Sanofi-Aventis has announced results from a new study which shows that patients with chronic insomnia who were treated with the firm’s blockbuster hypnotic Ambien managed to perform better at work.

The 728-patient study, which was recently presented at the 20th Annual US Psychiatric and Mental Health Congress in Orlando, Florida, noted that the 478 patients on 12.5mg of Ambien CR (zolpidem) extended-release tablets experienced “significant improvements in two key parameters of work performance – output and time management” – over a period of 12 weeks compared with patients taking placebo. The majority of adverse events experienced by patients in the study were mild to moderate in intensity, and the most frequently reported adverse events participants include headache, anxiety and somnolence.

Milton Erman, clinical professor of psychiatry at the UCSD School of Medicine, was cited by Sanofi as saying that these new data “add to the growing body of evidence that shows that the treatment of chronic

insomnia can improve next day functioning”. The study demonstrates that

Ambien CR-treated patients “did better at work because their sleep improved”, he added.

Ambien is a major earner for Sanofi but the non-extended version of the drug is off-patent in the USA and has started to be battered by generic competition.