Ultragenyx Pharmaceutical to Apply to Feds for Expanded Use of a Key Drug

Novato-based rare disease drug maker Ultragenyx Pharmaceutical Inc. (Nasdaq: RARE) announced Tuesday it is collaborating with Japanese firm Kyowa Kirin to apply for expanded use of one of its drugs, Crysvita.

Also called burosumab, the drug is used to treat X-linked hypophosphataemia, a hereditary disorder characterized by low levels of phosphate in the blood. Phosphate is needed to build and maintain strong bones and teeth and to maintain their strength.

On Tuesday Ultragenyx announced plans to submit a supplemental biologics license application (sBLA) to the U.S. Food and Drug Administration for Crysvita for the treatment some types of tumor-induced osteomalacia or TIO.

Osteomalacia is a softening of the bones than can be caused by inadequate levels of available phosphate, calcium and vitamin D.

“Based on productive discussions with the FDA, we will be moving forward expeditiously with an sBLA filing for Crysvita in tumor-induced osteomalacia,” said Camille L. Bedrosian, M.D., chief medical officer of Ultragenyx, in a statement. “We look forward to working with the agency during the review process, and we are committed to getting this therapy to patients with this serious disease with significant unmet medical need.”

The statement from Ultragenyx noted the submission of the Crysvita sBLA is planned for the first half of 2020.

According to the release, Crysvita is approved by the U.S. FDA, Health Canada, and Brazil’s National Health Surveillance Agency for the treatment of XLH in adult and pediatric patients one year of age and older, and has received European conditional marketing authorization for the treatment of XLH with radiographic evidence of bone disease in children one year of age and older and adolescents with growing skeletons.

XLH is a rare disease with an estimated prevalence of 3,000 pediatric and 9,000 adult patients in the U.S. according to Ultragenyx’s website.

The company reported a loss of $99.2 million in its second quarter last month although its revenues were up 94%. Ultragenyx noted a strong showing from the launch of Crysvita in a statement released along with its earnings report.