Foundation Opposes Mandatory Substitution for Antiepileptic Drugs
The Epilepsy Foundation has had a historical position opposing mandatory substitution of generic drugs for brand name since generics first became available because of concerns about reported breakthrough seizures in some people with epilepsy when they are switched from one version of a medication to another. Other medical organizations focused on the treatment of epilepsy have had similar positions.
The concern centers on several issues, not just the extreme consequences of having breakthrough seizures.
Is the therapeutic range accepted by the FDA to show “bioequivalence” of a generic version with a brand name drug too broad, allowing for too much variability in levels of the product that controls the seizures? The FDA has recognized that some epilepsy drugs had a “narrow therapeutic index,” and therefore the generic version could not be substituted without the agreement of the physician and the patient.
Is there something about the nature of antiepileptic drugs that creates problems with switching among versions of a drug?
What is the impact of the “bioavailability” of the medicine? In other words, while chemically a brand name and generic version drug are similar, are there differences in the way a body processes the drugs because of other ingredients used to make the two drugs?
These questions continue to be concerns today.
Data and Research on Problem of Substitution and Switching Is Scarce
The Epilepsy Foundation last issued its statement opposing mandatory substitution and switching among versions of a drug in 1996. Since then there has been more experience with the use of generics, particularly internationally where generic versions of drugs are commonly used. Some medical societies in other countries have taken a position restricting generic substitution and switching for epilepsy medications when someone’s seizure control is stable on a brand name drug.
Anti-Epileptic Generic Substitution Data and Policy Review
Many newer epilepsy drugs introduced in the 1990s will soon have generic versions available in the United States. In order to update its ten year old position, and address growing concerns that switching problems previously identified are likely to occur again with potential serious harm to patients, the Epilepsy Foundation has begun reviewing all available literature and data, including physician and consumer surveys, in order to produce public policy and research recommendations by early 2007.
New developments will be reported as they arise.
