The FDA has issued a safety warning based on post-market adverse event reports that there is a seizure risk several days or weeks after patients begin taking Merz Therapeutics' Ampyra (dalfampridine).
Ampyra, originally developed by Acorda Therapeutics, was approved in January 2010 to improve walking in patients with multiple sclerosis. In April 2024, Acorda announced a Chapter 11 bankruptcy filing and agreed to sell substantially all of its assets to Merz Therapeutics.
Since Ampyra is eliminated by the kidneys, patients with renal impairment may have a higher risk of seizures due to more of the drug accumulating in the blood. For this reason, the FDA is recommending that patients with moderate to severe renal impairment do not receive the drug. It is updating the label to specify that patients should have their kidney function checked before starting on the medication. Furthermore, health care professionals should carefully weigh the benefits for patients with mild renal impairment.