Amicus Therapeutics Reports Positive Long-Term Data of Pompe Therapy

Rare Daily Staff

Amicus Therapeutics reported positive results from the global phase 3 open-label extension study to investigate the long-term efficacy and safety of its experimental AT-GAA therapy in adult patients with late-onset Pompe disease, an inherited lysosomal disorder.

Study participants treated with AT-GAA for up to 104 weeks showed persistent and durable effects on six-minute walk distance (6MWD), stability in forced vital capacity (FVC), and continued reductions in biomarkers of muscle damage and disease substrate. The results are being featured at the 19th Annual WORLDSymposium 2023 in a poster presentation and an oral platform presentation.

Pompe disease is caused by a deficiency of the enzyme acid alpha-glucosidase (GAA). Reduced or absent levels of GAA lead to accumulation of glycogen in cells, which is believed to result in the clinical manifestations of Pompe disease. Pompe disease ranges from a rapidly fatal infantile form with significant impacts to heart function, to a more slowly progressive, late-onset form primarily affecting skeletal muscle and progressive respiratory involvement. Late-onset Pompe disease can be severe and debilitating, including progressive muscle weakness throughout the body, particularly the skeletal muscles and muscles controlling breathing that worsens over time.

AT-GAA is a two-component therapy that consists of cipaglucosidase alfa, a bis-M6P-enriched rhGAA which facilitates high-affinity uptake through the M6P receptor while retaining its capacity for processing into the most active form of the enzyme, and the oral enzyme stabilizer, miglustat, which is designed to minimize loss of enzyme activity in the blood. In clinical studies, AT-GAA was associated with demonstrated improvements in both musculoskeletal and respiratory measures.

“These open label extension data from our phase 3 PROPEL study of AT-GAA continue to represent meaningful and durable improvements in functional outcomes, as well as persistent reductions in key biomarkers of muscle damage and disease substrate out to two years,” said Bradley Campbell, president and CEO of Amicus. “These results give great hope that AT-GAA has the potential to become the new global standard of care for people living with Pompe disease.”

Photo: Bradley Campbell, president and CEO of Amicus