Avedro’s 2 riboflavin solutions and cross-linking device are now approved for treatment of progressive keratoconus.
The U.S. FDA this week approved Avedro’s riboflavin ophthalmic solution Photrexa, Photrexa Viscous (a riboflavin solution containing dextran) and an electronic device (KXL System) that irradiates the solutions with ultraviolet A light after they have been applied to the cornea.
Corneal collagen crosslinking (CXL) is the first treatment shown to halt the progression of progressive keratoconus and corneal ectasia by strengthening chemical bonds in the cornea.
In wide use outside the US for about a decade, U.S. physicians have eagerly awaited FDA approval of CXL since the first U.S. clinical trials began in 2008. Some studies have shown that the incidence of corneal transplant procedures has been on the decline since the introduction of CXL.
But Avedro’s product has been slow to gain market clearance. In March 2014, the FDA sent back the company’s new drug application, requesting more information about the KXL device. Significant concerns were raised about the UVA irradiation device that Avedro intended to market because it was not exactly the same one used in the clinical studies submitted to the FDA.
This week’s approval was based on data from 3 prospective, randomized, parallel-group, open-label, placebo-controlled, 12-month trials which showed that treated eyes experienced improved Kmax at 12 months compared with untreated eyes which continued to worsen. Progressive keratoconus patients had an average Kmax reduction of 1.4 D in the first study and 1.7 D in the second study, while untreated eyes had an average increase of 0.5 D and 0.6 D, respectively.
“The approval of CXL in the United States finally brings the only treatment shown to halt progression of keratoconus or corneal ectasia to thousands of Americans,” said Dr. Wuquass Munir, a cornea specialist from the University of Maryland and ONE editor. “The use of CXL in the US could truly change the paradigm of treatment for keratoconus and corneal ectasia, and have a marked impact on the need for keratoplasty in these patients.”
Still, Dr. Munir encourages clinicians “to consider carefully if and when they will incorporate this new technology in their practice, and potentially help patients avoid more invasive procedures.”
ONE Editor Dr. Robert Fintelmann, who participated in Avedro’s clinical trials, said he plans to start using KXL as soon as the company releases their new units.
“Even though there is still controversy as to who will benefit from exactly what treatment (epithellium on versus epithelium off),” Dr. Fintelmann said. “This approval should help shed light on those questions, as well since it will put the treatment in the hands of clinicians.”