The FDA recently approved a new infused therapy, Xenpozyme (olipudase-alfa) from Genzyme , for pediatric and adult patients with Acid Sphingomyelinase Deficiency (ASMD), a rare genetic disease that causes premature death. Xenpozyme is the first approved medication to treat symptoms that are not related to the central nervous system in patients with ASMD.
ASMD is caused by the lack of an enzyme needed to break down a complex lipid, called sphingomyelin, that accumulates in the liver, spleen, lung, and brain. Patients with ASMD have enlarged abdomens that can cause pain, vomiting, feeding difficulties, and falls. They also have abnormal liver and blood tests. The most severely affected patients have profound neurologic symptoms and rarely survive beyond two to three years of age. Other patients may survive into adulthood but die prematurely from respiratory failure.
The U.S. list price of Xenpozyme is $7,142.00 per vial. Xenpozyme comes with a complicated, weight-based dose escalation schedule – biweekly for the first 14 weeks and then bi-weekly thereafter upon sustaining the recommended full dose (see prescribing information).
Xenpozyme is supplied in a 20 mg vial and one may guesstimate that 26 vials (biweekly) will be utilized during a year resulting in an annual cost of approx. $185,000.
No details were announced relating to distribution. Given its cost and the need to monitor patient response it may be likely that this ‘rare’ therapy will launch through specialty pharmacy distribution.