AstraZeneca's Ultomiris Wins FDA Accelerated Approval as First C5 Inhibitor for IgA Nephropathy

The U.S. FDA on Wednesday granted accelerated approval to AstraZeneca's (AZN) Ultomiris, developed by subsidiary Alexion, to reduce proteinuria in adults with primary immunoglobulin A nephropathy (IgAN) at risk of disease progression. The decision makes ravulizumab the first and only C5 complement inhibitor approved for this indication. The approval followed Priority Review and was based on a prespecified interim analysis of the Phase III I CAN trial. At week 34, Ultomiris reduced the 24-hour urine protein creatinine ratio by 46.6% from baseline versus 5.6% for placebo, a placebo-adjusted reduction of 43.4% (95% CI: 33.5%, 51.8%; p<0.0001). Proteinuria reduction appeared as early as week 10 and was sustained through week 34, with a consistent effect across patient subgroups. No new safety concerns were identified. AstraZeneca noted it has not been established whether Ultomiris slows kidney function decline in IgAN; continued approval may depend on confirming clinical benefit via estimated glomerular filtration rate at week 106 in the ongoing trial. This marks Ultomiris's fifth indication, administered intravenously every eight weeks after a loading dose. Submissions are under review in Japan and other countries, with late-breaking results slated for presentation at the American Society of Nephrology's Kidney Week on October 23, 2026. AZN closed at $168.45, down 0.22%.