Updated

People trying to quit smoking may be more likely to succeed if they combine the patch with a pill, suggests a new study from South Africa.

According to the study's authors, the findings challenge previous research that found no added benefit from combining the smoking cessation drug varenicline, marketed in the U.S. as Chantix by Pfizer, with nicotine patches.

“The studies that have been done in the past didn’t show any difference, but they were inadequate to the task both in terms of how long they followed the patients as well as the number of patients involved,” said Dr. Hal Strelnick, a smoking cessation specialist who was not involved in the new study.

The new results may encourage some doctors to treat patients who failed with other methods to quit smoking with the combination pill and patch, said Strelnick, division chief of community health and professor of clinical family and social medicine at Albert Einstein College of Medicine and Montefiore Medical Center in the Bronx, New York.

For the new study, Dr. Coenraad Koegelenberg from Stellenbosch University in Cape Town and his colleagues recruited 446 people from seven healthcare centers around South Africa from April 2011 to October 2012.

The researchers randomly assigned the participants to receive real or fake nicotine patches, which they would start wearing two weeks before a chosen quit date. One week before that date, all participants were put on varenicline, which they continued to take for about three months.

By measuring the amount of carbon monoxide in participants' breath to confirm abstinence from tobacco, the researchers found that about 55 percent of those using the pill and real nicotine patch were smoke-free after 12 weeks, compared to about 41 percent of people using the pill and fake patch.

After 24 weeks, 49 percent of people in the pill and real-patch group were smoke-free, compared to 33 percent using the pill and the fake patch. Those using the pill and real patch were also more likely to be smoke-free at six months, according to the results published in JAMA.

The occurrence of side effects was equal between the two groups, but skin reactions were about twice as common among the people using the real nicotine patch.

In an email, Koegelenberg told Reuters Health that more studies are needed to prove that the combination therapy is safe.

Varenicline attaches to the same brain receptors that are activated by nicotine, but the drug blocks nicotine from getting to those receptors while also partially activating them, the authors point out in their report.

Koegelenberg said that while he and his colleagues can’t be sure why the combination worked so well in their study, they believe the combined treatments saturate more nicotine receptors in the brain and lessen cravings, compared to using the pill or patch alone.

Strelnick said doctors can legally prescribe varenicline and nicotine patches, but it hasn’t been recommended in the past.

“This study would begin to change the way we approached those more difficult patients, because the past evidence showed there was no benefit and you risked spending the money and experiencing the side effects of two medications instead of one,” he said.

Those more difficult patients include people who tried other treatments, such as varenicline alone or a combination of short acting nicotine replacement products like nasal sprays or lozenges with long acting nicotine replacement like patches, and couldn't kick their smoking habit.

Varenicline comes with a so-called black box warning and its manufacturer says that some people taking the medication have experienced changes in behavior, hostility, agitation, mood and suicidal thoughts and actions.

Strelnick said he hoped the findings of the new study encourage others to research the long-term effects of the combination therapy in an effort to get an endorsement for it from the U.S. Food and Drug Administration (FDA).

“I think there is a place for having that supported by the FDA in the materials that recommend treatment,” he said.

“Quitting smoking is the single most important thing any smoker can do for their health if they want to improve their quality of life.”