Changchun GeneScience Pharmaceutical Co., Ltd.

GenSci Partners with RTW Investments in $1.365 Billion Deal for First-in-Class Thyroid Autoimmune Disease Therapy

- GenSci and RTW Investments announced a strategic partnership granting Yarrow Bioscience exclusive global ex-China rights to develop GS-098 (YB-101), a first-in-class anti-TSHR antibody for Graves' disease and thyroid eye disease. - The deal includes a $70 million upfront payment and potential milestone payments totaling up to $1.365 billion, with GenSci retaining development and commercialization rights in China. - YB-101 represents a novel targeted approach that selectively blocks thyroid-stimulating autoantibodies without systemic immunosuppression, addressing significant unmet medical needs in autoimmune thyroid disorders. - Yarrow plans to advance YB-101 into a U.S.-based Phase 1b/2b trial for Graves' disease in the first half of 2026, with Phase 1b data expected in the second half of 2027.