GlaxoSmithKline said the US Food and Drug Administration (FDA) has issued an approvable letter for the New Drug Application for Requip (ropinirole) XL extended-release tablets for the treatment of the signs and symptoms of idiopathic Parkinson's disease.

An approvable letter is an official notification from the FDA that contains conditions that must be satisfied prior to obtaining final US marketing approval.

This decision does not affect the immediate-release formulation of Requip (ropinirole hydrochloride) Tablets, which is dosed three times a day and remains an important treatment for patients who suffer from idiopathic Parkinson's disease.

Requip XL is an investigational extended-release, once-daily formulation that uses SkyePharma PLC's patented Geomatrix technology. GSK is committed to working with the FDA to address any questions they have and evaluate the best way forward.

The currently marketed formulation of Requip Tablets is indicated in the US for the treatment of the signs and symptoms of idiopathic Parkinson's disease and is administered three times a day. Prescription Requip is not for everyone. Requip may cause patients to fall asleep or feel sleepy during normal activities such as driving; or to faint or feel dizzy, nauseated, or sweaty when they stand up.

Hallucinations may occur at anytime during treatment. Requip may potentiate the side effects of L-dopa. Side effects include nausea, dizziness, drowsiness or sleepiness, headache, and dyskinesia (uncontrolled movements).

Using its proprietary drug delivery technologies, SkyePharma develops new formulations of known molecules to provide a clinical advantage and life-cycle extension. The company has 11 approved products in the areas of oral, inhalation and topical delivery. The Group's products are marketed throughout the world by leading pharmaceutical companies.

Requip was developed and is marketed by GlaxoSmithKline - one of the world's leading research-based pharmaceutical and healthcare companies.