Orphan Drug Status for Corneal Cross-Linking in Keratoconus

Yael Waknine

September 14, 2011

September 14, 2011 — The US Food and Drug Administration (FDA) has granted orphan drug status to a 0.1% riboflavin ophthalmic solution (VibeX) combined with an ultraviolet A (UVA) irradiation system (KXL, Avedro, Inc) to perform corneal cross-linking in the treatment of keratoconus.

The action was based on clinical data from 3 US multicenter phase 3 studies.

Corneal collagen cross-linking using UVA light with riboflavin photosensitizer is the first medical therapy available in the United States to control the progression of keratoconus. Most treatments to date have focused on using contact lenses or glasses to mitigate the refractive error induced by progressive thinning and bulging of the cornea. Other options have included corneal implants and corneal transplantation.

The new treatment works by strengthening the cross-links between fibrils that serve as "natural anchors" within the cornea, thereby reducing the abnormal curvature associated with keratoconus.

Widely used in Europe and Asia over the past 12 years, the procedure is being performed in approximately 450 centers worldwide.

"Avedro's effort to make this clinically important treatment available to US patients will be applauded by all US ophthalmologists who today lack any approved therapeutic treatment to halt the progression of keratoconus," said Peter S. Hersh, MD, refractive surgeon and medical monitor for Avedro's clinical trials, in a company news release.

Keratoconus is a degenerative disease of the eye that is characterized by progressive thinning of the cornea and represents the leading cause of corneal transplants in the United States. It affects 1 in every 2000 Americans.

Orphan-drug designation is designed to encourage companies to develop therapies for rare diseases and disorders that affect fewer than 200,000 Americans.

The company is currently seeking FDA orphan drug status in the treatment of corneal ectasia following refractive surgery. The system previously was granted the European CE mark in November 2010.