Ultragenyx sets $3.95 million U.S. price for rare disease gene therapy

Sept 17 (Reuters) - Ultragenyx Pharmaceutical announced on Thursday a U.S. list price of $3.95 million for its newly approved gene therapy Fayuvi, bringing to market one of the world's costliest medicines as a one-time treatment for a rare and fatal childhood disease.

The U.S. Food and Drug Administration approved Fayuvi for pediatric patients with Sanfilippo syndrome Type A, an inherited condition that gradually damages the brain and nervous system.

The disease is caused by a deficiency in an enzyme called sulfamidase, which leads to abnormal accumulation of a complex sugar molecule known as heparan sulfate in the body and brain. This toxic buildup causes children to progressively lose cognitive, speech, and motor skills.

Ultragenyx executives said on a conference call that the lifetime cost of caring for a child with the disease, who can spend years bedridden, may exceed $8 million, a burden they said grows as the disease advances.

J.P. Morgan analysts estimate Fayuvi could achieve peak worldwide sales of $200 million to $250 million.

Shares of Ultragenyx ended Thursday up 12.6%.

Given through a single intravenous infusion, the gene therapy introduces a functional copy of the SGSH gene into cells so the body can produce sulfamidase and clear away the harmful accumulation.

According to the FDA, children who received the therapy in trials either preserved or improved their cognitive function when compared with untreated patients.

Glenn O’Neill, president and co-founder of the nonprofit Cure Sanfilippo Foundation, said the approval offers 'real hope and a real life-changing chance to have a different outcome than the traditional course of this disease.' His daughter Eliza was diagnosed in 2013 and received the therapy in 2016 at age 6.

Before the decision, Eliza's parents told Reuters that she has 'never had a seizure' and does not rely on a feeding tube or wheelchair; she attends school and swims, outcomes they said far surpass what is usual for the disease.

Ultragenyx anticipates that Fayuvi will be accessible at specialized treatment centers in the U.S. within 30 to 60 days.