Correction: A previous version of the article below indicated that advocacy groups are calling for a black box warning on the Chantix label. In fact, Pfizer has already updated the label with a boxed warning.
Pfizer Inc. (PFE) said Wednesday that significantly more smokers with mild-to-moderate chronic obstructive pulmonary disease, or COPD, undergoing Chantix/Champix, or varenicline, treatment quit smoking compared with placebo. The findings from the study was presented at American College of Chest Physicians annual meeting.
Chronic obstructive pulmonary disease (COPD) refers to chronic bronchitis and emphysema, a pair of two commonly co-existing diseases of the lungs in which the airways become narrowed. More than 12 million people in the United States are diagnosed with COPD, and 80-90% of them are smokers. COPD is a major cause of disability, and it's the fourth leading cause of death in the United States.
The Pfizer-sponsored study was a multicenter, double-blind, placebo-controlled trial, enrolling 499 adults suffering from mild-to-moderate COPD, who had smoked an average of 10 cigarettes or more per day in the year before enrollment. Achieving smoking cessation in 12 week treatment and evaluation of abstinence from smoking for the 40 weeks after the treatment period was the primary efficacy objective. The safety objective was to gather safety data for 12 weeks of treatment with varenicline or placebo.
The study data during the last four weeks of treatment, being weeks 9-12, revealed at p<0.0001, that="" 42.3%="" of="" chantix/champix="" treated="" smokers="" were="" able="" to="" quit="" smoking="" and="" remain="" abstinent="" compared="" with="" 8.8%="" of="" those="" given="" placebo.="" at="" the="" end="" of="" 52="" weeks,="" 18.6%="" of="" participants="" who="" took="" varenicline="" remained="" abstinent,="" compared="" with="" 5.6%="" of="" participants="" randomized="" to="" take="">
Varenicline was generally well-tolerated in the study, with treatment-emergent serious adverse events of 2.8% in varenicline-treated group versus 4.4% in placebo. The most common adverse events reported in the study were nausea, abnormal dreams, upper respiratory tract infection, insomnia, headache, flatulence and vomiting.
Pfizer's Chantix, launched in May 2006, faced safety concerns, as smoking cessation drugs were reported to have serious side effects including suicide and depression.
In July, in agreement with the FDA, Pfizer updated the Chantix label to communicate important safety information in a boxed warning as well as in revised warnings and precautions, based on post-marketing reports.
In the recent third-quarter, Chantix recorded revenue reduction of 15% year-over-year, to $155 million from $182 million, contributed by a 22% and 7% decline in the U.S. and rest of the world, respectively.
"Quitting smoking is of paramount importance for all smokers, particularly those with a smoking-related illness, such as COPD. This study shows that varenicline is an effective means of smoking cessation for a highly nicotine-dependent, difficult-to-treat group of patients. The safety profile of varenicline in this study was consistent with its pre-approval clinical trials," noted Dr. Donald Tashkin, study investigator, emeritus professor of medicine at University of California, Los Angeles.
PFE closed Wednesday's trading at $16.93, on the NYSE.
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