A Study to Investigate the Safety, Tolerability, Pharmacokinetics and Pharmacodynamics After Oral Administration of AJH-2947 in Healthy Korean and/or Caucasian Adult Male Subjects

Inclusion criteria

• Healthy Korean or Caucasian adult males aged 19 to 55 years old, based on the date of written consent

*Caucasian subjects = Individuals born in Europe, have resided in countries outside Europe for less than 10 years, and whose parents and grandparents are all of European descent.

• Individuals with a body weight between 50.0 kg and 90.0 kg and a body mass index (BMI) ranging from 18.5 kg/m2 to less than 30.0 kg/m2

• BMI (kg/m2) = weight (kg) / {height (m)}2
• Individuals who agree to stay in the CTC ward until discharge and consent to the use of sunscreen until the end of the clinical trial (PSV)
• Individuals who have heard a detailed explanation of the trial, fully understand it, voluntarily decide to participate, and provide written consent before the screening examination
• Individuals deemed suitable by the investigator based on medical history, vital signs, 12-lead electrocardiogram (ECG), physical examination, and clinical laboratory tests performed during the screening.

Exclusion criteria

• Individuals with clinically significant diseases or a history of diseases related to the liver, kidney, nervous system, immune system, respiratory system, digestive system, endocrine system, blood/tumors, cardiovascular system, urinary system, mental disorders, etc.
• In the multiple-dose trial, individuals with skin lesions, tattoos on both forearms or show hypersensitivity or allergic reactions to capsaicin cream who may affect the pharmacodynamic evaluation of the investigational product.
• Individuals with gastrointestinal diseases (such as gastrointestinal ulcers, gastritis, gastric spasm, gastroesophageal reflux disease, and Crohn's disease) or a history of surgery that may affect the safety and pharmacokinetic evaluation of the investigational product (excluding simple appendectomy and hernia repair)
• Individuals with a medical history of hypersensitivity reactions to the main active ingredient or components of the investigational product or to drugs in the same class as the main active ingredient
• Individuals with positive results for hepatitis B (HBV) test, hepatitis C (HCV) test, syphilis (RPR) test, or HIV test conducted during screening
• Individuals who exhibited systolic blood pressure < 80 mmHg or ≥ 140 mmHg or diastolic blood pressure < 45 mmHg or ≥ 90 mmHg during vital sign measurements in the supine position after a rest period of at least three minutes
• Individuals with a history of drug abuse or who tested positive for drug abuse in the urine drug screening test
• Individuals who have taken prescription drugs or traditional herbal medicine within 2 weeks before the scheduled first dose of the investigational product or have taken any over-the-counter medicines, health-functional foods, or vitamin supplements within 1 week, or are expected to take them
• Individuals who have participated in another clinical trial (including bioequivalence studies) within 6 months before the scheduled first dose of the investigational product
• Individuals who donated blood within 2 months or donated blood components within 1 month, or received a blood transfusion within 1 month before the scheduled first dose of the investigational product
• Individuals who have consumed excessive caffeine (> 5 units/day) or cannot abstain from consuming caffeine/caffeine-containing foods (such as coffee, tea, carbonated beverages, coffee-flavored milk, energy drinks, etc.) from 3 days before the expected first dose until the end of the clinical trial (PSV)
• Individuals who engage in persistent alcohol consumption (> 21 units/week, 1 unit = 10 g of pure alcohol) or cannot abstain from alcohol consumption from 3 days before the expected first dose of the investigational product until the end of the clinical trial (PSV) (1 glass (250 mL) of beer (5%) = 10 g, 1 glass (50 mL) of soju (20%) = 8 g, 1 glass (125 mL) of wine (12%) = 12 g)
• Individuals who have smoked more than 10 cigarettes/day within the last 3 months before the scheduled first dose of the investigational product or cannot quit smoking from the screening day until the end of the clinical trial (PSV)
• Individuals who cannot refrain from consuming grapefruit-containing foods from 3 days before the expected first dose of the investigational product until the end of the clinical trial (PSV)
• Individuals who have a pregnancy planning during the entire clinical trial and up to 90 days after the last administration of the investigational product or do not agree to use one or more medically acceptable contraceptive methods. The medically acceptable contraceptive methods are as follows:

① Use of an intrauterine device with a proven failure rate by the spouse (or partner)

② Concurrent use of barrier contraception (male or female) and oral contraceptive pills

③ Self or partner's surgical sterilization (vasectomy, salpingectomy / tubal ligation, hysterectomy)

• Individuals deemed ineligible for participation in the clinical trial by the investigator based on other reasons, including results of clinical laboratory tests