AstraZeneca’s Ultomiris expansion plan has hit a snag in the U.S.
Wednesday, AstraZeneca said the FDA handed the company a complete response letter for its Ultomiris application in neuromyelitis optica spectrum disorder (NMOSD), a rare autoimmune disease affecting the central nervous system.
The rejection didn’t raise concerns about the safety or efficacy of Ultomiris in its phase 3 NMOSD trial called CHAMPION-NMOSD nor did the FDA request additional analysis from the study, AZ said.
Instead, the regulator wants AstraZeneca to make modifications to its proposed Ultomiris Risk Evaluation and Mitigation Strategy (REMS). Specifically, the agency is asking the company to set up a system to confirm patients’ meningococcal vaccination status or prophylactic administration of antibiotics prior to treatment.
AstraZeneca says it’s working closely with the FDA on next steps for the REMS modifications and “remains committed to brining Ultomiris to people living with NMOSD in the U.S. as quickly as possible.”
Ultomiris is already cleared to treat certain adults with NMOSD in places such as the EU and Japan.
In the U.S., the drug is approved to treat generalized myasthenia gravis in certain adults, plus certain adults and children with paroxysmal nocturnal hemoglobinuria or atypical hemolytic uremic syndrome.
Ultomiris proved its worth in NMOSD back in May 2022. Compared with the placebo arm in a clinical trial of its predecessor Soliris, Ultomiris reduced the risk of relapse in NMOSD patients who tested positive for anti-AQP4 antibodies.
About three-quarters of NMOSD patients are positive for the AQP4 biomarker. In the U.S., that represents about a 4,500 target population for Ultomiris, according to a previous estimate by AZ’s Alexion.
Soliris, for its part, won its NMOSD go-ahead from the FDA in 2019 based on data from the phase 3 PREVENT trial. In that study, 94 of the 96 patients (98%) who took Soliris were relapse-free at 48 weeks, compared with 30 of 47 patients (63%) in the placebo group.
In the first half of 2023, Ultomiris brought home (PDF) $1.36 billion compared to Soliris’ $1.65 billion.