Harbour BioMed has taken the lead in the Chinese leg of a competitive autoimmune race, becoming the first company to show an anti-FcRn drug improves outcomes in generalized myasthenia gravis (gMG) in the country. The result is a boost for Immunovant, which has rights to the drug in several major markets.
The drug candidate, batoclimab, is one of a clutch of anti-FcRn molecules in development in gMG and a number of other diseases. Argenx is leading the way in the West, having won approval for Vyvgart in the U.S. and the EU, and companies including Johnson & Johnson and UCB are giving chase. In China, Harbour’s anti-FcRn monoclonal antibody has a shot at beating its rivals to market.
Monday, the biopharma released an update on its phase 3 trial of batoclimab in 132 gMG patients. Harbour is yet to share data from the study, saying only that it met its primary and key secondary endpoints and showed batoclimab is safe and efficacious.
“Anti-FcRn treatment has received much attention in patients with gMG, and batoclimab is the first anti-FcRn treatment confirmed efficacious and safe in [the] Chinese gMG population,” said Chongbo Zhao, M.D., the trial's principal investigator. “The pivotal clinical success sets a monumental milestone for the development of new drugs and further reinforces the position of FcRn antagonists in the treatment of MG.”
Harbour secured breakthrough status for batoclimab from the Chinese drug regulatory agency in 2021 and formed a co-development pact covering the country with CSPC NBP Pharmaceutical late last year. NBP Pharma will commercialize batoclimab in greater China.
While Harbour’s phase 3 success gives NBP Pharma a shot at beating its FcRn rivals to market in China, batoclimab faces more advanced competition in the U.S. and the EU. Immunovant began a phase 3 trial of the drug candidate in gMG last year, putting it around one year behind J&J’s nipocalimab and further still away from UCB’s near-approval rozanolixizumab and argenx’s authorized Vyvgart.
The level of competition reflects the belief that FcRn drugs can rack up the sort of blockbuster sales seen in the anti-TNF space. J&J bet $6.5 billion on that belief when it bought Momenta Pharmaceuticals to get its hands on nipocalimab. This year, J&J will start to find out whether its big bet will pay off, with phase 3 data in gMG and midstage results in rheumatoid arthritis scheduled for publication.