Lara C. Pullen, PhD

October 27, 2014

CHICAGO — A tapered-release dexamethasone punctum plug appears to be a reasonable alternative to medicated eye drops for patients who have undergone cataract surgery, according to early research.

"In clinical use, the sustained release may reduce patient pain," said Tom Walters, MD, from Texan Eye in Austin. Dr Walters presented the phase 2 study during the cataracts session here at the American Academy of Ophthalmology 2014 Annual Meeting.

The prospective randomized double-masked trial involved 59 patients at 4 sites. The primary end points of the study were the absence of cells in the anterior chamber — a measure of ocular inflammation — and the absence of pain.

Immediately after cataract surgery, patients were randomized; half received the dexamethasone punctum plug and half received a placebo vehicle punctum plug. In this study, the punctum plug was made of polyethylene glycol-based hydrogel and designed to provide a sustained and tapered release of dexamethasone or placebo.

When they were inserted into the punctual, the investigators graded all plugs as easy to visualize.

The patients in the dexamethasone group had fewer cells in their anterior chamber than those in the placebo group, were less likely to require additional anti-inflammatory medications, and had less light sensitivity.

On day 1, mean pain score was three times lower in the dexamethasone group than it was in the placebo group (0.6 vs 2.0).

On day 14, the ocular pain score was 11 times lower in the dexamethasone group than it was in the placebo group.

In addition to providing pain relief, the dexamethasone plug appears to be safe, and no long-term spike in intraocular pressure or adverse events were related to the plug.

Table. Absence of Anterior Chamber Cells in the Two Groups

Time Dexamethasone Plug, % Placebo Plug, % P Value
Day 14 34.5 3.4 .0027
Day 30 62.1 13.8 .0002


After cataract surgery, most patients are prescribed topical eye drops for pain and inflammation; however, many patients do not comply with the recommended dosing regimen.

"Most people who have cataract surgery are older and may have a difficult time adhering to a postoperative eye drop regimen for various reasons," Dr Walters explained. "Getting eye drops onto the eye can be difficult for anybody, especially those who have trouble holding the bottle or targeting the drops into the eye. The punctum plug eliminates those variables, and will make recovery from surgery far easier for cataract patients." The dexamethasone plug will be evaluated next in a phase 3 clinical trial.

"If available, I would definitely use this in my clinical practice," said session panelist Boris Malyugin, MD, chief of the Cataract and Implant Surgery Department and deputy director general of the S.N. Fyodorov Eye Microsurgery Complex State Institution in Moscow.

This is a nice, novel technique," said copanelist George Beiko, MD, assistant clinical professor of ophthalmology at McMaster University in St. Catharines, Ontario, Canada. "It is a very good interim way of delivering what we want to deliver into the eye," he added.

Dr Malyugin raised an issue about the design of the punctum plug, "I am wondering why the group was injecting it into the lower punctual duct." He hypothesized that use of the lower duct, as opposed to the upper duct, might result in more washout of the medicine. The structure of the session did not allow Dr Walters the opportunity to respond.

The study was supported by Ocular Therapix. Dr Malyugin and Dr Beiko have disclosed no relevant financial relationships.

American Academy of Ophthalmology (AAO) 2014 Annual Meeting: Abstract PA004. Presented October 19, 2014.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.