By Carolyn Henson, Dow Jones Newswire

An end to the troubles plaguing UCB's key Parkinson's disease formula Neupro looked close Friday after medical experts recommended sales restrictions on the product be lifted in Europe.

Sales could more than double over the next few years once that happens, analysts said.

Neupro patches, which deliver a regular dosage of Neupro through the skin, were taken off the market for all new patients in Europe after they developed crystals that prevented them from working properly.

Cold storage of the product solved the problem, leading to a recommendation Friday from the European Medicines Agency that sales to all Parkinson's Disease patients be resumed.

"Neupro is one of three new drugs at UCB with blockbuster potential," promising annual sales of $1 billion or more, said analyst Thibaud Rutsaert who covers UCB for Bank Degroof.

"The restrictions have held sales flat but this is the first and only patch to treat Parkinson's, offering convenience to patients," he said. "We expect sales to double in the medium to long-term once restrictions are lifted."

Neupro's sales in 2008 were EUR58 million a year, EUR5 million of those in the US where the product was recalled and sales suspended completely.

Full approval in Europe could come by the end of June, UCB said. But sales resumption in the U.S. isn't expected until early in 2010.