Jury Out on Added Value of Varenicline in Adolescent Smokers

By Megan Brooks

October 16, 2019

NEW YORK (Reuters Health) - In a study of adolescent daily smokers, treatment with the smoking cessation drug varenicline was well tolerated but did not boost abstinence rates at the end of treatment, the trial's primary outcome.

However, adolescents taking varenicline achieved abstinence earlier and had higher rates of overall abstinence during treatment and at follow-up after treatment ended, two secondary outcomes of the trial.

"The present findings add to a mixed literature on adolescent smoking cessation interventions, which have generally yielded discouragingly low rates of abstinence in psychosocial and pharmacological treatment trials," the investigators say in a paper online today in JAMA Pediatrics.

"Although present findings indicate that abstinence did not differ between the varenicline and placebo groups at the end of treatment, the secondary findings of earlier and sustained posttreatment follow-up response to varenicline suggest that it may provide an advantage in yielding longer-term abstinence among adolescent smokers," write Dr. Kevin Gray and colleagues from the Medical University of South Carolina in Charleston.

In contrast to the wealth of studies evaluating varenicline in adult smokers, few have tested the drug's safety and efficacy in adolescent smokers, they point out.

The current study included 157 daily smokers between 14 and 21 years old who wanted help quitting. In addition to weekly smoking cessation counseling, 77 participants received a 12-week course of varenicline and 80 received placebo.

There was no difference between varenicline and placebo groups in the primary outcome of cotinine-confirmed self-reported 7-day abstinence at the end of the 12-week treatment period (8.9% abstinence in both groups).

However, those taking varenicline had nearly twice the probability of any self-reported abstinence during treatment. They were also more likely to achieve 7 consecutive days of abstinence (40.3% vs 30.0%). Varenicline treatment also shortened the time to 7 consecutive days of abstinence by 20 days.

Treatment-emergent adverse events, in general and specific to neuropsychiatric events, did not differ between the varenicline and placebo groups. However, adolescents with a history of mood or psychotic disorders, suicidality, or hostility/aggression) were excluded from the trial. "How the safety or efficacy findings may translate to adolescents with co-occurring psychiatric disorders, who are disproportionately represented among adolescent smokers, is not clear," the investigators note.

In email to Reuters Health, Dr. Gray noted that "participant recruitment is always a challenge in this line of work. While many adolescents smoke cigarettes, fewer are daily smokers that recognize that they may need help quitting. The study’s participants made important contributions to science, and many were successful in reducing or quitting smoking."

Dr. Gray also noted that prior work by his team shows that "behavioral incentives (e.g., vouchers for smoking abstinence at treatment visits) significantly bolster response to medication treatment for adolescent smoking cessation. Given that there appears to be an effect of varenicline in the present study (albeit not at the end-of-treatment visit), it would be valuable to see if combining varenicline with behavioral incentives would yield a more robust smoking cessation response."

In a linked editorial, Dr. Megan Piper of the University of Wisconsin Center for Tobacco Research and Intervention and co-authors say there is a "huge, unmet public health need" for smoking cessation treatments for younger smokers. Varenicline treatment for young smokers "deserves further investigation" (but) its general use with this population cannot, at present, be endorsed."

The editorial writers say one reason for the low success rates in this study might be that the demands and format of the treatment program did not fit the young population. "For instance, the 12 in-person sessions were sparsely attended. Alternative formats including text-, telephone-, or web-based support and counseling might be more effective in engaging and sustaining the interest needed for successful quit attempts in this population," they say.

Dr. Gray agrees, telling Reuters Health that in future studies, his team will "leverage mobile technology to help keep participants engaged, including reminders for medication dosing and participant visits, and potentially including treatment and data collection opportunities that can be conducted remotely, while still assuring privacy and confidentiality for participants. We are incorporating these strategies in our ongoing work, and our adolescent participants have been very receptive and engaged."

The study was supported by grants from the National Institutes of Health. Varenicline and placebo tablets were supplied at no cost by Pfizer. Dr. Gray reported consulting for Pfizer, Inc, and receiving grant support from the NIH.

SOURCE: http://bit.ly/32ic5FU and http://bit.ly/33zevAb

JAMA Pediatrics 2019.