The Irish pharmaceutical company Elan is to close its clinical pharmacology unit, with the loss of 16 jobs, the company said yesterday. It is understood the 40-bed facility, based in Athlone, has been under-used in recent months, with company sources blaming the lack of healthy volunteers and "bureaucratic delays" by the medical authorities for the closure.

Last night, Elan would say only the unit was to be wound up, and that of the 22 employees, six were being redeployed. Eight of the remaining 16 workers are parttime, the company said.

However, sources laid some of the blame for the closure on delays by the Irish Medicines Board (IMB), the agency that approves clinical trials. Within Elan there was a view that the board had appeared at times unfounded and unreasonable in its approach, and also took too long to make decisions.

"The IMB's clinical trials committee only meets once a month, and not at all in August or December," one source said. "That can add four or six weeks to the approval process - and the lifeblood of our business is getting approval and bringing a product to market quickly."

The sources stressed that the safety of the trials was not at issue, adding that Elan's tests met with approval from the US Food and Drugs Administration (FDA), known to be one of the world's most stringent pharmaceutical authorities.

A spokesman for the IMB last night said the board would refute any accusations of causing delays.

Other pharmaceutical industry sources said Elan's problems with the speed of approval for tests may lie not with the board but with the legislation, designed to protect consumers, that covers such matters.

It is understood that from January to June this year, the occupancy rate at the clinic was less than 25 per cent. The company has found it increasingly difficult to find healthy volunteers for clinical trials, and this is known to be another reason for yesterday's announcement.

Elan, which in recent years has turned its attention to research into Alzheimer's disease, has its main manufacturing operation in Ireland, with facilities in the United States and Israel. It employs more than 1,500 people worldwide, including around 1,000 between Athlone and Dublin.