The Lancet Neurology Publishes Pivotal Phase 3 PROPEL Study Results of AT-GAA in Late-Onset Pompe Disease Peer Reviewed Results from PROPEL Show Treatment with AT-GAA Provided Clinically Meaningful Improvements Over Stan

The Lancet Neurology Publishes Pivotal Phase

3 PROPEL Study Results of AT-GAA in Late-Onset Pompe Disease

Peer Reviewed Results from PROPEL Show Treatment

with AT-GAA Provided Clinically Meaningful Improvements Over Standard of Care, including ERT Experienced Patients with High Unmet Need

AT-GAA Deemed to Provide a Differentiated Mechanism

of Action and Potential Alternative Treatment Option for People Living with Late-onset Pompe Disease

PHILADELPHIA, PA, November 18, 2021 -

Amicus Therapeutics (Nasdaq: FOLD), a patient-dedicated global biotechnology company focused on developing and commercializing

novel medicines for rare diseases, announced today that the data from the Phase 3 PROPEL pivotal trial,

assessing the efficacy, safety and tolerability of AT-GAA in adults with late-onset Pompe

disease compared to the standard of care, alglucosidase alfa, were published online in The

Lancet Neurology. The manuscript includes data on the primary

and key secondary endpoints, which were previously reported, as well as additional secondary endpoints. Based on the outcomes observed

in the key domains of Pompe disease (muscle strength, pulmonary and motor function, patient-reported outcomes and biomarkers), the peer

reviewed results determined the PROPEL data showed clinically meaningful improvements over standard of care, even among those who had

been receiving approved therapy for at least 2 years, a subgroup that has been shown to plateau or decline after several years on treatment.

AT-GAA is a two-component therapy consisting of cipaglucosidase alfa, an enhanced phosphorylated

enzyme and miglustat, an enzyme stabilizer, thereby providing a different mechanism of action compared with alglucosidase alfa.

"Pompe disease is a rare

genetic disease that causes premature death and has a debilitating effect on people's lives. There is significant unmet medical

need that persists within Pompe disease and patients are in need of new, effective and safe therapies. The outcomes of the PROPEL study

demonstrate meaningful improvements in motor and respiratory functions in patients who are living with Pompe disease," stated Prof.

Benedikt Schoser, Professor of Neurology at Ludwig-Maximillians-University of Munich LMU Department of Neurology. "Results are particularly

encouraging for the population switching from standard of care ERT to AT-GAA, who saw positive improvements in key manifestations of the

John F. Crowley, Chairman and

Chief Executive Officer of Amicus Therapeutics, stated, "We are pleased that The Lancet Neurology has published our PROPEL pivotal

data in adults living with late-onset Pompe disease. Based on the clinical data we have seen from the Phase 3 trial, in addition to the

body of data that we have accumulated over nearly a decade of preclinical and clinical studies, we have generated a compelling data set

that supports the potential of AT-GAA becoming the next standard of care in the treatment of Pompe disease. We are honored by this publication

and would like to thank all of the investigators, patients and families who participated in the study."

The U.S. Food and Drug

Administration (FDA) previously granted Breakthrough Therapy designation for AT-GAA and accepted for review the Biologics License Application

(BLA) and the New Drug Application (NDA). The FDA has set a Prescription Drug User Fee Act action

date of May 29, 2022 for the NDA and July 29, 2022 for the BLA. In the EU, the Marketing Authorization Applications

for AT-GAA have been submitted in the fourth quarter of 2021.

an investigational two-component therapy that consists of cipaglucosidase alfa (ATB200), a unique recombinant human acid alpha-glucosidase

(rhGAA) enzyme with optimized carbohydrate structures, particularly bis-phosphorylated mannose-6 phosphate (bis-M6P) glycans, to enhance

uptake into cells, administered in conjunction with miglustat (AT2221), a stabilizer of cipaglucosidase alfa. In preclinical studies,

AT-GAA was associated with increased levels of the mature lysosomal form of GAA and reduced glycogen levels in muscle, alleviation of

the autophagic defect and improvements in muscle strength.

addition, Amicus is enrolling an open-label, uncontrolled, multicenter study to evaluate the PK, safety, efficacy, and PD of AT-GAA in

pediatric patients aged 0 to 18 years with LOPD (ATB200-04). More information, including a list of participating sites, is available

at www.clinicaltrials.gov: NCT03911505

an inherited lysosomal disorder caused by deficiency of the enzyme acid alpha-glucosidase (GAA). Reduced or absent levels of GAA levels

lead to accumulation of glycogen in cells, which is believed to result in the clinical manifestations of Pompe disease. The disease can

be debilitating and is characterized by severe muscle weakness that worsens over time. 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. It

is estimated that Pompe disease affects approximately 5,000 to 10,000 people worldwide.

About Amicus Therapeutics

Amicus Therapeutics (Nasdaq: FOLD) is a global,

patient-dedicated biotechnology company focused on discovering, developing and delivering novel high-quality medicines for people living

with rare metabolic diseases. With extraordinary patient focus, Amicus Therapeutics is committed to advancing and expanding a robust

pipeline of cutting-edge, first- or best-in-class medicines for rare metabolic diseases. For more information please visit the company's

Forward Looking Statement

press release contains "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995,

including statements relating to top-line data from a global Phase 3 study to investigate AT-GAA for the treatment of Pompe Disease, the

potential implications on these data for the future advancement and development of AT-GAA, and anticipated regulatory submissions. There

can be no assurance that the FDA will accept a BLA submission or if accepted will grant approval for AT-GAA. Words such as, but not limited

to, "look forward to," "believe," "expect," "anticipate," "estimate," "intend,"

"confidence," "encouraged," "potential," "plan," "targets," "likely,"

"may," "will," "would," "should" and "could," and similar expressions or words

identify forward-looking statements. The forward looking statements included in this press release are based on management's current expectations

and belief's which are subject to a number of risks, uncertainties and factors, including that the Company will not be able to successfully

complete the development of, obtain regulatory approval for, or successfully manufacture and commercialize AT-GAA. In addition, all forward

looking statements are subject to the other risks and uncertainties detailed in our Annual Report on Form 10-K for the year ended December

31, 2020. As a consequence, actual results may differ materially from those set forth in this press release. You are cautioned not to

place undue reliance on these forward-looking statements, which speak only of the date hereof. All forward looking statements are qualified

in their entirety by this cautionary statement and we undertake no obligation to revise this press release to reflect events or circumstances

after the date hereof.

Executive Director, Investor

Head of Global Corporate

Affairs & Communications