Shire wins FDA breakthrough therapy designation for two drugs

Shire has been given an encouraging green light by the US drug regulator for two potential rare disease treatments in its pipeline.

The US Food and Drug Administration (FDA) has bestowed a 'breakthrough therapy designation' on two of Shire's investigational products: SHP621, an oral suspension of budesonide (BOS) to treat dysphagia swallowing difficulty; and SHP625, a potential oral solution of its maralixibat treatment for a childhood liver disorder.

Breakthrough therapy designation is given to therapies that are intended to treat serious or life-threatening diseases or conditions where early clinical trials indicate a substantial improvement over current treatments.

As part of this designation, the FDA provides "intensive guidance" and means, if they continue to show promise, the investigational drugs will be given priority review for their final regulatory application.

In this case, the FDA has granted the designation for BOS to treat eosinophilic esophagitis (EoE), a chronic and rare disease where high numbers of a type of white blood cell in the oesophagus leads to inflammation and difficulty swallowing.

Maralixibat, which has already been granted orphan designation by both the FDA and the European Medicines Agency (EMA) for related indications, has in this case been given the designation to treat progressive familial intrahepatic cholestasis type 2 (PFIC2), the most common type of PFIC autosomal-recessive liver disorder, which disrupts bile formation and causes severe itching of the skin and jaundice.

Shire cautioned that being given breakthrough therapy designation "does not guarantee that FDA will ultimately approve BOS for EoE or maralixibat for PFIC2, and the timing of any such approval is uncertain".

However, chief executive Flemming Ornskov declared the decision on two pipeline products "reflects the potential of our strong and innovative pipeline of more than 60 programs".

Shire noted that EoE is a chronic rare disease that has been increasingly recognized over the past decade, and can lead to strictures causing food getting stuck in the esophagus, poor growth or weight loss and currently has no specific therapeutic options.

Maralixibat, which is being developed as an oral solution formulation for pediatric indications, is currently in Phase 2 trials for PFIC.