Ultomiris Approved in Japan as Treatment for AChR-Positive gMG
The therapy's mechanism of action is similar to that of Soliris, but is longer lasting
The approval covers adults positive for antibodies against the acetylcholine receptor (AChR) — the most common type of MG-driving autoantibody — and who either don’t respond adequately to intravenous immunoglobulin (IVIG) or plasma exchange, or aren’t eligible for these first-line treatments.
“The approval of Ultomiris is an important advance for the gMG community in Japan, offering patients and physicians a new long-acting C5 inhibitor that has demonstrated sustained improvement in activities of daily living through 60 weeks, with fewer infusions per year over current treatment,” Hiroyuki Murai, MD, PhD, a professor at the International University of Health and Welfare in Narita, Japan, said in a press release.
Ultomiris is designed to bind to the C5 protein, blocking the activation of the complement cascade — a group of inflammatory proteins that play a central role in the autoimmune attack that causes MG.
This mechanism of action is nearly identical to that of a previously approved MG therapy called Soliris (eculizumab), but Ultomiris was engineered to last longer in the body, thus allowing for less frequent dosing. Both Ultomiris and Soliris were developed by Alexion Pharmaceuticals, now part of AstraZeneca.
Ultomiris was approved for AChR-positive gMG by the U.S. Food and Drug Administration earlier this year. It recently received a positive recommendation from a regulatory committee favoring approval in the EU.
Its approval in Japan was supported by data from the Phase 3 CHAMPION-MG clinical trial (NCT03920293), during which 175 adults with gMG were randomized to receive Ultomiris or a placebo for 26 weeks (about half a year). Participants, none of whom had previously been on a C5 inhibitor, could then enter into an open-label extension where all were given Ultomiris.
Results showed Ultomiris rapidly eased gMG symptoms and improved quality of life compared with the placebo, with benefits lasting for more than a year of treatment. The most common side effects of it were headache, nausea, and diarrhea.
“The approval speaks to the strength and consistency of Ultomiris clinical data as demonstrated in the global CHAMPION-MG Phase III trial,” Marc Dunoyer, CEO of Alexion, said. “We are pleased that Ultomiris is now approved in Japan for adults with gMG, a disease that may impact their ability to work, meet family obligations and live their lives fully. We look forward to bringing this treatment option to people living with gMG in Japan as part of our broader strategy to expand global access to our medicines.”