FDA to Consider Tighter Standards for Generic Epilepsy Drugs

Studies on drug pharmacokinetics in epilepsy patients are being conducted to help the US Food and Drug Administration (FDA) consider whether it needs to tighten bioequivalence rules for generic anti-epilepsy drugs (AEDs) and other medications that have narrow therapeutic windows, according to a press briefing held at the American Epilepsy Society (AES) annual meeting in Washington, DC.

AES Vice President Michael Privitera, MD, said preliminary evidence from open-label studies and analyses of generic manufacturers’ bioequivalence data led the FDA to agree that more clinical trials are needed to examine the issue. The FDA has provided funding to conduct those studies — 2 of which involve brand-name lamotrigine and its generic versions — and the results should be available next year.

Privitera said the FDA may consider a new bioequivalence standard of 90-111% for certain narrow-index drugs if new studies support it.