ESTEs PARK, COLO. -- Three major drug classes with diverse mechanisms of action are now approved for smoking cessation, providing an unprecedented array of options in terms of sequential and combination therapies.
Trying different agents, recycling them, combining them, and providing more intensive behavioral support are all important strategies, Dr. Allan Prochazka said at a conference on internal medicine sponsored by the University of Colorado.
Combination drug therapy is usually more effective than monotherapy, particularly for more heavily tobacco-dependent patients, Dr. Prochazka said. His go-to combinations are nicotine replacement therapy (NRT) plus bupropion (Zyban), or high-dose NRT using a nicotine patch plus nicotine gum or lozenges.
There is a definite need for more studies aimed at defining the optimal drug combinations, according to Dr. Prochazka, professor of medicine at the university and acting associate chief of staff at the Denver VA Medical Center.
The third class of drugs approved by the Food and Drug Administration for smoking cessation, in addition to NRT and the antidepressant bupropion, is varenicline (Chantix), a nicotine receptor partial agonist and the first designer drug for tobacco dependence.
A Cochrane Review of the pivotal clinical trials leading to varenicline's 2006 marketing approval concluded it had a 52% better quit rate than did long-acting bupropion, and there was a suggestion of moderately greater efficacy than NRT, although there were few trials comparing the two (Cochrane Database Syst. Rev. 2008;doi: 10.1002/14651858.CD006103.pub3).
And varenicline has a relatively low discontinuation rate. But because of varenicline's psychiatric morbidity and hefty price, Dr. Prochazka reserves it as second-line therapy in patients who have failed NRT and bupropion.
The VA smoking cessation guidelines also categorize varenicline as second-line therapy.
In July, the FDA ordered a black box warning for both varenicline and bupropion, urging prescribers to watch for the development of hostility, agitation, depression, and suicidality. The VA guidelines now call for varenicline to be avoided in psychiatric patients unless the smoking cessation intervention is done in collaboration with a mental health professional. For the time being, the best approach to smoking cessation in psychiatric patients remains unclear, Dr. Prochazka said.
In a generally healthy population of smokers, however, all three FDA-approved types of medication are safe and effective, he stressed. …