Current Research Efforts May Lead to Superior Outcomes

Glaucoma affects an estimated 3 million adults in the United States and remains one of the leading causes of blindness. Treatment options are currently aimed at lowering intraocular pressure (IOP) to prevent ocular nerve damage. Medical or surgical therapy can limit this damage by improving aqueous outflow or reducing aqueous production.

Although existing glaucoma treatment can control elevated IOP and slow disease progression, a cure is still elusive. Glaucoma therapies continue to improve, but further progress is dependent on identifying advances that produce durable results, says Jason C. Swanner, MD, assistant professor of ophthalmology.

Monotherapy with topical medications such as prostaglandin analogues, which increase aqueous fluid outflow, is one of several first-line treatments for glaucoma. However, multidrug regimens — carbonic anhydrase inhibitors plus a beta blocker, for example — often are necessary to achieve therapeutic goals, Swanner says.

Current glaucoma research includes clinical trials examining memantine, a drug used to treat Parkinson’s disease and Alzheimer’s disease. Researchers in UAB’s Department of Ophthalmology are studying the drug’s effect on the optic nerve. Results of these phase 3 trials will not be available for some time, but investigators are optimistic that memantine may offer some protection to the optic nerve.

Surgical intervention for glaucoma may be appropriate when patients do not achieve target IOP with successive medical therapies. Advances in surgery include selective laser trabeculoplasty (SLT), which improves fluid drainage while avoiding the ocular scarring associated with traditional argon laser trabeculoplasty (ALT).

A clinical trial underway at UAB compares the effectiveness of the SOLX Gold shunt, an investigational aqueous implant, with the Ahmed Glaucoma Valve. Both devices increase aqueous outflow to lower IOP. Although currently approved shunts may not reduce IOP as effectively as SLT or ALT, they lower the risk of scarring. Candidates for the SOLX trial are individuals with primary open-angle glaucoma who have not responded adequately to medication and conventional first-line surgical interventions.

The SOLX Gold shunt is in phase 3 trials throughout the United States, Canada, and Israel. UAB is 1 of 11 participating centers. “The SOLX implant is different because it creates a new fluid pathway by connecting the anterior ocular chamber and the suprachoroidal space,” Swanner says. “The SOLX shunt remains permanently in the suprachoroidal space and may prevent the scarring associated with other surgical methods.”

In addition to its innovative placement, the shunt is made of 24-karat gold and contains multiple channels that can be opened to provide additional flow routes from the anterior chamber to the suprachoroidal space. This new method of IOP control allows postsurgical adjustment to achieve target pressures.

“If the SOLX shunt effectively lowers IOP, its novel aspects represent promising advances that could optimize outcomes for patients in the near future,” Swanner says.

For more information:
Dr. Jason Swanner
1.800.UAB.MIST
mist@uabmc.edu