MONTREAL – The first real-world effectiveness trial of varenicline for smoking cessation showed that combining the medication with behavioral counseling results in fairly substantial quit rates at 6 months.
Gary Swan, Ph.D., of SRI International, an independent, nonprofit, research and development organization in Menlo Park, Calif., reported on the findings of a trial in which 1,202 smokers, all taking varenicline 2 mg/day, were randomized to one of three behavioral counseling arms: phone only, Internet only, or a combination of both. The counseling programs were available for up to 12 months. The medication was provided by Pfizer Inc., which manufactures varenicline, and the study was funded by the National Cancer Institute. The trial also included researchers from Group Health Center for Health Studies and Free & Clear Inc., both of Seattle.
All of the subjects received a 5–10 minute orientation phone call at the start of the study and were given access to a toll-free phone line. Behavioral counseling based on Free & Clear's Quit for Life Program was then provided via interactive Web tools or through one-on-one phone counseling, or both, Dr. Swan reported at the annual meeting of the Society of Behavioral Medicine.
The average age of the subjects was 47.3 years; two-thirds were female; and they smoked an average of about 20 cigarettes a day.
At the end of the 12-week treatment period, the subjects in the phone counseling group had the highest abstinence rate (48.5%), followed by the phone/Web group (43%), and then the Web-only group (39%). At the 6-month mark, abstinence rates had fallen overall, and there was no longer any statistical difference between groups (34%, 34%, and 31% respectively).
“For those of us who have been working in the field for many years, these are really quite exciting results when compared with other medications, and our results are consistent with those seen in the pre-approval efficacy trials of varenicline,” said Dr. Swan, noting that moderate to severe side effects, including flatulence, altered dreams, altered taste perception, sleep difficulties and changes in appetite, were reported.
He suggested the drop in abstinence after treatment cessation might indicate the need to extend the duration of medication or increase the intensity (frequency of calls) of the behavioral counseling. Phone counseling might improve tolerance to the medication and thus reduce discontinuation because of side effects, he said.
In fact, after 21 days of treatment, a significantly higher percentage of patients in the phone counseling group (87.5%) reported that they were still taking their medication, compared with those in the Web-only group (79%), but not the phone/Web group (83%).
Roughly half of the subjects (48%) reported having made a quit attempt within the preceding year, and the duration of this attempt was a predictor of subsequent success, Dr. Swan noted.
Dr. Swan disclosed that he served as a consultant to Pfizer's National Advisory Board in 2008.