AT2220 Co-Administered with Enzyme Replacement Therapy
Second Phase 2 Pharmacological Chaperone-ERT Co-Administration Study

CRANBURY, NJ, US, December 1, 2011 – Amicus Therapeutics, a biopharmaceutical company at the forefront of developing therapies for rare diseases, today announced the initial infusion of the first subject in an open-label Phase 2 drug-drug interaction study (Study 010) of AT2220 (duvoglustat HCl) co-administered with enzyme replacement therapy (ERT) in individuals with Pompe disease.

The purpose of Study 010 is to evaluate whether AT2220, an orally available, investigational pharmacological chaperone owned exclusively by Amicus, can be safely co-administered with the ERT alglucosidase alfa, the only approved therapy for Pompe disease. All subjects will be given a regularly scheduled ERT infusion. One hour prior to the initiation of the next ERT infusion, subjects will receive a single oral dose of AT2220. In Study 010, alglucosidase alfa will be measured in plasma and muscle tissue, with and without AT2220.

John F. Crowley, Chairman and Chief Executive Officer of Amicus Therapeutics said, “ERT is an important first generation treatment that has extended the lives of many individuals living with Pompe disease. We believe that chaperone-ERT co-administration has the potential to improve treatment outcomes for Pompe patients, and we are excited about commencing Study 010. Along with our work in Fabry, the co-administration approach may represent an important expansion of our technology platform into other lysosomal storage diseases where ERT is standard of care.”

In acid alpha-glucosidase (GAA) knock-out mouse models of Pompe disease, AT2220 co- administered with ERT increased ERT activity in plasma and uptake into key tissues, which corresponded with greater reductions in muscle glycogen, compared to ERT alone. Collectively these preclinical data highlight the potential for AT2220 to improve ERT in patients with Pompe disease.

“Results from Study 010, if positive, may form the basis for later stage studies that would allow us to evaluate the effect of AT2220 co-administered with ERT on glycogen reduction and ERT- related toxicity in patients with Pompe disease,” said Pol F. Boudes, Chief Medical Officer of Amicus.

Study Design

Study 010 is a Phase 2 open-label, multi-center study to evaluate the safety and pharmacokinetic (PK) effects of four increasing oral doses of AT2220 co-administered with ERT versus ERT alone in individuals with Pompe disease.

The study will enroll approximately 16 male or female subjects who have been on a stable dose and regimen of ERT for at least three months. All subjects will be given a regularly scheduled ERT infusion. One hour prior to the initiation of the next ERT infusion, subjects will receive a single oral dose of AT2220. Plasma enzyme activity and protein levels will be evaluated during each infusion. Muscle biopsies will be taken seven days after each infusion to measure tissue ERT activity with and without the chaperone, as well as the level of AT2220.
More information about Study 010, including patient eligibility, enrollment requirements and study location sites can be obtained by visiting www.clinicaltrials.gov: NCT1380743 or www.pompestudy.com, calling the patient hotline at 855-POMPE-33 (855-766-7333), or e- mailing inquiries to info@pompestudy.com.