By Ori Twersky
WASHINGTON (Reuters Health) – A panel of advisors to the US Food and Drug Administration (FDA) on Thursday conditionally backed marketing clearance of a capsular stabilization ring designed to aid patients with weak or no zonules undergoing cataract surgery.
The FDA's Ophthalmic Devices Advisory Committee voted 8 to 1 with one abstention in favor of endorsing the Capsular Tension Ring, which is made by Ring Morcher Gmbh, a family-owned business based in Germany.
The device was designed to help surgeons place an intraocular lens (IOL) after removal of the cataract. During these procedures, the IOL generally is anchored to zonules of the capsular bag.
The marketing application was filed in October and granted an expedited review, a status reserved for novel devices for which there is no marketed alternative.
If approved, the Capsular Tension Ring would be the first such device sold in the US, although similar devices have been available abroad for about a decade.
According to Dr. Roger F. Steinert, associate clinical professor at Harvard Medical School, 2% to 5% of Americans undergoing cataract surgery have weak or no zonules due either to prior injury or hereditary conditions.
Steinert, who served as one of the clinical investigators, told Reuters Health that without the device, such patients would be at risk of complications such as retinal detachment or inflammation.
The panel's conditional endorsement was based on a study of more than 500 patients in which the ring appeared to significantly reduce the complication rate based on the investigators' observations.
But despite the endorsement, the panel expressed significant reservations about the data. Among the shortcomings they cited were tabulation errors and a lack of comparative data to describe the potential side effects and operative failures.
As a result, the panel said its endorsement was conditional on the company supplying additional line-item analyses of the results and possible side effects, as well as materials such as physician and patient educational guides.
Still, the panel said that there was no concrete reason to keep the device out of surgeons' hands. They noted that there did not appear to be side effects, there is a clinical need for such a product, and there seemed to be reasonable evidence that the device would reduce complications despite the lack of comparative data.
"Any help this device provides for stabilizing the capsular bag is better than no help at all," observed Dr. Woodford S. Van Meter, one of the panel's primary reviewers and an associate clinical professor at the University of Kentucky School of Medicine.
Though the FDA is not bound by its panels' advice, it generally follows their recommendations. Nonetheless, the panel's endorsement is no guarantee that the FDA will clear the Capsular Tension Ring for marketing in the near term. According to the agency, there are additional outstanding concerns.
For example, the company will need to pass a manufacturing inspection prior to approval, said Donna R. Lochner, chief of the FDA's Intraocular and Corneal Implants Branch.
She said the FDA and the company were also in discussions regarding issues such as the biocompatibility of the device materials with the eye lens and the microbiology data submitted to support the company's sterilization procedure.