The European Commission granted a marketing authorisation valid throughout the European Union for Galafold on 26 May 2016. It is a medicine used to treat patients aged 16 years or over with Fabry disease. This is a rare inherited disorder where patients have various mutations in the gene responsible for the production of an enzyme called alpha-galactosidase A, which normally breaks down a fatty substance called globotriaosylceramide (GL-3). In patients with Fabry disease, this enzyme does not work properly. As a result, GL-3 cannot be broken down and it builds up in various cells in the body, including in the heart and kidneys. Galafold contains the active substance migalastat and it is only for use in patients with certain mutations in the alpha-galactosidase A gene. The active substance attaches to certain unstable forms of alpha-galactosidase A, stabilising the enzyme. This allows the enzyme to be transported into areas of the cell where it can break down GL-3. Galafold has been investigated in two main studies involving a total of 127 patients with Fabry disease. The first study, which compared Galafold with placebo (a dummy treatment) in 67 patients, looked at the proportion of patients who responded to treatment (defined as a reduction of at least 50% in GL‑3 deposits in the kidneys). Overall, Galafold was not found to be more effective than placebo at reducing GL‑3 deposits; however, additional analyses including only patients with those genetic mutations that can be treated with Galafold showed that patients responded better to Galafold than to placebo after 6 months of treatment. The second study, in 60 patients, compared Galafold with the medicines agalsidase alfa or agalsidase beta, two treatments that replace the missing enzyme. The main measure of effectiveness was the change in patients’ kidney function after 18 months of treatment. In this study, Galafold was found to be as effective as enzyme replacement in stabilising patients’ kidney function. The most common side effect with Galafold is headache.