Biogen entered a definitive agreement with TJ Biopharma to acquire exclusive Greater China rights to felzartamab, a CD38-directed monoclonal antibody in development across immune-mediated conditions. The deal is valued at up to $850 million, including a $100 million upfront payment and additional milestone payments tied to commercial performance. Biogen will consolidate global development and commercialization control for felzartamab, following prior rights arrangements that excluded Greater China. The agreement also reflects the continuation of a collaboration that began in April 2025, with TJ Biopharma participating in Biogen-led Phase III trials for IgA nephropathy and primary membranous nephropathy. For companies with international portfolios, the transaction highlights how rights consolidation is increasingly used to reduce regional execution friction—especially in China where competitive development dynamics require local strategy alignment.