The US Food and Drug Administration (FDA) has granted Fast Track designation for Shire’s recombinant ADAMTS13 (SHP655 or previously known as BAX930) to treat acute episodes of hereditary thrombotic thrombocytopenic purpura (hTTP).

The life-threatening congenital disease hTTP is caused by a deficiency in the enzyme ADAMTS13, which can cause clotting in the microvasculature with associated organ morbidities.

Shire R&D head Philip Vickers said: "As the leader in rare disease, Shire is committed to providing an innovative pipeline of world-class therapeutics to the patients that need them most.

"Today's confirmation from FDA that SHP655 for hereditary thrombotic thrombocytopenic purpura has been granted Fast Track designation reaffirms the significant unmet need that exists for this patient population and provides hope of reducing morbidity in patients with hTTP."

FDA's designation is supported by preclinical data and a Phase I study.

Data included results from 15 patients with severe hTTP who completed the multicentre study.

The Fast Track process has been designed to facilitate the development, and expedite the review of drugs to treat serious conditions.

Shire plans to initiate its Phase III trial with SHP655 as a randomised, open-label, two-period crossover study in a bid to evaluate its safety and efficacy to treat and prevent acute TTP events in patients with severe hereditary ADAMTS13 deficiency.

The global study will be conducted in the US, Europe, and Japan.

Between 3,000 and 4,000 patients worldwide are currently living with hTTP and there are no approved treatment options.