US approval for Merck & Co’s eye drug Zioptan

Merck & Co's Zioptan (tafluprost) has received US authorisation to reduce increased pressure in the eye.

The US Food and Drug Administration (FDA) has approved the once-daily prostaglandin analogue for use in the reduction of elevated intraocular pressure (IOP) in patients with open-angle glaucoma (OAG) or ocular hypertension.

According to Merck, Zioptan is the first prostaglandin analogue that contains no preservatives to be approved as a treatment for the eye conditions.

Prostaglandin is a chemical that occurs naturally in the body and helps increase the drainage of aqueous humous – a liquid that provides constant pressure within the eyeball through its continuous flow.

When the flow of aqueous humour is blocked, the pressure in the eye can be too great, potentially damaging vision or even leading to blindness.

Zioptan is designed to reduce eye pressure by copying the action of naturally occurring prostaglandin and draining aqueous humour.

It was approved after five clinical studies investigated the treatment in 905 patients.

Both preservative-free and preservative-containing Zioptan demonstrated an ability to significantly lower IOP in patientsover both a three- and six-month period.

“The approval of Zioptan will provide a new, effective option to lower IOP,” said Dr George Spaeth from the Wills Eye Institute in Philadelphia, US.

Merck said it expects to launch the drug in the US in March, 2012.

The US pharma firm obtained rights for the drug in certain markets April 2009 in an agreement with Japan-based Santen Pharmaceutical.

While Santen retained exclusive licence in Germany, Eastern and Northern Europe, and Asia Pacific, Merck has exclusive rights to market the drug in all other Western European markets, as well as North and South America, Africa, the Middle East, India and Australia.

As part of the agreement between the two companies, Santen has the option to co-promote Zioptan in the US. In certain countries outside the US, Zioptan is sold as Saflutan by Merck and Tapros/ Taflotan by Santen.