Cost regulators for NHS therapies in England and Wales have now published final guidelines endorsing the use of Amicus Therapeutics' Galafold for treating the rare genetic disorder Fabry disease.

Fabry disease an inherited lysosomal storage disease caused by a non-functional or only partially functional enzyme called alpha-galactosidase A (alpha-gal A), which results in the build up of enzyme substrates that cause cellular damage in tissues throughout the body and for which there is no cure.

Symptoms include pain that spreads through the body (called a Fabry crisis), gastrointestinal complications, headaches, impaired sweating, vertigo and hearing impairment. The age of onset, severity and progression of the disease is variable, but the disease can have a profound impact on health-related quality of life and can reduce life expectancy.

Galafold (migalastat) is an oral, small molecule drug designed to bind to this enzyme as it is made, helping it to fold correctly and improving its function. It is a life-long treatment, that costs £210,000 per patient per year (excluding VAT and any discounts).

In a final evaluation determination, NICE says the drug can be funded on the NHS within its marketing authorisation, that is for use in people over 16 years of age with an amenable mutation, but only if it is provided with the discount agreed in the patient access scheme and only if enzyme replacement therapy (ERT) would otherwise be offered.

When taking the confidential PAS discount into account, Galafold has a lower total cost than ERT, and potentially provides greater health benefits, the Institute said, but also stressed that there remain "important limitations" and uncertainties in the evidence presented for the drug.

Therefore, it is encouraging the company, NHS England and treatment centres to collect more evidence, particularly on the longer-term benefits of Galafold and ERT for treating Fabry disease, which should inform a future evaluation of the costs and benefits of all treatment options for the condition.

The company estimates that there are 855 people with Fabry disease in England.