The study has been largely funded by the Food and Drug Administration (FDA). The administration has previously produced guidelines to make sure that the generic version of a drug is virtually identical to its branded counterpart. These guidelines allow a certain margin of difference, within which a generic drug is supposedly just as effective.
Reports from people with epilepsy who have been switched from one to another disagree, however. Many people have said that they experienced a change in their seizure control when moving between branded and generic versions of a drug, or between generic versions.
The new study is led by Prof Michael Privitera. He says: “The FDA, last year, decided they would fund the study to look at how much difference there is between generic drugs and brand name drugs.
“Some doctors and some patients have complained that when [people with epilepsy] switch from the brand name drug to the generic drugs that they were losing control of the seizures or they were having too many side-effects.”
Ultimately, whatever the outcome, the study should mean that people with epilepsy in the US can expect a more consistent approach to their treatment in future. It is unclear at this stage whether any changes in America will then be reflected in UK treatment.
The study will take between 15 and 18 months to complete and is being carried out at a number of different sites. The FDA has given an impressive $1.6 million funding to the project. Another $1 million will come from the American Epilepsy Society and the Epilepsy Foundation, each having donated $500,000.
Branded or generic: what’s what?
When a drug company develops a new drug, they apply for a licence to market that drug for a particular use, such as treating seizures. Developing the drug can be a very expensive process – so, once the drug is licensed, only that company is permitted to manufacture and sell it. That way, they can get back the money spent on drug development.
This original drug formula is sold under a specific brand name, so that the drug is what we call a branded drug. For instance, eslicarbazepine acetate is the name of an epilepsy drug that is sold under the brand name ‘Zebinix’.
However, the licence to be the only company making a certain drug only lasts for between 10 and 12 years. After this time, it is legally possible for other manufacturers to start manufacturing their own version of the drug formula. These new versions are referred to as ‘generic’ drugs.
According to guidelines, these generic versions are only permitted to be very slightly different in formulation to the original. The long-running debate here is based on stories that even these tiny differences can affect seizure control.