Yet another about nicotine....
Chantix (varenicline) can be four times as effective in helping a smoker give up cigarettes successfully, according to a report in JAMA (Journal of the American Medical Association), 5 July. According to the report, which cites three studies, Chantix is twice as effective as Zyban (bupropion).
The chances of having a relapse during the first six months after giving up are significantly reduced when a smoker is on Chantix, according to one study.
Chantix was approved by the FDA in May, 2006.
All the studies were funded by the makers of Chantix, Pfizer. A JAMA editorial is sceptical of all the hype surrounding this new smoking cessation drug. Robert Klesges, University of Tennessee Health Science Center, Memphis, USA, says enthusiasm for a new smoking-cessation drug is always high when it first comes onto the market. Even though Chantix has better results than either a placebo or Zyban, this does not necessarily mean it is the holy grail for smoking addicts.
Chantix works in a different way from Zyban or nicotine-replacement therapies. Nicotine-replacement therapies give you a small dose of nicotine - the aim is to provide the smoker with his/her drug while he/she overcomes the enormous psychological problems that come with giving up. Zyban undermines the reuptake of addiction-linked brain chemicals by neurons - dopamanine and norepinephrine. Chantix makes the patient produce more dopamine, which is supposed to help lower the cravings - at the same time brain cell receptors that help perpetuate addiction are blocked.
One study included 1,025 volunteers, all of them smokers who wanted to quit. Chantix, Zyban and a placebo were compared. The study lasted one year. Here are some facts from that study:
-- 44% of those on Chantix were not smoking at 12 weeks
-- 29.5%% of those on Zyban were not smoking at 12 weeks
-- 18% of those on a placebo were not smoking at 12 weeks
-- 22% of those on Chantix did not smoke from week 9 to 52
-- 16% of those on Zyban did not smoke from week 9 to 52
-- 8.4% of those on a placebo did not smoke from week 9 to 52
Another study, from the Unversity of Wisconsin included 1,027 volunteers, all of them smokers who wanted to quit. Results were almost the same as the ones above.
The third study involved people in seven countries - 1,900 smokers who wanted to quit. All of them took Chantix for the first 12 weeks, after which 1,236 (65%) were still not smoking. The 1,236 quitters were then divided into two groups: One group continued taking Chantix while the other took a placebo. This continued for another 12 weeks. At the end of the 24-week period:
-- 70.5% of those on Chantix were not smoking
-- 49.6% of those on a placebo were not smoking
After one year a significantly higher number of those who had been on Chantix were still not smoking compared to those on a placebo.
Chantix has some side effects, which were experienced by about one third of all the volunteers. They included nausea and strange dreams.
Scientists say that the Pfizer funded trials were carried out in ideal conditions for the participant - there was lots of support. Perhaps results may not be as encouraging when a patient gets a prescription from the doctor and is then left to his/own devices.
Even in this third study, which started with 1,900 volunteers, medication and plenty of support, only 871 were not smoking after 24 weeks - less than half.