FDA Warning About Risk of Seizures with MS Drug fampridine
A warning has been issued by the U.S. Food and Drug Administration (FDA) regarding an increased risk of seizures in individuals with MS, treated with fampridine (Ampyra®), developed by Acorda Therapeutics Inc.
Ampyra (or Fampyra as it is known in Canada) was approved by the FDA in January 2010 to improve walking in individuals with MS. A known side effect of Ampyra, are seizures which have an increased risk of occurring with higher blood levels of the drug. The FDA is currently updating the drug label to advise that kidney function should be checked before starting Ampyra; and monitored once a year during the course of the treatment. Kidney impairment may cause an elevated blood level of the drug, which can increase the risk of seizures.
Individuals who miss a dose are advised not to take an additional dose of Ampyra as it may increase the risk of seizures. Information collected from post-market adverse event reports show that the majority of seizures occurred within days to weeks after starting the recommended dose, in patients with no previous history of seizures. Most people who experienced seizures with the use of this drug were at least 50 years old, which is also the age where a decline in kidney function is common.
The communication from the FDA also mentions that the benefits of Ampyra should be carefully considered along with the possible risk of seizures before being used by individuals with minor kidney impairment.