Comtan, Stalevo Not Linked To Cardiovascular Risks: FDA

Following a drug safety review that examined the potential cardiovascular side effects of the Parkinson’s disease drugs Comtan and Stalevo, federal regulators indicate that they found no clear evidence that users may face an increased risk of heart attacks. 

The FDA issued a drug safety communication on October 26, announcing the results of a review that started with Stalevo heart concerns in August 2010.

Stalevo (entacapone/carbidopa/levodopa) is a prescription drug by Novartis used to treat dyskinesia (movement disorder) associated with the onset of Parkinson’s disease. The drug was approved by FDA in June 2003, and an estimated 154,000 people have been prescribed the drug since it hit the market. Side effects of Comtan (entacapone) were also examined, as it contains one of the two active ingredients in Stalevo.

Concern over the Stalevo heart side effects stem from a meta-analysis of 15 clinical trials, which suggested that the medication may increase the risk of heart attack, stroke and cardiovascular death among users. However, the FDA indicates that the clinical trials were not designed to look for heart problems from Stalevo and that the majority of the patients already had an increased risk of cardiovascular disease. Parkinson’s disease is also known to often increase the risk of heart attack and stroke.

An earlier study, known as Stalevo Reduction In Dyskinesia Evaluation – Parkinson’s Disease (STRIDE-PD), looked at 373 patients using Stalevo and 372 patients being given the drug combination of carbidopa and levodopa. In that study, eight Stalevo patients suffered heart attacks, one of whom died. No patients from the other group suffered heart attacks.

“The results observed in the original meta-analysis were driven by the results of a single study (STRIDE-PD), which was not designed to assess cardiovascular risks,” the FDA review determined. “We believe that the meta-analysis and STRIDE-PD results are chance findings and do not represent a true increase in risk due to entacapone.”

Two additional studies, one by independent researchers and one by Novartis, failed to find any link between side effects of Stalevo or Comtan and an increased heart attack risk.

“In light of the results from these two additional studies, FDA finds no evidence of an increased risk of myocardial infarction, stroke, or other cardiovascular events associated with the use of entacapone, Comtan or Stalevo,” the agency concluded. “As a result, the drug labels will remain unchanged.”