Sanofi has completed its $2.2-billion acquisition of Dynavax Technologies, a vaccines company. The deal was announced in January 2026. 

Dynavax’s key product is its adult hepatitis B vaccine, Heplisav-B, which is marketed in the US and is differentiated by a two-dose regimen over one month. This dosing enables high levels of seroprotection faster than other hepatitis B vaccines, which are given in three doses over six months, according to the company. The acquisition also includes Dynavax’s shingles vaccine candidate (Z-1018), which is currently in Phase I/II clinical development and additional vaccine pipeline projects. 

Sanofi completed its acquisition of Dynavax through the merger of a wholly owned subsidiary of Sanofi with and into Dynavax, with Dynavax continuing as the surviving corporation and becoming an indirect, wholly owned subsidiary of Sanofi. 

Source: Sanofi