
Ahead of FDA, EMA recommends authorizing new gene therapy treatment for ultra-rare disease
Aromatic amino acid decarboxylase (AADC) deficiency is an ultra-rare genetic disease that leaves patients unable to produce certain hormones in the brain, such as dopamine and serotonin, usually leading to developmental delays, weak muscle tone and inability to control the movement of the limbs. It can also lead to multiple organ failure.
To date, there have been no treatments approved for AADC deficiency, which has been identified in less than 150 patients.
But now, New Jersey biotech PTC Therapeutics is one step closer to getting its gene therapy approved in the EU. The European Medicines Agency announced earlier today that it would recommend granting a marketing authorization for the one-time gene therapy Upstaza, giving it the “exceptional circumstances” moniker.
That moniker is given to a type of marketing authorization granted to medicines where the applicant is “unable to provide comprehensive data on the efficacy and safety under normal conditions of use, because the condition to be treated is rare or because collection of full information is not possible or is unethical,” according to the EMA.
Data come from three trials that had enrolled a combined 28 children. The main favorable effects attained by the participants in the study were head control and the ability to sit unassisted, the EMA said, adding that consultants agreed that meaningful efficacy was demonstrated in the trials
The agency’s CHMP committee also has asked PTC to submit data showing both long-term efficacy and safety in patients enrolled in clinical trials based on a 10-year follow up and a global registry-based safety study. In the meantime, another EMA committee, the Committee for Advanced Therapies, said that the benefits of Upstaza outweigh the possible risks in patients with AADC deficiency. The most common side effects were elevated body temperature and involuntary, erratic movements, known as dyskinesia.
After an authorization is granted — PTC said in a statement it was expecting a decision in approximately two months — the next big question that EU member states and PTC will face is the price. Gene therapies, especially ones promoted to be a one-treatment cure, have shown to be extremely costly. Novartis’s Zolgensma, a gene therapy for a specific type of spinal muscular atrophy, owns the dubious distinction of most expensive drug in the world, costing between $1.8 million and $2.1 million per patient.