Incyte agreed to buy Vega Therapeutics for $1.25 billion upfront, adding Vega’s Phase 3 monoclonal antibody VGA-039 as a potential new growth driver in von Willebrand disease (VWD). The deal includes up to $750 million in sales milestones and positions VGA-039 as a candidate for subcutaneous prophylaxis, which could reduce reliance on frequent intravenous factor replacement. Vega’s therapy works by modulating Protein S to improve hemostasis. Incyte said VGA-039 has multiple FDA designations, including breakthrough therapy, fast track, orphan drug, and rare pediatric disease status. Incyte expects closing in the third quarter of 2026, subject to conditions. The acquisition arrives as patent expiration risk looms for Incyte’s Jakafi franchise, sharpening the focus on building a post-peak hematology portfolio. The Vega purchase also reflects how late-stage development in smaller hematology markets is attracting larger strategic bids when differentiated convenience and mechanism-of-action are clear.