Shares in Elan rose yesterday on news of a scientific breakthrough which could help treat Alzheimer's disease. The share price, which fell on Wednesday to $27 after the Securities and Exchange Commission (SEC) questioned the company's accounting practices, rose again and closed at $29.371/2, up 3.07 per cent.

Elan said it had reversed the development in mice of amyloid plaque, a substance that builds up in the brain of all Alzheimer's patients. The company believes the plaque actually causes the disease and that the treatment may also work on humans.