Pharmacokinetic and safety study of HTD1801 and its components

This will be a single-blind, randomized, single-dose, triple-cross over (a Latin square design), single-centre study. 24 Subjects will be enrolled. Each subject will receive all three treatments in random order. At each administration day approximately 1/3 of subjects will receive treatment A, 1/3 treatment B, and 1/3 treatment C and this will switch around on the second administration day and then again on third administration day until all participants have been administered all three treatments. Screening: Subjects will be screened for the study. Eligible subjects will return for the admission to the Unit within four (4) weeks following screening. All subjects will be instructed to maintain their lifestyle and background medications, if any. Baseline: Subjects will be admitted to the Unit in the evening of Day -1. Blood draw to establish the baseline for all measured endpoints will be drawn in the morning of Day 0. Randomisation: Following the completion of all baseline assessments and draws on Day 0, eligible subjects will be randomized so that approximately 1/3 of subjects will receive treatment A, 1/3 treatment B, and 1/3 treatment C. The first dose of study medication will be then promptly administered. Drug administration and assessment periods: Each subject will receive a drug three times in random pre-determined order, single dose, separated by at least 14 days of washout. Following each administration, blood for PK and safety will be drawn and safety and tolerability assessments will be conducted over the ensuing 36 hours. Final tolerability/safety assessment: Approximately seven (7) days following the administration of the last medication, the site will follow up over the phone with the subjects regarding any tolerability or safety issue; if clinically necessary, they could be invited back to the Unit for follow up tests or evaluation.