A Phase 1 Clinical Trial to Investigate the Safety, Tolerability, and Pharmacokinetics of AS-S603 in Healthy Participants

Inclusion Criteria: * Healthy Korean adult volunteers aged 19 to 50 years at the time of screening (single dose study) * Healthy Korean or Caucasian adult volunteers aged 19 to 50 years at the time of screening (multiple dose study dose groups 1-4) * Healthy elderly Korean volunteers aged 65 to 85 years at the time of screening (multiple dose study dose group 5) * Individuals with a body weight of ≥ 50.0 kg and ≤ 90.0 kg and a body mass index of ≥ 18.5 kg/m2 and ≤ 29.9 kg/m2 at the time of screening * Individuals who have given written consent on a voluntary decision to participate and agree to adhere to the precautions after being fully informed of and completely understanding this clinical trial Exclusion Criteria: * Individuals with a clinically significant disease or history in hepatobiliary, renal, nervous, immune, respiratory, endocrine, hemato-oncology, cardiovascular, urinary system, or psychiatric disorder. * Individuals with a history of a gastrointestinal disorder or surgery that may affect the safety, pharmacokinetic and pharmacodynamic evaluation of the investigational product * Individuals who answered 'yes' to any question on the Columbia Suicide Severity Rating Scale administered at the time of screening * Individuals with hypersensitivity or a history of clinically significant hypersensitivity to AS-S603 and the same class or other drugs (aspirin, antibiotics, etc.) * Individuals with a positive result in the serology test (hepatitis B, hepatitis C, human …