The FDA issued a warning that Mirapex (Pramipexole) may carry an increased risk for developing heart failure.
Results of recent studies suggest a potential risk of heart failure that needs further review of available data..
The agency did caution that it has not concluded that the drug used to treat Parkinson’s disease and restless leg syndrome increases the risk of heart failure.
The FDA is currently working with the manufacturer of Mirapex, Boehringer Ingelheim. The FDA cannot, with the data available and the study limitations, determine whether Mirapex really does raise the risk of heart failure. The Agency says it is working with the manufacturer to determine the risk of Mirapex associated heart failure.
Clinical Trial Analysis: Mirapex Heart Failure Safety Signal
After gathering and examining data from randomized trials, the FDA found more cases of heart failure (12 of 4,157 patients) among patients treated with pramipexole than among those on placebo (4 of 2,820). The Agency stressed that the difference was “not statistically significant”.
In two studies using data from Europe found the increased risk of Mirapex heart failure was statistically significant. In one of the studies, a case control study using a database of patients aged 40-89 years treated with anti-parkinsonian drugs, the risk of heart failure associated with any use of a dopamine agonist compared with no use was increased by almost 60% (relative risk, 1.58). The Mirapex heart failure risk relative risk was 1.86 and 2.07 with another dopamine agonist cabergoline. Both of these risks were higher compared with no use of these drugs.
In other study, Mirapex heart failure was increased compared with levodopa. The risk was increased in the first 3 months of treatment and among patients aged 80 years and older, but was no higher among people who had been treated with pramipexole for more than 3 months.
This last finding is “difficult to explain,” since heart failure is a chronic condition, and the studies had limitations, which “make it difficult to determine whether excess heart failure was related to Mirapex use or other influencing factors,” the FDA statement said.
Mirapex was approved in July 1997 and is a member of a class of medicines called dopamine agonists. It is also used off-label for treating cluster headaches and sexual dysfunction. Some pilot studies found that Mirapex is better than placebo in controlling some of the symptoms of bipolar disorder. Mirapex is also being investigated for the treatment of fibromyalgia and depression.
Doctors are being asked to carry on following the recommendations in the drug label when prescribing MIrapex (pramipexole). All patients on pramipexole should continue taking it according to their doctors’ instructions, the FDA urged. If you have any doubts concerning pramipexole, ask your health care professional.