The chairman of Galen, Dr Allen McClay, said that the acquisition of New Jersey firm, Interactive Clinical technologies, would complement and strengthen Galen's clinical trial service in the US and Europe.

ICT, which employs just 30 people, provides a range of services for clinical trials in the pharmaceutical industry, an area into which Galen is seeking to increase its involvement.

"It will help us to use interactive voice response, and other innovative systems to improve the efficiency of the clinical trials process," Dr McClay said.

Galen, which was floated on the London Stock Exchange in 1997, was founded in 1968 by Dr McClay, and employs around 800 people at its facilities in Craigavon and Larne, and another 200 in Pennsylvania, where there is a £7 million centre specialising in manufacturing and clinical trials.

Last year it announced that it would be recruiting another 125 people following a £21.5 million investment programme.