Sanofi agreed to license ADEL’s tau‑targeting antibody ADEL‑Y01 in a deal worth up to $1.04 billion, including an $80 million up‑front payment, ADEL and Sanofi disclosed. The agreement grants Sanofi global rights outside of certain retained territories and moves a U.S. phase I Alzheimer’s candidate into Sanofi’s neurology development engine. ADEL’s program targets acetylated tau species; Sanofi will take responsibility for late‑stage development, regulatory filings, and commercialization. ADEL retained tiered royalties and development‑linked payments. The transaction adds to a wave of year‑end biobucks deals as big pharma targets neurodegeneration candidates to replenish pipelines. The companies said near‑term activities will focus on bridging studies and manufacturing scale‑up ahead of multi‑site trials.