Open label, single-center, four-part registration pharmacokinetic study: Part I: Pilot 2-way cross-over randomized, comparative pharmacokinetic study of a new gastro-resistant 20 mg pitolisant hydrochloride formulation versus the reference formulation, after a single 20 mg oral administration in twelve healthy subjects, in order to evaluate the adequate sample size to demonstrate the bioequivalence. Part II: One sequence cross-over, drug-drug interaction pharmacokinetic study between a proton pump inhibitor (PPI) (pantoprazole 40 mg) and a new gastro-resistant 20 mg pitolisant hydrochloride formulation in eighteen healthy subjects. Part III: Pivotal 4-way replicate design cross-over randomized, bioequivalence study of a new gastro-resistant 20 mg pitolisant hydrochloride formulation versus the reference formulation, after single oral 20 mg administration in healthy subjects. Part IV: 2-way cross-over randomized, food effect study of a new gastro-resistant 20 mg pitolisant hydrochloride formulation administered under fasting conditions and after a standard FDA High Fat Breakfast in eighteen healthy subjects.