[Therapeutic drug monitoring of stiripentol]

Stiripentol is a third generation antiepileptic, marketed since 2007 under the name of Diacomit(®). It is indicated, always in combination, in the treatment of severe myoclonic epilepsy in infancy or Dravet syndrome. Its pharmacokinetics is not linear. It is a potent inhibitor of CYP3A4, 1A2 and 2C19 and increases the plasma concentrations of many other antiepileptic drugs. Without this being considered as a validated therapeutic range, the trough plasma concentrations at steady-state, corresponding to the usual doses are between 10 and 15 mg/L. The concentration-efficacy relationship is not established, but there is some evidence for a concentration-related toxicity. However, because of its non-linear kinetics, stiripentol should be a good candidate for therapeutic drug monitoring (TDM). Nonetheless, the current level of evidence for the advantage of TDM is "remains to be estimated".