Johnson & Johnson said that health authorities are reviewing scientific data from two clinical trials evaluating its Alzheimer’s disease drug, Reminyl (galantamine), in mild cognitive impairment after three times more patients taking Reminyl died than those receiving placebo.

The company says that the review was sparked by a preliminary assessment of the data last summer, which showed “an imbalance of mortality.” The studies – known as GAL-INT-11 and GAL-INT-18 – included 2,000 patients and were designed to evaluate a potential decrease in the rate of progression from mild cognitive impairment to dementia. Overall, there were 20 deaths from “various causes” – 15 occurred in the Reminyl treatment group, with the remaining five in the placebo-treated group.

However, J&J notes that overall mortality rates were low in both the Reminyl and placebo groups compared to this particular population or in AD patients. In addition, the firm says that there was no difference in the incidence of overall serious side effects between the two treatment groups.

The firm says that it is currently analysing additional data from the studies, including information retrieved from subjects who had dropped out of the trials, and is discussing the results with regulatory authorities. It confirmed that it has not filed for approval of Reminyl in this indication anywhere in the world, and that no submissions are planned.

J&J’s share price closed down over 1% on the New York Stock Exchange on Friday, and the news also had knock-on effects on this side of the Atlantic, with Shire Pharmaceuticals, which co-developed the drug and has the UK and Irish marketing rights [[02/04/04c]], seeing its share price dip by as much as 4% during morning trading in London today.