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Oct 18 (Reuters) - The U.S. Food and Drug Administration on Friday approved Alexion Pharmaceuticals Inc's treatment for a second rare blood disorder, the company said.
The treatment, Ultomiris, has already been approved in the United States, Japan and the European Union to treat adults with blood disorder called paroxysmal nocturnal hemoglobinuria.
Friday's approval allows its use in treating atypical hemolytic uremic syndrome (aHUS), a condition that causes abnormal blood clots to form in small blood vessels in the kidneys, which could result in kidney failure.
The label for the treatment carries a boxed warning, the FDA's harshest, flagging risks of life-threatening meningococcal infections or sepsis, that have occurred in patients treated with Ultomiris.
The FDA approval is a shot in the arm for the drugmaker, which has been pushing to expand Ultomiris' label as U.S. market exclusivity for its best-selling drug, Soliris, is being threatened. The drugmaker is pushing to convert patients to Ultomiris, which is considered a successor drug.
Analysts say that Ultomiris is also a more convenient option as it needs to be infused only every eight weeks, compared to every two weeks for those on Soliris.
It is also slightly more potent than Soliris, Cowen analyst Phil Nadeau said.
Patients administered Ultomiris will be given an initial loading dose, followed by maintenance every eight weeks depending on their body weight.
Ultomiris has a list price of $6,404 per vial, compared with $6,543 per vial for Soliris, which accounts for more than 80% of Alexion's total sales.
On average, the annual cost for Ultomiris maintenance doses is about $458,000, a discount of about 33% to the labeled maintenance dose of Soliris in aHUS, Alexion noted.
The list price of a drug is not necessarily what patients actually pay. Out-of-pocket costs vary based on an individual's healthcare plan and the duration of treatment.
Ultomiris is expected to bring in sales of about $1.5 billion by 2024 for its use in aHUS, Nadeau said.
Alexion is pushing to maintain its leadership in treating certain rare blood disorders and earlier this week agreed to buy smaller biotech Achillion Pharmaceuticals Inc for $930 million. That follows two acquisitions last year that added to its pipeline of rare disease drugs.
The company is also testing Ultomiris for use in patients with autoimmune disease neuromyelitis optica spectrum disorder and generalized myasthenia gravis. (Reporting by Manojna Maddipatla and Trisha Roy in Bengaluru; Additional reporting by Sanjana Shivdas in Bengaluru; Editing by Daniel Wallis)