14.02 New Glaucoma Drug Zioptan Wins FDA Approval

On Friday, the US Food and Drug Administration approved Merck's Zioptan, a once-daily preservative-free opthalmic solution of tafluprost, a prostaglandin analog for lowering high intra-ocular pressure in patients with open-angle glaucoma or with high intra-ocular pressure.

High intra-ocular pressure or hypertension is when the pressure inside the eye is higher than is considered normal or healthy. Eye pressure, like blood pressure, is measured in millimeters of mercury (mm Hg). Normal eye pressure ranges from 10 to 21 mm Hg. High intra-ocular pressure or hypertension is when this measurement exceeds 21 mm Hg.

People with high intra-ocular pressure are at a higher risk of developing glaucoma, which is when the optic nerve is damaged and vision is lost. Open-angle glaucoma is the most common form.

In 2000, there were about 2.5 million Americans with glaucoma, and more than 130,000 legally blind because of the disease. These numbers underline the importance of identifying, monitoring and treating those at risk for glaucoma, including those with intra-ocular hypertension.

According to Merck, the FDA approval was based on five controlled trials in a total of 905 patients that lasted up to 2 years. The drug was applied once a day in the evenings. Both preservative-containing and preservative-free formulations of tafluprost were used.

The results showed that after 6 months of treatment, mean intra-ocular pressure went down from between 5 to 8 mm Hg. At the start of the trials the mean levels were at between 23 and 26 mm Hg.

The drug may gradually change eyelashes and vellus hair in the treated eye. These changes include increased length, color, thickness, shape and number of lashes, said Merck in a statement. Eyelash changes usually reverse if the treatment stops.

The most common side effect is conjunctival hyperemia, reported in 4 to 20% of participants of the clinical trials.

Serious side effects of tafluprost include macular edema and worsening of any preexisting inflammation.

Merck advises that patients with active intraocular inflammation, aphakic patients, and pseudophakic patients with torn posterior lens capsule, or others at risk for macular edema, should be cautious about using the drug.

They expect Zioptan will be available to customers in March.

For label and other FDA information on the drug, go to Drugs@FDA and enter the drug name Zioptan in the search box.

Written by Catharine Paddock PhD
Copyright: Medical News Today
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