Novel gene therapy improves outcomes in children with rare neurometabolic disorder
PTC Therapeutics Inc. released results of a 5-year analysis that showed its novel gene therapy, PTC-AADC, improved outcomes among children with aromatic L-amino acid decarboxylase deficiency.
The rare neurometabolic disorder affects the central nervous system and inhibits the body’s production of the dopamine required for normal development and functioning. Currently, no approved disease-modifying therapies exist for aromatic L-amino acid decarboxylase (AADC) deficiency.
"The transformations we are seeing in the children are remarkable, as they could not even lift their heads before treatment," Stuart W. Peltz, PhD, CEO of PTC Therapeutics, said in a press release. "Treatment with PTC-AADC is restoring dopamine production, which leads to the children now being able to sit, roll over, stand and walk.
“They are also able to communicate and gain both weight and strength,” Peltz added. “We believe these results show its potential as a transformational therapy for the AADC patients and their families."
The results showed sustained improvements in motor function, which suggested durability of PTC-AADC’s treatment effect. Data across three clinical trials showed improvements in motor development among all children from as early as 3 months. Children showed significant improvement from baseline in cognitive and language skills according to Bayley III scores, with the ability to understand their caregivers and express themselves.
Moreover, results showed a decline in the rate of respiratory infection from an average of 2.4 episodes per year at 1 year to 0.6 episodes per year at 2 years and 0.3 episode per year at 5 years. Most treated children exhibited age-appropriate weight gain by 1 year after gene therapy treatment after having had a baseline weight below the third percentile.
PTC-AADC is an investigational new drug in the U.S., with a biologics license application expected to be submitted to the FDA by the end of the year.
"The impact that this one-time gene therapy has had on children with AADC deficiency in these trials is truly life-changing," investigator Paul Wuh-Liang Hwu, of the National Taiwan University Hospital, said in the release. "We are encouraged by the strong safety profile and long-lasting effect seen with PTC-AADC, and how it has improved the lives of patients and their caregivers."