Alexion’s Ultomiris wins FDA Priority Review in IgA nephropathy

Rare Daily Staff

The U.S. Food and Drug Administration granted Alexion, AstraZeneca’s rare disease unit, Priority Review for Ultomiris for adults with immunoglobulin A nephropathy (IgAN), marking a potential regulatory milestone for a disease with limited treatment options.

The agency is expected to deliver its decision in the fourth quarter of 2026 under the Prescription Drug User Fee Act timeline. Priority Review status is granted to therapies that may offer significant improvements in safety or efficacy over existing treatments.

The supplemental biologics license application (sBLA) is supported by interim Phase III data from the global I CAN trial, which showed that Ultomiris reduced proteinuria—a key marker of kidney damage—by 43.4 percent compared with placebo at 34 weeks. Proteinuria reduction was observed as early as 10 weeks and sustained through the study period.

IgA nephropathy is a chronic, immune-mediated kidney disease driven by the deposition of abnormal IgA immune complexes in the kidneys, triggering complement activation and inflammation. The disease can progress to end-stage kidney disease, with roughly half of at-risk patients developing kidney failure within a decade of diagnosis.

Ultomiris targets the C5 protein in the terminal complement cascade, a pathway increasingly implicated in IgAN pathogenesis. If approved, it would become the first therapy in this class for the disease, extending Alexion’s established complement franchise into nephrology.

The safety profile observed in the trial was consistent with prior studies of Ultomiris, with no new safety signals identified.

The I CAN study is ongoing, with final data expected to evaluate long-term kidney function outcomes, including changes in estimated glomerular filtration rate (eGFR) at 106 weeks. While proteinuria reduction is considered an important surrogate endpoint, regulators will also weigh longer-term renal outcomes in their assessment.

Ultomiris is already approved across multiple indications, including paroxysmal nocturnal hemoglobinuria, atypical hemolytic uremic syndrome, generalized myasthenia gravis, and neuromyelitis optica spectrum disorder.

The Priority Review decision places Ultomiris among a growing group of late-stage therapies targeting complement and immune pathways in IgAN, an increasingly competitive space as developers seek disease-modifying approaches beyond supportive care.

“Despite available treatments, people living with IgAN often progress to end-stage kidney disease, underscoring the urgent need for new disease-modifying approaches,” said Marc Dunoyer, CEO of Alexion. “This Priority Review reflects the strength of the interim analysis data and the potential of Ultomiris as the first C5 complement inhibitor to address terminal complement-driven inflammation in IgAN.”

Photo: Marc Dunoyer, CEO of Alexion