Antisense Drug Granted Fast Track Designation for Familial Amyloid Polyneuropathy

Isis Pharmaceuticals announced that the FDA has granted ISIS-TTRRx fast track designation for the treatment of familial amyloid polyneuropathy.  ISIS-TTRRx is an antisense drug in development with GlaxoSmithKline for the treatment of transthyretin (TTR) amyloidosis, a severe and rare genetic disease characterized by progressive dysfunction of peripheral nerve and/or heart tissues. 

Transthyretin amyloidosis is a genetic disease in which the patient inherits a mutant gene that produces a misfolded form of TTR, which progressively accumulates in tissues, impairing their function.  In patients with transthyretin amyloidosis, both the mutant and normal forms of TTR can build up as fibrils in tissues, including heart, peripheral nerves, and the gastrointestinal tract.  The presence of TTR aggregates interferes with the normal functions of these tissues, and as the TTR protein aggregates enlarge more tissue damage occurs and the disease worsens. 

A Phase 2/3 clinical study on ISIS-TTRRx, is expected to start this month.

For more information visit www.isispharm.com.