Which of the following is granted orphan drug status for the treatment of Dravet’s syndrome?

Stiripentol Stiripentol increases GABA transmission. It is granted orphan drug status for the treatment of Dravet’s syndrome (Severe myoclonic epilepsy in infants). Icatibant is a bradykinin B2 receptor antagonist. It is used for acute attacks of hereditary angioedema in adults with C1-esterase inhibitor deficiency. Pitolisant (a/k/a Tiprolisant) is a inverse agonist of H3 receptor. It is under trial for schizophrenia and Parkinson’s disease. Tafamidis stabilizes the correctly folded tetrameric form of TTR. It is used in familial amyloid polyneuropathy.