Open-Label Phase 3 Long-Term Safety Study of Migalastat

Study AT1001-041 was an open-label, noncomparative, multicenter, long-term extension study
for participants with Fabry disease who completed treatment in one of three previous trials
of migalastat (AT1001-011 [NCT00925301], AT1001-012 [NCT01218659], or FAB-CL-205
[NCT00526071]). In these trials, migalastat was given as monotherapy. This was an extension
study designed to evaluate the long-term safety and efficacy of migalastat for the treatment
of Fabry disease. Study visits occurred every 6 months (m). Visit evaluations included
physical examinations, clinical laboratory parameters, adverse events, and participant
reported outcomes.

The study consisted of a Baseline Visit, which was performed at the time of the final visit
of the previous study, followed by clinic visits every 6 m for each year of the study. Study
assessments included a physical examination, echocardiography, laboratory parameters, and
participant-reported outcomes. Since participants enrolled in the study at varying time
points based on the completion of the preceding migalastat study, treatment duration varied
among participants. No maximum treatment duration was defined. There were no control groups
in this study; all participants received migalastat as a 150-mg capsule taken orally once
every other day (QOD) and inactive reminder capsules on alternate days.

The sponsor (Amicus Therapeutics) discontinued Study AT1001-041 for logistical reasons and
not due to either safety concerns or lack of efficacy. For participants who were ongoing in
Study AT1001-041 at the time of discontinuation, the investigators were offered participation
in a similar open-label, long-term migalastat treatment study (AT1001-042 [NCT02194985]) for
participants ongoing at discontinuation.

Inclusion Criteria:

- Completed migalastat treatment in a previous Fabry disease protocol

- Both male and female participants were enrolled

- Age 16 years or older

- Male and female participants had to agree to use protocol-identified acceptable
contraception

Exclusion Criteria:

- Estimated glomerular filtration rate (eGFR) in the previous study was <30
milliliters/minute/1.73 square meters (mL/min/1.73 m^2) unless there was a measured
GFR available within 3 m of the Baseline Visit that was >30 mL/min/1.73 m^2

- Had undergone, or was scheduled to undergo, kidney transplantation or was currently on
dialysis

- Pregnant or breast feeding

- Treated with another investigational drug (except migalastat) within 30 days of study
start

- Unable to comply with study requirements, or deemed otherwise unsuitable for study
entry, in the opinion of the investigator

- Had documented transient ischemic attack, stroke, unstable angina, or myocardial
infarction within the 12 m before the Baseline Visit

- Had clinically significant, unstable cardiac disease in the opinion of the
investigator

- Had a history of allergy or sensitivity to migalastat (including excipients) or to
other iminosugars

- Required treatment with Glyset (miglitol) or Zavesca (miglustat)

- Had any intercurrent illness or condition that may have precluded the participant from
fulfilling the protocol requirements

- Had a severe or unsuitable concomitant medical condition

- Had a clinically significant abnormal laboratory value and a clinically significant
electrocardiogram finding at the Baseline Visit.