The purpose of this study is to investigate the safety, tolerability, and pharmacokinetics of 3 escalating loading and maintenance dose regimens of CG100649 administered orally for 7 total days in healthy volunteers.

Data dictionary that contains detailed descriptions of each variable used by the registry, including the source of the variable, coding information if used CTCAE and normal ranges if relevant.

Inclusion Criteria:

1. 19-55 years old. Body weight is over 50 kg (male) and over 45 kg (female). Body weights must be within 20% of ideal body weight for their height according to the ideal body weight table.
2. No significant congenital/chronic disease. No symptoms in physical examination.
3. Appropriate subjects as determined by past medical history, laboratory tests, serology and urinalysis.
4. Be able to understand the objective, method of the study, the characteristics of investigational drug, and comply with the requirement of the study. Subject must provide written informed consent prior to study participation.

Exclusion Criteria:

1. History or presence of liver, kidney, or nervous system disease, respiratory disorders, endocrinological disorders, hemato-oncologic, cardiovascular or psychiatric or cognitive disorders.
2. History of gastrointestinal disorders (bleeding, ulceration, hemorrhoids, piles) or disorders of absorption, distribution, metabolism, excretion.
3. History of known hypersensitivity to drugs including CG100649.
4. After taking a rest in sitting position for 3 minutes, subjects who have low blood pressure (Systolic BP ≤ 90 mmHg or Diastolic BP ≤ 50 mmHg) or high blood pressure (Systolic BP ≥ 150 mmHg or Diastolic BP ≥ 100 mmHg).