Allergan Inc. has announced that the US Food and Drug Administration (FDA) issued an approvable letter for Combigan (brimonidine tartrate/timolol maleate ophthalmic solution) 0.2 per cent /0.5 per cent for the reduction of elevated intraocular pressure (IOP) in patients with glaucoma or ocular hypertension who require adjunctive or replacement therapy due to inadequately controlled IOP.

An approvable letter outlines the remaining conditions that a company must meet in order to obtain FDA final marketing approval.

"We remain committed to the programme and to working diligently with the FDA on any remaining issues," said Scott M Whitcup, MD, Allergan's executive vice president, research and development. "In its approvable letter, the FDA suggested an additional confirmatory study to address certain questions posed by the Agency. Allergan already commenced a clinical study at the end of 2005 that addresses the remaining FDA questions."

Combigan includes two agents known to reduce IOP - Alphagan (brimonidine tartrate ophthalmic solution 0.2 per cent) and timolol ophthalmic solution 0.5 per cent, a beta-blocker - in one drop. Combigan is approved and marketed in Europe, Canada, Brazil and Australia. Glaucoma currently affects approximately three million people in the United States and 65 million people worldwide and is the leading cause of preventable blindness in the United States.

Elevated IOP, or pressure inside the eye, represents a major risk factor for vision loss associated with glaucoma; the higher the IOP, the greater the likelihood of optic nerve damage, which can lead to vision loss and potential blindness. Reducing elevated IOP is the only treatable glaucoma risk factor.