Myrtelle Receives Rare Pediatric Disease Designation for Canavan Disease Gene Therapy

Myrtelle said that the U.S. Food and Drug Administration granted Fast Track, Rare Pediatric Disease, and Orphan Drug designations for its lead clinical-stage gene therapy, rAAV-Olig001-ASPA, for the treatment of patients with the fatal childhood brain disease Canavan Disease.

Canavan disease (CD) is a genetic condition in which mutations in the aspartoacylase gene (ASPA) prevent the normal expression of aspartoacylase, a critical enzyme produced in oligodendrocytes that breaks down the neurochemical N-Acetylaspartate (NAA). When not properly metabolized by oligodendrocytes, NAA accumulates in the brain and negatively affects bioenergetics, myelin production, and brain health.

CD patients are impacted at birth but may appear normal until several months old when symptoms begin to develop. Poor head control, abnormally large head size, difficulty in eye tracking, excessive irritability, severely diminished muscle tone, and delays in reaching motor milestones, such as rolling, sitting, and walking, are the typical initial manifestations of CD. As the disease progresses, seizures, spasticity, difficulties in swallowing, and overall muscle deterioration emerge with most affected children developing life-threatening complications by 10 years of age. Currently, there are no cures for CD and only palliative treatments are available.

Myrtelle’s rAAV-Olig001-ASPA uses a novel proprietary recombinant adeno-associated virus that for the first time directly targets oligodendrocytes in the brain. Oligodendrocytes are the cells in the brain responsible for producing myelin, the insulating material that enables proper function of neurons. The production of myelin is affected in CD due to mutations in the aspartoacylase gene coding for the aspartoacylase enzyme. The oligodendrocyte-targeted gene therapy is intended to restore ASPA function, enable metabolism of the abundant brain chemical NAA, and support myelination.

“FDA’s decision to grant these designations for our investigational gene therapy utilizing rAAV-Olig001-ASPA aligns with our mission to provide treatments for patients where few if any options exist and highlights the urgency of developing a treatment for patients with Canavan disease, a devastating disease of young children which results in short life expectancy,” said Nancy Barone Kribbs, senior vice president of regulatory affairs at Myrtelle.

Myrtelle is conducting an ongoing phase 1/2 first-in-human clinical trial of rAAV-Olig001-ASPA. It has also entered into an exclusive worldwide licensing agreement with Pfizer in 2021 to develop and commercialize this novel gene therapy for the treatment of CD.

The FDA grants Rare Pediatric Disease designation for serious and life-threatening diseases that primarily affect children aged 18 years or younger and impact fewer than 200,000 people in the United States. If a New Drug Application in the United States for rAAV-Olig001-ASPA is approved, Myrtelle may be eligible to receive a Priority Review Voucher from the FDA.

The vouchers can be used to reduce the time of an FDA new drug approval review to six months from ten months. The vouchers are potentially lucrative because they are transferable. Most recently, BioMarin Pharmaceutical sold its voucher for $110 million.

Author: Rare Daily Staff