Incyte (Nasdaq: INCY) has completed its acquisition of Vega Therapeutics, Inc., a wholly owned subsidiary of San Francisco-based Star Therapeutics LLC, adding a Phase III monoclonal antibody for von Willebrand disease to its hematology portfolio in a deal valued at up to USD 2.0 billion. The US-based acquirer, headquartered in Wilmington, Delaware, gains global rights to VGA039 through the transaction, which extends its hematology franchise beyond myeloproliferative neoplasms into inherited bleeding disorders.
Under the terms of the stock purchase agreement, announced in June 2026, Incyte paid USD 1.25 billion upfront for all outstanding shares of Vega Therapeutics. Star Therapeutics is eligible to receive up to USD 750 million in additional payments contingent solely on the achievement of sales milestones; no development or regulatory milestone tranches were disclosed. The transaction is structured as an equity acquisition and is expected to generate an R&D charge of approximately USD 1.25 billion in Incyte's Q3 and full-year 2026 GAAP and non-GAAP financial results. No royalty terms were disclosed.
VGA039 targets Protein S, a vitamin K-dependent plasma glycoprotein that normally suppresses coagulation, through a dual mechanism: promoting platelet attachment and enhancing fibrin deposition to restore hemostasis. By modulating Protein S rather than directly replacing deficient von Willebrand factor, the antibody operates independently of VWD subtype, giving it potential applicability across all forms of the disease. VGA039 has received Breakthrough Therapy, Fast Track, orphan drug, and rare pediatric disease designations from the US FDA and has advanced into the Phase III VIVID-6 study (NCT07115004), a global, single-arm crossover trial evaluating subcutaneous VGA039 as prophylaxis across all VWD types. If approved, it would be the first once-monthly subcutaneous prophylactic option for VWD patients who currently depend on two to three intravenous infusions per week of factor replacement therapies.
The competitive landscape for late-stage VWD prophylaxis is developing. Denmark-based Hemab Therapeutics raised USD 346.7 million via a Nasdaq IPO to advance HMB-002, a subcutaneous monoclonal antibody in Phase I/II for VWD prophylaxis, reflecting investor interest in the space and the earlier development stage of competing programs relative to VGA039.