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# Alexion BLA Approved for Ultomiris in Rare Disease
- URL: https://www.fdaweb.com/alexion-bla-approved-for-ultomiris-in-rare-disease/
- Published: 2019-10-21T12:00:00.000Z
- Updated: 2026-09-15T01:57:57.000Z
- Author: David McFarland
- Tags: Biologics, #legacy-id-D5145300

FDA has approved an Alexion Pharmaceuticals BLA for Ultomiris (ravulizumab-cwvz) for treating atypical hemolytic uremic syndrome (aHUS) to inhibit complement-mediated thrombotic microangiopathy (TMA) for adult and pediatric patients. The ultra-rare disease can cause progressive injury to vital organs, primarily the kidneys, by damaging walls of blood vessels. Approval was based on [data](https://cts.businesswire.com/ct/CT?id=smartlink&url=https%3A%2F%2Fnews.alexion.com%2Fpress-release%2Fproduct-news%2Falexion-announces-positive-top-line-results-phase-3-study-ultomiris-ravul&esheet=52101009&newsitemid=20191018005600&lan=en-US&anchor=data&index=2&md5=e2cebb761e809c3cbc245c2fbee2fb10&ref=fdaweb.com) from two global, single-arm open-label studies of Ultomiris – one in adults and one in children – with aHUS. The pediatric study is ongoing and a total of 14 out of 16 children were enrolled and included in the interim analysis.

In the initial 26-week treatment periods, 54% of adults and 71% (interim data) of children demonstrated a complete TMA response, the company says. The therapy was also shown to reduce thrombocytopenia (low blood platelet count) in 84% of adults and 93% of children, it says. Additionally, it reduced hemolysis in 77% of adults and 86% of children, and improved kidney function in 59% of adults and 79% of children (for patients on dialysis at enrollment.