FDA approves MPS VII drug

The U.S. Food and Drug Administration today approved Mepsevii (vestronidase alfa-vjbk) to treat pediatric and adult patients with MPS VII, Sly syndrome.

The safety and efficacy of Mepsevii, developed by Ultragenyx, were established in clinical trial and were tested on 23 patients ranging from 5 months to 25 years of age. Patients received treatment with Mepsevii at doses up to 4 mg/kg once every two weeks for up to 164 weeks.

Patients were given a six-minute walk test to measure efficacy, and after 24 weeks of treatment, subjects on the treatment regimen improved by about 60 feet. After 120 weeks, there was improvement in three patients and stabilization in the others. Two patients in the Mepsevii development program experienced marked improvement in pulmonary function. Overall, the results observed would not have been anticipated in the absence of treatment. The effect of Mepsevii on the central nervous system manifestations of MPS VII has not been determined.

The FDA granted this application Fast Track designation, which seeks to expedite the development and review of drugs that are intended to treat serious conditions where initial evidence showed the potential to address an unmet medical need. Mepsevii also received Orphan Drug designation, which provides incentives to assist and encourage the development of drugs for rare diseases.

For more information, please visit Ultragenyx’s website.