FDA ophthalmic panel gives AquaFlow implant the OK

With conditions, the FDA Ophthalmic Panel recommended approval of STAAR Surgical’s collagen glaucoma drainage device.

GAITHERSBURG, Md. — At its 100th meeting here, the Ophthalmic Devices Panel of the Food and Drug Administration (FDA) gave its formal recommendation, with a vote of 10-1 and with conditions, to approve the AquaFlow collagen glaucoma drainage device (STAAR Surgical, Monrovia, Calif.).

Among the conditions placed on the recommendation was a continuation of the follow-up study for another two years. STAAR had provided 2-year follow-up data, but the results included only 18 of the eyes enrolled in the study. The panel asked that the company provide numbers for as many of the original eyes as is reasonably possible. The study enrolled 194 eyes of 130 patients, and 1-year follow-up had included data on 138 eyes.

“I think an effort needs to be made to get 2-year data for more than 8% of the original cohort, especially for a long-term disease like glaucoma,” said Eve Higginbotham, MD, the panel’s glaucoma expert.

Dr. Higginbotham was also troubled by the lack of variety in the age, sex and race of the cohort studied for the drainage device. Most eyes in the study belonged to middle-aged and older Caucasian patients.

In addition to the extended follow-up, the panel asked STAAR to make some modifications to the device’s physician labeling. Among the modifications is a reminder to physicians that the device is approved only for the treatment of open-angle glaucoma and no other forms.

Reduces inflammation and IOP

As part of STAAR’s panel review, Stephen Bylsma, MD, explained the procedure used to insert the AquaFlow. The device is used in non-penetrating deep sclerectomy for glaucoma. Once the outer wall of Schlemm’s canal is removed, the inner wall is partially removed with forceps. By placing the collagen device over the remaining trabecular meshwork, scarring is prevented. It takes about 6 to 9 months for the device to resorb, leaving a long-lasting outflow channel.

STAAR believes the Aqua-Flow may reduce the risk of hypotony, hyphema, choroidal effusion, flat anterior chamber, endophthalmitis and other risks associated with trabeculectomy. According to Dr. Bylsma, immediately following the surgery, patients experienced less intraocular inflammation when compared with standard trabeculectomy patients.

The study results showed that there were no perioperative or postoperative complications directly attributable to the AquaFlow implant. Additionally, patients required fewer postoperative pressure-lowering medications. The average dropped from 2.2 medications per patient to 0.35 per patient.

STAAR’s AquaFlow data showed that the nine-center study of 130 patients, encompassing 194 eyes, reduced mean intraocular pressure (IOP) from 24.2 mm Hg to 16.5 mm Hg at 1-year follow-up.

Questions raised

The only panel member opposed to recommendation of the AquaFlow was Karen Bandeen-Roche, PhD, of Johns Hopkins University. She felt that STAAR’s data fell short of adequately reporting the effectiveness and safety of the implant in the long term. She said her decision was mostly influenced by the study design.

Prior to the vote, several panel members voiced disagreement with how the STAAR study was designed, because it had only a short follow-up of the product. STAAR’s clinical investigator Donald Sanders, MD, explained that because of the nature of the device and its ability to resorb into the body in a period of 6 to 9 months, the device itself could not be studied longer than a 12-month period, followed by a study to gauge the effectiveness of the results. He also explained that STAAR had proceeded with the form of its study based on direction given by the FDA prior to the start of clinical studies.

Panel member Jose Pulido, MD, questioned whether the device was really any better than a typical deep sclerectomy. In the end, however, he voted for the product’s approval.

Dr. Bylsma explained that the advantage of the implant procedure over a deep sclerectomy with no implant is that it avoids over-filtration because of the use of the non-penetrating deep sclerectomy and it avoids late fibrosis because of the collagen implant.

“These patients have good IOP control with quick return to baseline vision without anti-metabolites and, generally, no hypotony. This is good IOP control without frequent postop modulation,” Dr. Bylsma said.

The FDA is not required to follow the panel’s recommendations, but in most cases it does.

For Your Information:

• Eve Higginbotham, MD, can be reached at the Dept. of Ophthalmology, University of Maryland-Baltimore, 419 W. Redwood, Ste. 580, Baltimore, MD 21201; (410) 328-5929; fax: (410) 328-6346; e-mail: ehigginb@umabnet.ab.umd.edu. Dr. Higginbotham has no direct financial interest in any of the products mentioned in this article, nor is she a paid consultant for any companies mentioned.
• Stephen Bylsma, MD, can be reached at Shepard Eye Center, 1414 E. Main St., Santa Monica, CA 93454; (805) 925-2637; fax: (805) 928-2067. Dr. Bylsma has no direct financial interest in any of the products mentioned in this article. However, he is a paid consultant for STAAR.
• Donald Sanders, MD, can be reached at 180 W. Park Ave., Ste. 150, Elmhurst, IL 60126; (630) 530-9700; fax: (630) 530-1636; e-mail: donaldsanders@mediaone.net. Ocular Surgery News could not confirm whether or not Dr. Sanders has a direct financial interest in any of the products mentioned in this article or if he is a paid consultant for any companies mentioned.