Swedish drugmaker Sobi agreed to acquire Arthrosi Therapeutics, paying $950 million upfront plus up to $550 million in milestone payments, the company announced. Arthrosi’s lead candidate is a Phase 3 therapy for gout; the deal secures a late‑stage pipeline asset for Sobi and adds potential near‑term commercial upside if pivotal data and regulatory filings succeed. Sobi framed the transaction as strategic inorganic growth to expand its rare and specialty inflammatory disease franchise. The structure of upfront and contingent payments implies Sobi is balancing near‑term cash deployment with outcome‑linked risk sharing for clinical and regulatory readouts.