Overview
- Sanofi agreed to acquire Dynavax for $15.50 per share in cash, valuing the deal at about $2.2 billion through a tender offer targeted to close in the first quarter of 2026.
- The acquisition adds HEPLISAV-B, an approved adult hepatitis B vaccine that uses a two-dose, one-month schedule delivering faster seroprotection than traditional three-dose regimens.
- The deal also brings Z-1018, a shingles vaccine candidate in phase 1/2 development, positioning Sanofi for potential entry into a market led by GSK’s Shingrix.
- Dynavax shares jumped roughly 37% to 40% on the news as Sanofi said it would use available cash for the purchase and affirmed no impact to 2025 guidance.
- Closing remains subject to a majority tender and regulatory clearances including HSR review, while Sanofi separately reported an FDA complete response letter for tolebrutinib and related follow-up actions.