The FDA has granted Breakthrough Therapy designation to asfotase alfa for the treatment of patients with hypophosphatasia (HPP), according to Alexion Pharma International, a global pharmaceutical company based in Cheshire, Conn.

HPP is an inherited, life-threatening, ultra-rare metabolic disorder that leads to progressive damage to multiple vital organs, including destruction and deformity of bones. Asfotase alfa, an investigational, targeted enzyme replacement therapy, aims to treat patients with HPP whose first signs or symptoms occurred prior to 18 years of age, including perinatal-, infantile-, and juvenile-onset forms of the disease.

"The FDA's Breakthrough Therapy designation for perinatal-, infantile- and juvenile-onset HPP recognizes the severe, debilitating and life-threatening nature of the disease, the clear unmet medical need of patients, and the clinical evidence collected to date on asfotase alfa," said Martin Mackay, Ph.D., executive vice president, global head of R&D at Alexion. "Asfotase alfa is a highly innovative therapeutic candidate with the potential to transform the lives of patients with HPP who currently have no treatment options and often receive only palliative care for this life-threatening disease."

Alexion looks forward to working closely with the FDA and obtaining FDA guidance on the subsequent development of asfotase alfa for the treatment of HPP, including obtaining advice on generating evidence needed to support approval of the drug in an efficient manner.

The FDA also confirmed that adult-onset HPP is "a serious and life threatening disease or condition" and that Breakthrough Therapy designation could be obtained for this aspect of the disease with additional clinical information.