The FDA has updated the label for varenicline (Chantix) to include additional information about the safety and efficacy of the smoking cessation drug in patients with cardiovascular disease or chronic obstructive pulmonary disease (COPD).
The label update follows an FDA statement last month noting that it was reviewing reports that use of the drug was associated with an increase of recurrent myocardial infarction or new onset peripheral arterial disease.
FDA said that a randomized trial of 700 smokers with stable cardiovascular disease found that participants who received varenicline were twice as likely to quit smoking and to stay smoke-free for a year versus participants in the placebo arm. The varenicline dose was 1 mg twice daily for 12 weeks.
The FDA said that information was added to the drug label, but also noted that the same study "demonstrated that Chantix may be associated with a small, increased risk of certain cardiovascular adverse events in these patients." The agency said the absolute risk of cardiovascular events with the drug was small in relation to its efficacy.
The new label also contains information about the utility of varenicline in COPD patients. This information reflects an FDA analysis of findings from a clinical trial of varenicline in 460 patients with mild to moderate COPD. Patients were randomized to varenicline (1 mg bid) or placebo for 12 weeks and then followed for 40 weeks.
The FDA said results from that trial showed that varenicline "was more effective in helping COPD patients quit smoking, and remain abstinent from smoking, for as long as one year compared to placebo. Adverse events in this clinical trial were similar to those seen in studies that were conducted for Chantix's initial approval in 2006, and no new safety concerns were identified."
Finally, the FDA updated the varenicline label to provide alternative directions for patients "who select a quit smoking date after they have already started taking Chantix."
For those patients, the FDA said the new label stipulates that they should start taking varenicline seven days before their quit date or, alternatively, begin the drug and then quit smoking between day eight and day 35 of treatment.
