Estimated impact for the NHS

Estimated impact for the NHS

Likely place in therapy

Zonisamide as adjunctive therapy for partial (focal) seizures in epilepsy was considered during the development of the NICE clinical guideline on epilepsy. Based on evidence that was available at the time (up to June 2010), the Guideline Development Group found that zonisamide was one of several anti-epileptic drugs that were more costly and less effective than other cost-effective treatment alternatives. However at the time of publication of the guideline (January 2012), zonisamide did not have UK marketing authorisation for use in children and young people aged less than 18 years.

The NICE clinical guideline on epilepsy, advises that if first-line treatments are ineffective or not tolerated, adjunctive treatment with carbamazepine, clobazam, gabapentin, lamotrigine, levetiracetam, oxcarbazepine, sodium valproate or topiramate should be offered to children, young people and adults with partial (focal) seizures.

The guideline advises that if standard adjunctive treatment is ineffective or not tolerated, decisions about treatment options should be made after advice from a tertiary epilepsy specialist. Efficacy, cost, safety and individual patient factors will all influence the decision to use a particular adjunctive anti-epileptic drug in each person. Although no studies are available comparing zonisamide with other anti-epileptic drugs, the European Medicines Agency (EMA) states that the efficacy of zonisamide appears similar to other anti-epileptic drugs already indicated for adjunctive use in children.

Estimated usage

It is not possible to estimate usage of zonisamide based on the available data; however, it is likely that zonisamide may provide an additional licensed treatment in a proportion of children and young people with partial seizures that are refractory to current treatment.