A Study of HS-10353 in Chinese Participants.

This is a phase I, randomized, double-blinded, placebo-controlled, both single ascending doses (SAD) study and multiple ascending dose (MAD) clinical trial to assess the safety, tolerability, and pharmacokinetics of HS-10353 tablet(s) separately in Chinese healthy and major depressive disorder (MDD) subjects. Approximately six sequential dose cohorts will be evaluated in SAD study. Sentinel dosing will be employed for the first SAD cohort to protect the subjects' safety. Escalation to the next dose cohort will be undertaken only after safety and PK data are reviewed by the Safety Review Committee (SRC) and agreement reach that it is safe to increase the dose. Each SAD cohort is dosed at approximately weekly intervals to allow adequate time for collection and review of safety and PK data. Approximately three sequential dose cohorts will be evaluated in MAD study. The total daily dose for each MAD cohort will be based on information obtained from the SAD study. Each subject will receive only one dose regimen in this study. Safety data up to Day14 (±1) in SAD and up to Day20 (±1) in MAD will be reviewed prior to the next dose level. The number of Cohorts in SAD and MAD would be adjusted based on the assessment of SRC.