healthcare and vaccines as large pharmaceutical companies seek to expand late-stage and early-stage immunization offerings.

Under the tender offer, Sanofi offered $15.50 per share in cash, and shares not validly tendered were converted into the same $15.50 per share cash consideration, subject to applicable withholding taxes. The tender offer expired on February 9, 2026, and Sanofi accepted and paid for validly tendered shares before completing the merger on February 10, 2026. Deal size was not disclosed.