Probe into anti-smoking drug linked to suicide
An investigation has begun into the safety of an anti-smoking drug after it was linked to a suicide in America.
Patients taking Chantix in the United States, known as Champix in Britain, are being advised by the authorities to contact their doctor if they experience mood changes or feel depressed
Pfizer, the manufacturer, has also been asked by the US Food and Drug Administration to submit any data on cases where users have described suicidal thoughts. It follows a report of the suicide of a patient taking the drug.
The labelling will also be updated to include suicide and suicidal thoughts in the list of adverse events that have happened while patients have taken the drug.
Champix can double the chance of quitting smoking after a year from 10 per cent to 20 per cent. About 500,000 people have used the drug in Europe while four million have taken its equivalent in the US.
In Britain, between 15,000 and 20,000 people have used Champix since it was launched in December last year.
The Medicines and Health Regulatory Agency, which licences and monitors drugs in this country, has had 46 reports of depression associated with the the use of Champix and 16 reports of patients experiencing suicidal thoughts. There have been no reported suicides.
There has been no evidence that the drug causes depression or suicidal feelings and it is well known that stopping smoking can exacerbate existing psychiatric conditions.
The prescribing information leaflet already contains warnings that it should be used with care in people with a previous psychiatric illness such as depression. Last month, the MHRA repeated warnings that patients taking Champix should not drive until they know how the drug affects them as it can cause drowsiness in some people, with two patients on it being involved in car accidents.
A spokesman for the MHRA said there had been no reported suicides but it was monitoring closely the issue of suicidal tendencies in patients taking Champix.
Champix, which contains the active ingredient varenicline, relieves craving and withdrawal symptoms as well as removing the satisfaction gained from cigarettes.
The drug is taken twice a day for 12 weeks.
A spokesman for Pfizer said: There is no scientific evidence establishing a causal relationship between varenicline and the post marketing report events. The adverse reaction section of the US label is being updated to include spontaneous post-marketing adverse event reports of depressed mood, agitation, changes in behaviour, suicidal ideation, and suicide in patients attempting to quit smoking while taking vaernicline.
Pfizer is in close contact with the European Agency (EMEA) regarding the FDA communication. Pfizer is assessing the potential impact on the European product information and will continue to collaborate with the EMEA on any further developments. All available safety data has been made available to the regulators previously.
At Pfizer, patient safety is our first priority. We are comitted to the safety of all our medicines. Pfizer is vigilant in monitoring adverse drug reports for all of its products, and has extensive systems in place to collect, review and report these data.back