The objective of this study is to evaluate the safety and pharmacokinetic profiles of HHT201 in healthy subjects.

The study aims to evaluate the safety, pharmacokinetics and to determine the potential dose limiting toxicity of HHT201 in healthy subjects between the ages of 20-59, 6 in 17mg dose group and 20 in 34mg dose group. Another 12 subjects will be administered a tablet of 5mg Donepezil Hydrochloride to get the PK profile of Donepezil as reference. Eligible subjects will be accepted into the protocol after review and providing voluntary written informed consent forms and completion of a comprehensive medical, physical examination, and routine laboratory assessment.

Inclusion Criteria:

• Chinese healthy subjects, male or female
• between the ages of 20 and 60 years
• A body mass index (BMI), calculated as weight in kg/(height in m)², from 19 to 28 kg/m², and female weight≥45kg, male weight≥50kg
• Able to provide written informed consent forms

Exclusion Criteria:

1. Clinically significant history of gastrointestinal, cardiovascular, musculoskeletal, endocrine, hematologic, psychiatric, renal, hepatic, bronchopulmonary, neurologic, immunologic, lipid metabolism disorders
2. Resting pulse rate <55/min or >100/min; Sitting systolic blood pressure <90mmHg or >140mmHg, diastolic blood pressure <60mmHg or >90mmHg
3. ALT or Cr, BUN exceeding the upper limit of normal value; test results of urine protein was "++"
4. Clinically significant ECG abnormalities in screening or baseline, such as male QTc interval ≥450ms and female QTc interval ≥470ms, and were considered inappropriate for inclusion by the researchers
5. Positive blood screen for human immunodeficiency virus (HIV), hepatitis B surface antigen (HBsAg), or hepatitis C antibody
6. History or presence of drug or alcohol abuse
7. Positive pregnancy test result, or plan to be pregnant if female
8. An unwillingness or inability to comply with food and beverage restrictions within 24 hours prior to dosing
9. Participation in any other investigational drug trial within 30 days prior to screening.