EMEA demands updated Champix warnings

The European Medicines Agency (EMEA) has asked US-based pharmaceutical company Pfizer to include a warning on its smoking cessation product Champix (varenicline), regarding the high risk of suicide attempts among patients taking the drug.

In November 2007, the FDA released an "early communication", which warned of reports of erratic behaviour in patients prescribed Chantix, as it is known in the US. An early communication represents a review and analysis of available data.

Pfizer submitted reports to the FDA describing suicidal thoughts and erratic behaviour in one person who had used the drug, along with at least one other possibly linked death.

The FDA conceded that other factors, including alcohol consumption, appear to have had an impact in this specific case, and the agency asked Pfizer for additional similar cases.

In the EU, Champix, which was first authorised in September 2006 and has been closely monitored by The Committee for Medicinal Products for Human Use (CHMP) regularly as part of routine pharmacovigilance analyses. Cases of suicidal ideation and suicide were reviewed in July, October and November 2007.

At its December 2007 meeting, the CHMP said that Pfizer needed to update the product information to warn doctors and patients that depression has been reported among patients using Champix. The depression may further lead to suicidal thoughts and attempts.

The CHMP has asked Pfizer to submit a variation to the marketing authorisation for Champix before 19 December 2007 to implement these changes to the product information.

Pfizer said there was no scientific evidence that connected Champix to the reported events. It added that it was working closely with the EMEA to review individual case histories.

The labelling update on Champix led to a fall in shares of Pfizer on the 14 December. In Q3 FY07, the drug racked up sales of USD 241m.