Prevalence of migalastat-amenable variants in patients with Fabry disease from Brazil, Argentina, and Colombia: an observational study

Introduction Fabry disease is a progressive, X-linked lysosomal disorder caused by GLA variants that result in dysfunctional α-galactosidase A (α-Gal A) enzyme. One treatment option is migalastat, an oral small-molecule pharmacological chaperone treatment for patients with migalastat-amenable GLA variants. Methods In this retrospective study, medical records were used to determine the prevalence of migalastat-amenable variants among individuals managed for Fabry disease at centers in Brazil, Argentina, and Colombia (primary endpoint). Demographic and clinical characteristics were explored using available data. Medical records of males or females of any age with a diagnosis of Fabry disease (based on genetic testing and/or α-Gal A enzymatic activity) were eligible for inclusion. Results Data were collected for 1,196 individuals diagnosed with Fabry disease in Brazil (n = 1,000), Argentina (n = 122), and Colombia (n = 74); of these, 720 (60.2%) had migalastat-amenable GLA variants (650 [65.0%] patients in Brazil, 32 [26.2%] in Argentina, and 38 [51.4%] in Colombia). The migalastat-amenable variants differed by country with little overlap among the cohorts in Brazil, Argentina, and Colombia in the most common variants. Median age (in years) at the study reference date (July 1, 2021) for individuals with migalastat-amenable variants was 45.6, 44.1, and 21.8 years in Brazil, Argentina, and Colombia, respectively. Data on clinical characteristics were available only in Argentina and Colombia. Discussion In those for whom data were available, there appeared to be both objective and subjective manifestations of Fabry disease, as evidenced by renal impairment, cardiac involvement, and classic Fabry disease signs and symptoms.