The European Medicines Agency (EMEA) said it wants the marketer of the adult smoking cessation prescription drug Champix (varenicline) to update the patient and doctor information to mention that some patients on the drugs have been having suicidal thoughts and made attempts to kill themselves.

The European Commission (EC) authorized Champix, marketed by drug company Pfizer, in September 2006. The EMEA Committee for Medicinal Products for Human Use (CHMP) has been monitoring the drug’s safety since then as part of its watching brief. The Committee reviewed reported cases of suicidal ideation and suicide attempts in July, October and November 2007.

At a recent meeting this month, December 2007, the CHMP resolved the product information should be updated to warn doctors and patients about reported cases of depression in patients using Champix to help them stop smoking. Suicidal thoughts (ideation) and attempts are symptoms of depression.

CHMP has asked Pfizer to propose changes to the marketing authorization and product information for Champix, to take into account these post marketing reports, by the day after tomorrow, Wednesday 19th December.

Champix is marketed in the US as Chantix. The active ingredient is varenicline (usually as varenicline tartrate), and is available in tablet form to help adults stop smoking.

In November, the US Food and Drug Administration issued a similar early communication on Chantix, that said it had received a number of post-marketing reports, from the drug company, about patients having suicidal thoughts and behaving erratically while taking the drug.

Both EMEA in Europe and the FDA in the US have stressed the difficulty of finding out if the symptoms are due to varenicline. People can become depressed when they stop smoking, whether they take a drug to help them or not.

Champix is authorized in the following European countries: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Hungary, Ireland, Luxembourg, the Netherlands, Portugal, Slovenia, Slovakia, Spain, Sweden and the United Kingdom. It is also authorized in Iceland and Norway.

In the meantime, until better scientific information is available, the EMEA advises doctors to tell their patients that depression can be a side effect of giving up smoking, and patients on Champix who start to get suicidal thoughts should stop taking the drug and go see their doctor at once.

The EMEA’s CHMP committee has suggested the following changes be made to the information that accompanies the drug:

“Depressed mood may be a symptom of nicotine withdrawal. Depression, including suicidal ideation and suicide attempt, has been reported in patients undergoing a smoking cessation attempt. These symptoms have also been reported while attempting to quit smoking with Champix. Clinicians should be aware of the possible emergence of significant depressive symptomatology in patients undergoing a smoking cessation attempt, and should advise patients accordingly.”

The expected next step is Pfizer will resubmit the marketing authorization in the next day or so, this will be reviewed by the CHMP, and then, all being well, patients and doctors will be given the new warning information.

Click here for detailed scientific assessment of Champix by Europe’s CHMP in 2006 (PDF).

Written by: Catharine Paddock