Monday, December 17, 2012

FDA: Use of Varenicline Associated With Higher Risk of Cardiovascular Events

Be careful what you use for smoking cessation.
http://www.docguide.com/fda-use-varenicline-associated-higher-risk-cardiovascular-events
A higher occurrence of major adverse cardiovascular events (a combined outcome of cardiovascular-related death, nonfatal myocardial infarction [MI], and nonfatal stroke) was observed in patients using varenicline (Chantix) to aid in smoking cessation, compared with placebo, according to a meta-analysis conducted by the US Food and Drug Administration (FDA).
The FDA required the manufacturer of varenicline to conduct the meta-analysis to further evaluate the cardiovascular safety of the drug, and believes it is important to let healthcare professionals and patients know about the results of this study.
Cardiovascular events were uncommon in both the varenicline and placebo groups, and the increased risk was not statistically significant, which means it is uncertain whether the excess risk for the varenicline group was due to the drug or due to chance.
However, the data were analysed many different ways and consistently showed a higher occurrence of events in patients using varenicline, which makes it seem more likely that it is related to the drug and not purely a chance finding.
Healthcare professionals are advised to weigh the risks of varenicline against the benefits of its use. It is important to note that smoking is a major risk factor for cardiovascular disease, and varenicline is effective in helping patients to quit smoking and abstain from it for as long as 1 year. The health benefits of quitting smoking are immediate and substantial.
Patients taking varenicline should contact their healthcare professional if they experience new or worsening symptoms of cardiovascular disease, such as chest pain, shortness of breath, calf pain when walking, or sudden onset of weakness, numbness, or difficulty speaking.
Data Summary
The meta-analysis incorporated data from 7,002 patients (4,190 Chantix and 2,812 placebo) that were enrolled in 15 Pfizer-sponsored, randomised, double-blind, placebo-controlled clinical trials lasting ≥12 weeks.
The primary cardiovascular safety assessment included an analysis of the occurrence and timing of major adverse cardiovascular events (MACE). The MACE composite outcome included the following endpoints: cardiovascular-related death, nonfatal MI, and nonfatal stroke. Cardiovascular events included in this composite outcome were adjudicated by a blinded, independent committee.
Overall, there was a low incidence of MACE occurring within 30 days of treatment discontinuation (0.31% for varenicline vs 0.21% for placebo). Exposure to varenicline resulted in an adjusted hazard ratio of MACE of 1.95, which is based on trials reporting at least 1 MACE. This is similar to an estimated increase of 6.3 MACE per 1,000 patient-years of exposure.
The meta-analysis also showed higher rates of composite outcomes in patients on varenicline relative to placebo across different time frames and pre-specified sensitivity analyses, including various study groupings, and cardiovascular endpoints. Although these findings were not statistically significant, they were consistent. Because the number of adverse cardiovascular events was small overall, the power for finding a statistically significant difference in a signal of this magnitude is low.
It should be noted that the incidence of cardiovascular mortality (0.05% for varenicline vs 0.07% for placebo) and all-cause mortality (0.14% for varenicline vs 0.25% for placebo) was lower in the varenicline group compared with the placebo group, although this finding was also not statistically significant.
Adverse events should be reported to the FDA:
1-800-332-1088
1-800-FDA-0178 Fax
Mail to: MedWatch 5600 Fishers Lane
Rockville, MD 20857
SOURCE: US Food and Drug Administration
 

No comments:

Post a Comment