Pfizer's new drug was inspired by a natural remedy tested by doctors in the Soviet Union in the late 1960s. The Soviet doctors had tested a chemical called cytisine, derived from a weed sometimes called false tobacco, as a pill to help smokers kick the habit. They reported that cytisine partially activated the nicotine receptors in the brain without being addictive.
Pfizer Inc. unveiled an experimental drug to help people quit smoking that could become the drugmaker's next blockbuster.
In clinical trials involving several hundred smokers, the New York-based company said almost half of smokers given this oral medicine, called Varenicline, were able to quit smoking after only seven weeks.
In the same trial, only 16 percent of people receiving sugar pills managed to stop, while 33 percent of patients who received Zyban, a pill sold as Wellbutrin for depression, were able to quit.
"This is a significant improvement over results achieved with Zyban, an antidepressant approved as an aid to smoking cessation." Side effects of the Pfizer drug appeared negligible so far, and the drug has "an excellent safety profile," said Pfizer's spokeswoman.
Varenicline is currently in the final phase of widespread human clinical trials, but there's no timeline for when the anti-smoking drug might hit the market.
The company, however, cautioned that the results of its big clinical studies will take time, and a positive outcome isn't always guaranteed. Pfizer said it is unclear how long patients need to be on Varenicline after quitting.