New information from clinical trials on Pompe disease

The 10th French Pompe disease Day took place on 28 January 2021 by videoconferencing. It brought together over 80 experts, and provided the opportunity not only to review the consequences of the health crisis on patient care, but also to provide an overview of the various trials currently underway or in preparation in France. Although the pandemic and resulting confinement have had adverse consequences on the follow-up of patients with Pompe disease (temporary discontinuation of enzyme therapy treatment and physiotherapy, reduced physical activity), research remains very active.


Results of the PROPEL trial announced

The PROPEL trial is evaluating the efficacy and safety of AT-GAA, a next generation enzyme (cipaglucosidase alfa or ATB200) in combination with a chaperone molecule (miglustat or AT2221) in the late-onset form of Pompe disease. Over a one-year period, 117 adults received either Myozyme® or AT-GAA. They are now participating in an extension phase of the trial that is scheduled to continue until 2023.

Amicus Therapeutics, the company that is developing AT-GAA, announced the preliminary results of the PROPEL trial on 11 February 2021.

  • The primary endpoint for the study, the 6-minute walk test, did not demonstrate the superiority of the drug candidate over Myozyme®
  • However, in respiratory terms, vital capacity remained fairly stable over the one-year period in the group treated with AT-GAA (-0.9%), while it decreased (-4%) in the Myozyme® group.
  • Both treatments are well tolerated.

Amicus Therapeutics plans to submit marketing authorisation application dossiers in the United States and Europe during the course of 2021.


NeoGAA trials are continuing

Avalglucosidase alfa (neoGAA) is another next generation enzyme therapy developed by Sanofi Genzyme, the company that is already marketing Myozyme®. It is being evaluated in the early-onset forms of the disease by the COMET trial, and in the neonatal forms by the miniCOMET trial. Preliminary results of the COMET trial favour neoGAA over Myozyme®: it seems to be better tolerated and slightly more effective.


Start of the Spark Therapeutics gene therapy trial

Several gene therapy approaches are being studied in Pompe disease. Spark Therapeutics has just started an international trial to evaluate the safety, tolerability and efficacy of SPK-3006 in the late-onset form of the disease. French centres should be taking part in this trial.

SPK-3006 is based on a technique developed at Généthon that brings the missing GAA gene to the liver cells. It facilitates the continuous production of a form of GAA that is well-tolerated by the body


Access Amicus Therapeutics press release (2021-02-11) Amicus’ AT-GAA Shows Clinically Meaningful & Significant Improvements in Both Musculoskeletal and Respiratory Measures in Late-Onset Pompe Disease Compared to Standard of Care in Pivotal Phase 3 PROPEL Study (


Access Spark Therapeutics press release (2021-02-01) Spark Therapeutics Announces First Participant Dosed in Phase 1/2 Study of Investigational Gene Therapy for Late-Onset Pompe Disease (