Monday, November 14, 2011
Researchers Eye a Cheap, Organic Alternative to Chantix for Smokers
Meet cytisine, available in Bulgaria for 25 cents a pill.
A clear majority of American smokers say they want to quit. But each year, only a small percentage of them manage to do it. For individual smokers, the will is there, but what’s sometimes missing is the money.
For many smokers, cessation aids like nicotine patches and anti-craving medication are effective. But they are relatively costly, and insurance coverage for such products varies widely. Chantix, the top-of-the-line smoking cessation aid introduced by Pfizer five years ago as a very expensive prescription drug, was discovered by modifying the chemical attributes of an existing plant substance called cytisine.
But what if cytisine itself, found in various plants, including the golden rain tree, a small shrub native to the Alps—worked almost as well as Chantix, but for only pennies a day? Cytisine, packaged as Tabex and marketed by a Bulgarian firm, has already been on the market in Central Europe and Russia for more than 40 years. In Russia, a four-week course of Tabex costs $6. Chantix will cost smokers about $250 for a 12-week run, or about $3-$4 per pill. In Poland, Tabex sells for about 25 cents per pill.
Moreover, as David Biello pointed out in Scientific American, when Chantix (known as Champix in the U.K.) was first approved for use against cigarettes, “the leaves of Cytisus laburnum, or the golden rain acacia tree, were used as a tobacco substitute by soldiers in World War II.” Later, clinicians in the U.S. paid scant attention to reports of a cheap Bulgarian plant-based supplement that smokers in Russia and Central Europe were using to help break their nicotine addiction. Instead, researchers structurally modified cytisine to produce varenicline, or Chantix. It makes for a more effective drug, but there are always tradeoffs: It is expensive and time-consuming to produce drugs through a process of total syntheses, and they will always come at a considerable cost premium relative to their organic originals. That is partly how pharmacology works, and it’s a good thing, providing you have the money or the health insurance to be able to afford the finished product.
Recently, a group of researchers at a smoking cessation clinic in Poland studied the effect of cytisine, a “partial nicotine agonist,” in a clinical trial published
in the New England Journal of Medicine. The double-blind trial showed that cytisine was not as effective as Chantix, but significantly more effective than a placebo. Dr. Robert West of University College, London, and lead author of the study, said the “net improvement in the abstinence rate with cytisine was 6 percentage points. The relative rate of abstinence in the cytisine group as compared with that in the placebo group was 3.4.”
“It wasn't compared head-to-head against the Rx drugs, but its reasonable efficacy makes it sound like a cheaper alternative,” said Dr. David Kroll, Professor and Chair of Pharmaceutical Science at North Carolina Central University. “Like nicotine, it can cause side effects like headaches and nausea,” he added.
So is cytisine an eventual possibility in the U.S., where it is not currently licensed and available? Is it something that the National Institute on Drug Abuse is interested in? When I asked NIDA director Nora Volkow that question in an interview last week, the answer was yes. “The data look very interesting,” Volkow said, referring to the New England Journal of Medicine Study. “The beauty of cytisine is that it’s not just inexpensive, you can also get a response in three weeks.” She added that “we don’t know yet whether we can improve it,” by, for example, combining it with other cessation aids. “The main side effect of cytisine is nausea, but not suicidal ideation,” she said.
An earlier survey in the Archives of Internal Medicine of the admittedly sparse research showed similar results in several placebo-controlled double-blind studies. Cytisine, the Marxist-Socialist answer to cigarette addiction, works about as well as standard nicotine replacement therapy, like patches and gums.
“I hope this drug will be available throughout the world at a cost that every smoker can afford,” said West. And that might be a problem. Cytisine is not currently legal in the U.S. or Canada. Tabex itself was withdrawn from some of the European countries in which it was formerly available, after several Central and Eastern European countries joined the European Union and began adhering to stricter licensing rules.
Meanwhile, a third of the world is still out there smoking tobacco. It seems sensible to have some modest help available for smokers in poverty who want to quit and financially need to quit. “I have long been concerned that effective treatments to help smokers to stop are not affordable by the majority of smokers in the world,” West said. “There are still regulatory hoops to go through, but I hope that before long this drug will be available throughout the world at a cost that every smoker can afford. It should be cheaper to take this drug than to smoke, wherever you are in the world. It is not a magic cure by any means; stopping is still extremely difficult for many people. But it could save many hundreds of thousands of lives, if not millions, which is quite a thought.”
As Dr. Volkow put it: “We urgently need medications for smoking. Five million people die per year” from smoking-related causes in the U.S.
West R, Zatonski W, Cedzynska M, Lewandowska D, Pazik J, Aveyard P, & Stapleton J (2011). Placebo-controlled trial of cytisine for smoking cessation. The New England journal of medicine, 365 (13), 1193-200 PMID: 21991893