Just a Drop May Slow Vision Loss

Latanoprost to treat glaucoma slowed vision loss and decreased intraocular pressure

(RxWiki News) Glaucoma patients face the threat of vision loss. Fortunately, a common eye drop prescription for glaucoma may reduce that threat.

In a new study, eye drops that contained latanoprost (brand name Xalatan) decreased pressure in glaucoma patients' eyes and maintained their vision longer — compared to patients who didn't use the medication.

The authors of this study said latanoprost is often used to treat glaucoma, and this was the first study that showed that it worked to slow vision loss.

"Our findings offer solid proof to patients and practitioners that the visual deterioration caused by glaucoma can be reduced by this treatment," said lead study author David F. Garway-Heath, MD, of the National Institute for Health Research Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust in London, in a press release.

Tom Jennings, MD, a board-certified ophthalmologist practicing in Dallas, TX, said patients can take steps to catch glaucoma early.

"The best way for an early diagnosis of glaucoma is a routine, dilated eye exam where dilating drops are placed in the patient's eyes to enlarge the patient's pupil," he told dailyRx News. "A dilated pupil facilitates the examination of the optic nerve and retina."

Dr. Garway-Heath and colleagues enrolled 516 patients with glaucoma in the current study. Glaucoma patients have damage to the optic (eye) nerve that can cause loss of vision and eventual blindness. Most patients with glaucoma also have an increase in the pressure within the eye.

In this study, eye pressure was measured in units called millimeters of mercury (mm Hg). The average pressure within the eyes of patients at the start of the study was 20 mm Hg.

One group of patients in the study used eye drops containing latanoprost. The other group used eye drops that did not contain the medication. The study team measured the vision changes and pressure in the eyes of the patients over a two-year period.

The patients who used latanoprost showed a decrease in pressure in the eye of nearly 4 mm Hg — compared to about 1 mm Hg in the group who didn't use latanoprost.

The field of vision — the entire area that patients could see — remained stable longer in the group whose eye drops contained the medication than in those whose did not. That means the vision in those patients did not deteriorate as quickly.

The risk of vision loss was more than 50 percent reduced in patients who used latanoprost than in those who did not.

Strengths of the study by Dr. Garway-Heath and colleagues include the amount of improvement patients received from the medication and the short amount of time before improvement was seen, said Anders Heijl, of Skane University Hospital in Malmo, Sweden, in an editorial on this study.

"These results should motivate careful clinical follow-up and monitoring of disease progression in patients with glaucoma, and should also serve as a stimulus to the pharmaceutical industry to continue development of new and even more potent drugs," Dr. Heijl wrote.

The study and editorial were published online Dec. 19 in The Lancet.

Pfizer and the NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology funded this research.

Several authors received research funding or lecture honoraria from Allergan, a manufacturer of latanoprost, and Pfizer, a sponsor of the study. Dr. Heijl received consulting fees and honoraria from Allergan.

Review Date: 
December 18, 2014