Research suggests that about 70% of current smokers want to stop smoking, and that the average smoker tries to quit six to nine times in a lifetime. Why is it so tough to kick this habit?
A few minutes after you smoke a cigarette, nicotine levels rise and then fall in your bloodstream. A smoker's brain cells have receptors that are stimulated by nicotine. This generates a subsequent release of dopamine that results in the pleasurable sensation that smokers crave. A smoker who has repeated exposure to nicotine over long periods of time will actually have more of these receptors present in the brain, due to a process called upregulation.
Nicotine patches and nicotine gum, like GlaxoSmithKline's (NYSE:GSK) Nicorette, are old treatment options for smoking cessation. But the low concentration of nicotine provided by the patch cannot compete with the higher nicotine dose that intermittent puffing provides. So these treatments work, but not all that well.
Glaxo's Zyban, an antidepressant drug found to be helpful in getting some smokers to quit, was approved by the FDA for use as a smoking cessation medication in 1997. A 1999 study in the New England Journal of Medicine found that that abstinence rates were 15.6% in a placebo group, 16.4% in the nicotine-patch group, 30.3% in Zyban group, and 35.5% in the Zyban plus nicotine-patch group. So there is evidence of improved therapy, but newer treatment options would be welcomed. (Moreover, Zyban was not designed to help smokers stop smoking, and many smokers understandably do not want to be on an antidepressant. Additionally, some people are already on an antidepressant, so that complicates its use somewhat.)
On May 11, 2006, the FDA approved Pfizer's (NYSE:PFE) new smoking cessation drug, Chantix. Chantix binds to the same receptors that are stimulated by nicotine, and thus prevents nicotine from binding to those receptor. Hence, when two friends of mine, both lifelong smokers, lit up after a week, their receptors were already full and they didn't receive any pleasurable sensation -- they were merely blowing smoke. Since those pesky receptors were full, the craving symptoms were dramatically lessened as well.
In the July 5, 2006 edition of the Journal of the American Medical Association, Douglas Jorenby and others published the results of a trial comparing Chantix to Zyban. They found that at one year, 23% taking Chantix had stopped compared with 10.3% in the placebo group and 14.6% in the Zyban group.
Chantix is far from a miracle drug, but it is still a significant improvement. Apparently, most folks won't have the success that my friends did, but for those who do have long-term success -- for potentially those millions that want to stop smoking but can't -- the drug can nearly be called a miracle drug. The CDC lists smoking as the single most preventable cause of premature death in the U.S., where one in every five deaths are smoking-related.
In my opinion, Pfizer has been slow to market this drug, but this is about to change. Last week Pfizer announced that it had hired McCann HumanCare of the Interpublic Group (NYSE:IPG) to market Chantix; the estimated media spending would be $75 million. Previously Pfizer had hoped that sales would eventually reach $1 billion annually; it is possible that Chantix could become Pfizer's next blockbuster drug.
Pfizer's shareholders could use some good news, since the stock has performed so poorly over the last five years and the company's future is murky, with flagship product Lipitor going off patent in a few short years. Now may be a good time for value investors to consider purchasing Pfizer shares.
Pfizer is an Inside Value recommendation. GlaxoSmithKline is an Income Investor selection.
Fool contributor Dr. Michael Cecil is a cardiologist and the author of Drugs for Less: The Complete Guide to Free and Discounted Prescription Drugs. He welcomes comments and discussion about this article. Dr. Cecil does not own any of the stocks mentioned in the article.The Fool has a disclosure policy.
