A Phase 1, Open‐Label, Pharmacokinetic Trial to Investigate Possible Drug‐Drug Interactions Between Clobazam, Stiripentol, or Valproate and Cannabidiol in Healthy Subjects

Abstract GW Pharmaceuticals’ formulation of highly purified cannabidiol oral solution is approved in the United States for seizures associated with Lennox‐Gastaut and Dravet syndromes in patients aged ≥2 years, for which clobazam, stiripentol, and valproate are commonly used antiepileptic drugs. This open‐label, fixed‐sequence, drug‐drug interaction, healthy volunteer trial investigated the impact of cannabidiol on steady‐state pharmacokinetics of clobazam (and N‐desmethylclobazam), stiripentol, and valproate; the reciprocal effect of clobazam, stiripentol, and valproate on cannabidiol and its major metabolites (7‐hydroxy‐cannabidiol [7‐OH‐CBD] and