Group 1 - Sanofi announced an agreement to acquire Dynavax Technologies for approximately $2.2 billion in cash, with the deal approved by Dynavax's board [1] - The acquisition price is set at $15.50 per share, representing a 39% premium over Dynavax's closing price of $11.13 on December 23 [1] - The transaction is expected to be completed in the first quarter of 2026 and will be funded using Sanofi's existing cash reserves, with no impact on its 2025 financial performance [1] Group 2 - This acquisition marks Sanofi's second vaccine-related purchase in 2025, following the $1.5 billion acquisition of UK biotech company Vicebio and a potential $9.5 billion deal for BluePrint Medicines [2] - The move aims to diversify Sanofi's business and reduce reliance on its flagship asthma drug Dupixent [2] - The backdrop of this acquisition includes significant changes in U.S. vaccine policy, with criticism from U.S. Health Secretary Robert Kennedy leading to budget cuts for vaccine research and changes in CDC leadership [2]

Group 1 - Sanofi has agreed to acquire Denali Therapeutics for approximately $2.2 billion to expand its vaccine product line focused on influenza vaccines [1] - The acquisition will be at a cash price of $15.50 per share, representing a 39% premium over Denali's closing price on Tuesday [1] - This acquisition will provide Sanofi with an already marketed hepatitis B vaccine and an experimental shingles vaccine currently in early human trials, enhancing its presence in the adult vaccination market [1] Group 2 - Sanofi emphasized that the acquisition is not expected to impact its financial guidance for 2025 and is anticipated to be completed in the first quarter of 2026 [1] - Shortly before announcing the acquisition, Sanofi disclosed that its investigational multiple sclerosis drug tolebrutinib faced a rejection from the FDA [2] - The R&D head of Sanofi expressed disappointment regarding the FDA's decision, noting a significant and substantive shift in direction compared to previous feedback from the agency [3]