The FDA has granted Fast Track designation for Shire’s SHP609 (idursulfase-IT; also known as HGT-2310) for the treatment of neurocognitive decline associated with Hunter syndrome (mucopolysaccharidosis II or MPSII).

This investigational formulation of idursulfase has been designed for direct administration into the cerebrospinal fluid via an intrathecal drug delivery device (IDDD). This formulation is being investigated and developed for use with Shire's currently approved treatment for Hunter syndrome, ELAPRASE (idursulfase). ELAPRASE is administered intravenously and does not cross the blood-brain barrier in clinically relevant amounts.

"This is not only the first treatment being investigated to address the significant unmet need of slowing the cognitive decline in MPS II patients, but also the furthest an intrathecal program for enzyme replacement has ever progressed," said Dr. Philip J. Vickers, head of R&D at Shire. "This Fast Track designation is further recognition of the critical need to develop new, effective therapy options for patients with Hunter syndrome with cognitive impairment."

The FDA's Fast Track program is designed to facilitate the development and expedite the review of drugs that address serious or life-threatening conditions and that demonstrate the potential to address unmet medical needs. Fast Track designation provides increased opportunities to interact and meet with FDA, and increases the likelihood of being eligible for priority review if supported by clinical data at the time of BLA.

Shire currently is enrolling patients in its phase II/III pivotal trial (HGT-HIT-094 or AIM-IT), which is a controlled, randomized, open-label, multi-center, assessor-blinded study designed to determine the effect on clinical parameters of neurodevelopmental status of monthly administration of idursulfase IT in pediatric patients with Hunter syndrome and early cognitive impairment who already receive and tolerate therapy with ELAPRASE. An extension study also is planned to assess long-term safety and efficacy.

Hunter syndrome is a severely debilitating rare disease that affects one in 162,000 total live births, and mainly males. Hunter syndrome is an X-linked disorder caused by a deficiency or absence of the lysosomal enzyme iduronate-2-sulfatase (I2S), which leads to severe clinical complications and early mortality.