The Medicines and Healthcare Products Regulatory Agency (MHRA) has issued new guidance to prescribers, pharmacists and patients in relation to anti-epileptic drugs (AEDs). This follows a review by the Commission on Human Medicines (CHM) which looked at the evidence on patients switching between different manufacturers’ products of particular AEDs. CHM concluded that whilst there was no clear evidence of harm associated with switching products, an effect in some patients, for some drugs, could not be completely ruled out. The potential effects of switching may include a loss of seizure control or the occurrence of side effects, or both. These risks can be associated with switching between a branded originator and a generic product, and between different generic products.
CHM advised that AEDs could be classified into three categories. These categories aim to help prescribers and patients decide whether it was necessary to maintain continuity of supply of a specific manufacturer’s product.
For these drugs doctors are advised to ensure that their patient is maintained on a specific manufacturer’s product.
The AEDs in this category are: phenytoin, carbamazepine, phenobarbital, primidone.
For these drugs the need for continued supply of a particular manufacturer’s product should be based on clinical judgement and consultation with patient and/or carer taking into account factors such as seizure frequency and treatment history
The AEDs in this category are: valproate, lamotrigine, perampanel, retigabine, rufinamide, clobazam, clonazepam, oxcarbazepine, eslicarbazepine, zonisamide, topiramate.
For these drugs it is usually unnecessary to ensure that patients are maintained on a specific manufacturer’s product unless there are specific concerns such as patient anxiety, and risk of confusion or dosing errors.
The AEDs in this category are: levetiracetam, lacosamide, tiagabine, gabapentin, pregabalin, ethosuximide, vigabatrin.
Dr Siu Ping Lam, the MHRA’s Acting Director of Licensing said: “This is important new advice in relation to drugs for the treatment of epilepsy. The categories of anti-epileptic drugs are designed to help healthcare professionals decide upon whether it is necessary to maintain continuity of supply of a particular manufacturers’ product. If patients have any concerns about, or problems with, their antiepileptic medicine, they should speak to a healthcare professional such as a doctor, pharmacist, or nurse.”
Notes to Editor
1. Related link: Antiepileptics: changing products
2. The MHRA is responsible for regulating all medicines and medical devices in the UK by ensuring they work and are acceptably safe. Underpinning all our work lies robust and fact-based judgements to ensure that the benefits justify any risks. The MHRA is a centre of the Medicines and Healthcare Products Regulatory Agency which also includes the National Institute for Biological Standards and Control (NIBSC) and the Clinical Practice Research Datalink (CPRD). The MHRA is an executive agency of the Department of Health.