2nd Quit-Smoking Drug Gets FDA's OK

Pfizer's Chantrix Takes About 12 Weeks; May Work Where Zyban Doesn't

(AP) 

The New York-based company did not immediately release the drug's price. It expects to start selling Chantix in the second half of the year.

Chantix is the fourth Pfizer drug to win FDA approval this year. The others were treatments for diabetes, cancer and bloodstream infections.

Despite the raft of approvals, analysts have been concerned that the new products won't generate enough revenue to compensate for the numerous Pfizer blockbusters that have either lost or will soon lose patent protection.

Varenicline latches on to the same receptors in the brain that nicotine binds to when inhaled in cigarette smoke, an action that leads to the release of dopamine in the pleasure centers of the brain. Taking the drug blocks any inhaled nicotine from reinforcing that effect.

The drug also slows the release of dopamine, which cuts the craving to smoke that occurs when nicotine's effect wears off, said Pfizer research chemist Jotham Coe, who invented the drug. Coe, a former 2½ pack-a-day smoker, quit smoking a first time cold turkey and then a second time with the help of nicotine gum.

One in five American adults, or nearly 45 million people, smoke. An estimated 32 million of those smokers would like to quit, according to the Centers for Disease Control and Prevention. Smoking kills nearly 440,000 Americans a year.

"Tobacco use, particularly cigarette smoking, is the single most preventable cause of death in the United States and is responsible for a growing list of cancers, as well as chronic diseases including those of the lung and heart," said Dr. Scott Gottlieb, the FDA's Deputy Commissioner for Medical and Scientific Affairs.

Quitting isn't easy. Fewer than one in 20 smokers can do so without help, Schroeder said. With help, whether it's a drug, counseling or both, the success rate rises at most to roughly one in five, he added.

Both the FDA and European regulators recently shot down attempts by Sanofi-Aventis SA to gain approval for rimonabant, or Accomplia, as a stop-smoking aid. Both have recommended that the drug be approved for weight loss.

The FDA does not recommend that Chantix be used with other smoking-cessation products. Its most common side effect is nausea.