The US Food and Drug Administration has approved a self administered once daily autoinjector for Zilbrysq (zilucoplan), UCB announced on October 16. The device gives adults with generalised myasthenia gravis who are anti acetylcholine receptor antibody positive a second way to take the complement C5 inhibitor at home, alongside the prefilled syringe sold since the drug’s original approval in October 2023. UCB expects commercial availability in the first quarter of 2027.
The approval rests on device data, not new efficacy trials. A Phase 1 crossover study in 14 healthy volunteers established bioequivalence between autoinjector and syringe. In the Phase 3b DV0013 study, 31 adults with the disease self administered by autoinjector, with complete dose delivery in 99.8 percent of 449 uses and injection site pain, in 3 patients (9.7 percent), as the most common treatment emergent adverse event. In a separate human factors study of 100 participants, 90 percent completed an injection successfully on the first attempt without training.
UCB’s framing is adherence. “As the first treatment to be approved as a once-daily autoinjector option for adults living with gMG in the U.S., ZILBRYSQ now provides the same therapy via another administration option,” said Kimberly Moran, the company’s head of US rare diseases. The drug keeps its boxed warning for serious meningococcal infections and its restricted REMS distribution, unchanged by the new device.
The commercial context is portfolio depth rather than expansion. UCB also markets Rystiggo, an FcRn antibody for the same disease with a different mechanism, so the autoinjector widens the convenience argument around an installed therapy instead of opening a new one. Device approvals of this kind rarely move a franchise on their own; they defend it, one daily injection at a time.