Biogen Pays up to $850m for Felzartamab Rights in China to Challenge Darzalex
Biogen acquired exclusive rights to felzartamab in Greater China for up to $850m, gaining control of a China BLA submission for r/r MM. Felzartamab’s 1.5-hour infusion and domestic production could capture 14.6% of China’s $458m MM market by 2029, challenging Darzalex’s 87.5% share.
1. Deal Terms
On April 20, Biogen agreed to pay up to $850m for exclusive rights to TJ Biopharma’s anti-CD38 immunotherapy felzartamab in the Greater China region, securing the registrational BLA for relapsed and refractory multiple myeloma and retaining manufacturing at TJ’s Hangzhou GMP facility.
2. Competitive Landscape
Janssen’s Darzalex dominates with an 87.5% share of the $7.6bn global anti-CD38 market and requires up to seven-hour intravenous infusions, while felzartamab offers a 1.5-hour administration. Janssen’s subcutaneous Darzalex Faspro, currently in China trials, could heighten competition by enabling rapid, home-based dosing.
3. Market Outlook
In 2025, 35.8% of r/r MM patients across eight major markets received anti-CD38 treatment. With strong government incentives for domestic production, felzartamab is projected to attain 14.6% of China’s $458m MM market by 2029, testing Biogen’s ability to win prescriber trust and challenge the incumbent.