Allergy Therapeutics trials on hold, stock tumbles

U.S. regulators have placed clinical trials of an experimental hayfever vaccine on hold after a reported adverse event, dealing a blow to its British maker, Allergy Therapeutics Plc (AGY.L: Quote, Profile , Research).

Shares in company tumbled nearly 19 percent to a six-month low of 96-1/2 pence on the news.

The U.S. Food and Drug Administration placed a hold on clinical studies of Pollinex Quattro -- the company's main product hope -- following a report of a rare adverse event, which the doctor involved in the study said might be related to the treatment.

Allergy said in a statement it was cooperating with the U.S. agency but did not believe Pollinex Quattro was the cause of the problem.

"We believe the evidence strongly supports the view that the event was unlikely to have been caused by Pollinex Quattro and we are seeking urgent clarification of the FDA's position," Chief Executive Keith Carter said in a statement.

Allergy had been hoping to launch its hayfever vaccine, which is designed to help moderate and severe sufferers, in 2009 in the United States. The latest setback to the Phase III clinical trials programme could delay that timetable.

The product has already been given on a named-patient basis to around 100,000 hayfever sufferers in Germany in recent years. Named-patient prescribing is a system that allows doctors to give an unlicensed drug to a specified individual.

The vaccine is given in four injections over a three week period. It costs 450 euros ($619) for four shots in Germany but the price is likely to be higher when it is fully launched, partly reflecting subsequent development of the product.

source:/investing.reuters.co.uk