Chantix (varenicline) was shown to be effective with a favourable safety profile as an aid to smoking cessation treatment, according to three pivotal studies published in this week's Journal of the American Medical Association.

Chantix, the first new prescription smoking cessation medication approved in nearly a decade, received US Food and Drug Administration approval on May 10. Chantix is expected to be available in US pharmacies in August. Because smokers need considerable support to successfully quit, Chantix will be available to patients with a support program designed to help address behavioural components of smoking dependence. This personalized programme will be offered at no additional cost and easy to use.

"According to the World Health Organization, every eight seconds a person dies of a smoking-related disease -- almost as quickly as someone else takes up smoking for the first time," said Dr. Joseph Feczko, Pfizer's chief medical officer. "Chantix represents a significant new discovery for smokers who are trying to quit."

Data show that approximately 44 per cent of patients treated with Chantix (1mg twice a day) quit smoking by the end of the 12-week treatment period versus 30 per cent who used buproprion SR (150mg twice a day) and 18 percent who used placebo. In an additional phase III clinical trial, patients who remained quit after 12 weeks of treatment with Chantix were randomized to receive an additional 12 weeks of treatment with Chantix or placebo. At the end of 24 weeks, 70.5 per cent of patients on Chantix continued to abstain from smoking compared to 50 per cent who switched to placebo.

In trials, Chantix was generally well tolerated with overall discontinuation rates similar to placebo. The most frequent side effects included nausea, headache, trouble sleeping and changes in dreaming.

In November 2005, Pfizer submitted a European marketing authorization application for varenicline for smoking cessation.