This is a first in human Phase 1 study to evaluate the safety, tolerability and pharmacokinetics with healthy young and elderly adult male volunteers after receiving single and multiple ascending dose of BEY2153.

Healthy young and elderly adult volunteers who meet the criteria, will be treated single and multiple ascending dose of BEY2153 or placebo orally. Food effect evaluation study will be conducted with single ascending dose. After the single ascending dose study, independent external experts will review blinded data and multiple ascending dose study will be conducted.

Inclusion Criteria:

1. Young adult: A healthy Korean male aged 19 to 45 (inclusive) years at the time of screening Elderly adult: A healthy Korean male aged over 65 (inclusive) years at the time of screening"
2. Subjects weighing between 55 kg and 90 kg with BMI between 18.0 and 27.0 kg/m2 (inclusive) at screening.
3. Subjects who have listened to the detailed description of this clinical trial and have fully understood, and who have agreed in writing to voluntarily participate and observe the precautions prior to receiving any of the screening procedures
4. Subjects who is eligible for this clinical trial by the investigator's judgement with laboratory test results and physical-examination findings and etc.

Exclusion Criteria:

1. Young adult / Elderly adult: Subjects with evidence or a history of clinically significant hepatic, renal, neurologic, immunologic, pulmonary, endocrine or hematological, neoplastic, cardiovascular, psychiatric diseases (mood disorder, obsessive-compulsive disorder etc.).
2. Subjects with evidence or a history of gastrointestinal disease or with history of gastrointestinal surgery that may affect assessment of safety, PK characteristics of study drug.
3. Subjects who showed significant abnormalities at neurologic examination at screening visit.
4. Subjects who showed any abnormalities at vital signs
5. Subjects who showed any abnormalities at blood test
6. Subjects with serum AST (SGOT) or ALT (SGPT) level or total bilirubin exceed 1.5 times the upper limit of the normal range at screening
7. Subjects who showed any abnormalities at ECG subsection
8. Subjects who are hypersensitive to drugs, or who have clinically significant hypersensitivity reactions history.
9. Subjects with a history of alcohol or drug abuse or subjects who showed positive results for abuse drug at urine drug screening test.
10. Subjects who consume alcohol continuously or who are unable to abstain from drinking from the time of consent until the end of the clinical trial.
11. Smokers
12. Subjects who had recessive disease, symptomatic infection, virus, bacteria or fungus infection 1 week before the first study drug administration.
13. Subjects who have taken any prescribed drug or herbal medicine within two weeks prior to the first study drug administration. Non-prescribed medicine (OTC) or vitamin supplement prohibit within one week prior to the first study drug administration or subjects whose administrations are predicted.
14. Subjects who have participated and taken investigational drug in any other clinical trial within six months prior to study drug administration
15. Subjects who showed positive result for HBs antigen, HCV antibody, HIV antigen-antibody test at screening
16. Subjects who had whole blood donation, apheresis or blood transfusion within 3 months before the first study drug administration.
17. Subjects who had grapefruit containing food from 3 days before the scheduled date of the first study drug administration to discharge and those who cannot be prevented from taking it during the study period.
18. Subjects who consume or are unable to abstain from products containing caffeine from 3 days before the scheduled date of the first study drug administration to discharge, and those who cannot be prevented from taking it during the study period.
19. Subjects who do not agree to use following medically appropriate method of contraception and not to donate sperm starting from subject enrollment to 90 days after last administration of investigational product.
20. Subjects judged ineligible for the study after a review of the clinical laboratory results by the investigator or for other reasons.