Ultomiris secures Priority Review in the US for treatment of adults with immunoglobulin A nephropathy

The US FDA has accepted and granted Priority Review status to Alexion, AstraZeneca Rare Disease’s supplemental Biologics License Application for Ultomiris, targeting the treatment of adults living with immunoglobulin A nephropathy.

Priority Review is reserved by the FDA for applications involving medicines that, upon approval, would represent a meaningful step forward compared to existing treatment options, whether through gains in safety or efficacy, prevention of serious health conditions, or better patient adherence. A decision under the Prescription Drug User Fee Act is expected to arrive during the final quarter of 2026.

IgAN is a rare condition marked by inflammation of the kidneys that can progress toward chronic kidney disease and, eventually, end-stage kidney disease. The disease originates when the body produces abnormal IgA proteins, forming immune complexes that settle within the kidneys and cause harm. This deposition triggers activation of the complement system, setting off terminal complement-driven inflammation that damages and destroys essential kidney structures, including the glomeruli responsible for filtering the blood. As this damage accumulates, kidney function gradually deteriorates. In the US alone, more than 217,000 people currently live with an IgAN diagnosis.

“Despite available treatments, people living with IgAN often progress to end-stage kidney disease, underscoring the urgent need for new disease-modifying approaches. Building on our pioneering leadership in complement science, this Priority Review reflects the strength of the interim analysis data from the I CAN trial and the potential of Ultomiris as the first C5 complement inhibitor to address terminal complement-driven inflammation in IgAN,” said Marc Dunoyer, Chief Executive Officer, Alexion.

The application is grounded in findings from a prespecified interim analysis of the I CAN Phase III trial, shared recently at the 2026 European Renal Association Congress.

Within the trial, Ultomiris produced a 46.6% reduction in 24 hour urine protein creatinine ratio from baseline by week 34, compared to a 5.6% reduction among those given placebo, translating into a placebo-adjusted treatment effect of 43.4%.

This drop in proteinuria came on quickly, with a 36.7% reduction already evident by week 10 among those on Ultomiris, compared to 8.5% in the placebo arm, and the effect held steady through week 34. The pattern remained consistent across patient subgroups representing a wide range of demographic backgrounds, baseline clinical features, and disease severity. The trial’s primary endpoint, tracking change in estimated glomerular filtration rate from baseline, is set to be measured at week 106.

Throughout the I CAN trial, the safety profile of Ultomiris remained consistent with what has previously been established, with the treatment generally well tolerated and no new safety concerns emerging.

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Related Topics and Keywords

immunoglobulin A nephropathy, Ultomiris