In the News

As published on Drug Discovery Online, May 11, 2006.

Pfizer's Smoking Cessation Medicine Chantix(TM) (Varenicline) Receives FDA Approval

New York - Pfizer Inc said recently that the U.S. Food and Drug Administration (FDA) has approved Pfizer's anti-smoking pill, Chantix™ (varenicline). Chantix, the first new prescription medication approved for smoking cessation in nearly a decade, received priority review designation by the FDA because of its potential to be a significant therapeutic advance over existing therapies.

Addiction to nicotine is a habit that is very difficult for many smokers to quit. When smokers inhale smoke from a cigarette, nicotine reaches the brain within seconds and binds to nicotinic receptors, which activates the reward pathway in brain circuitry. This stimulates the pleasure center in the brain. The initial effects recede quickly and a cycle of craving and withdrawal takes hold.

Chantix is unique because it is specifically designed to partially activate the nicotinic receptor and reduce the severity of the smoker's craving and the withdrawal symptoms from nicotine. Moreover, if a person smokes a cigarette while receiving treatment, Chantix has the potential to diminish the sense of satisfaction associated with smoking. This may help to prevent the cycle of nicotine addiction.

"I tried to quit smoking so many times but could not until Chantix," said Joe Maloof, a former smoker and Chantix clinical trial participant. "The cravings went down and I finally stopped."

"Pfizer's discovery and development of Chantix demonstrates groundbreaking science leading to the first prescription treatment aimed directly at smoking cessation in nearly a decade," said Hank McKinnell, chairman and chief executive officer of Pfizer. "Smoking harms nearly every organ in the body. It is responsible for approximately one in five deaths in the U.S. and costs the U.S. health care system about $167 billion annually. This medical advance from Pfizer will now help many smokers end their addiction."

Chantix is the fourth new Pfizer medicine to receive FDA approval in 2006.

The other medicines approved are Exubera for diabetes, Eraxis for the treatment of candidemia infections, and Sutent for the treatment of advanced kidney cancer and gastrointestinal stromal tumors.

Chantix's approval was based on a comprehensive clinical trial program including four pivotal trials involving more than 2,000 cigarette smokers. Subjects on average had smoked about 21 cigarettes per day for an average of approximately 25 years. In two identically designed studies, patients receiving a 12-week course of Chantix therapy (1 mg twice daily) nearly quadrupled the likelihood of quitting than those taking placebo and had nearly twice the likelihood of quitting than those patients taking buproprion (150 mg twice daily), after the 12-week course of therapy. Enrolled patients were provided with educational materials. Patients were followed for an additional 40 weeks without treatment. After one year, approximately one-in-five patients who received the 12-week course of Chantix remained smoke-free. For those patients who quit at the end of 12 weeks, an additional course of 12 weeks treatment with Chantix resulted in a greater likelihood of long-term success in quitting smoking.

"These results suggest Chantix is a significant advancement," said Dr. Cheryl Oncken, a Chantix clinical investigator and associate professor of Medicine at the University of Connecticut Health Center. "It is never too late to quit smoking. People who quit smoking before the age of 50 have one- half the risk of dying of a smoking-related illness in the next 15 years compared to those who continue smoking. Patients who are unable to quit on their own should consider seeking medical support and treatment."

In trials, Chantix was generally well tolerated, with overall discontinuation rates similar to placebo. The most common side effects included nausea, changes in dreaming, constipation, gas and vomiting.

Pfizer's Commitment to Smoking Cessation
"As everyone knows, it is extremely difficult to quit smoking," said Karen Katen, Pfizer vice chairman and president of Pfizer Human Health. "For example, less than 7 percent of smokers who try to quit on their own achieve more than one year of abstinence. In fact, most smokers begin smoking again within a few days of attempting to quit. It takes about 10 attempts -- with or without treatment -- before the average smoker is able to quit."

Because smokers need considerable support to successfully quit, Chantix will be available to patients with a support program designed to help address behavioral components of smoking dependence. This personalized program will be free and easy to use.

"Chantix is an excellent example of Pfizer's focus on combating the human and economic cost of disease through prevention and wellness based on scientific innovation and patient support initiatives," said Ms. Katen.

In November 2005, Pfizer submitted a European marketing authorization application for varenicline for smoking cessation.