What is in Chantix?

CHANTIX™ tablets contain the active ingredient, varenicline (as the tartrate salt), which is a partial agonist selective for α4β2 nicotinic acetylcholine receptor subtypes.
Varenicline, as the tartrate salt, is a powder which is a white to offwhite to slightly yellow solid with the following chemical name: 7,8,9,10tetrahydro6,10methano6Hpyrazino[2,3h][3]benzazepine, (2R,3R)2,3dihydroxybutanedioate (1:1). It is highly soluble in water. Varenicline tartrate has a molecular weight of 361.35 Daltons, and a molecular formula of C13H13N3 • C4H6O6.

Varenicline was discovered at Pfizer through the research aimed at modifying the structure of cytisine, a European smoking cessation aid and also a partial α4β2-nicotinic antagonist. Varenicline received a "priority review" by the U.S. Food and Drug Administration in February 2006, shortening the usual 10-month review period to 6 months because of its demonstrated effectiveness in clinical trials and perceived lack of safety issues. The agency's approval of the drug came on May 11, 2006. Beginning August 1, 2006, varenicline has been available for sale in the United States, and on September 29, 2006, it was approved for sale in the European Union.

CHANTIX contains no nicotine, but it targets the same receptors that nicotine does. CHANTIX is believed to block nicotine from these receptors.Studies show: At the end of 12 weeks of CHANTIX, 44% were able to quit smoking. It also helped reduce the urge to smoke. The trials involved a mix of men and women who smoked on average 10 or more cigarettes a day.

Source: FDA and Chantix