This study is to evaluate the safety, tolerability, and pharmacokinetics of YR001 topical ointment in healthy adult subjects.

Inclusion Criteria:

1. Written informed consent obtained from the subject
2. Male or female subject is aged between 18 and 65 years
3. Subject has a weight of at least 50 kg and a body mass index (BMI) between 18.0 and 30.0 kg/m2
4. Free from any clinically relevant illness or disease incl. skin disorder that may adversely affect the safety of the subject or the integrity of the study

Exclusion Criteria:

1. Presence or history of a clinically significant medical condition or other condition that might interfere with the safety, tolerability and PK assessment of ointment YR001, or place the subject at an unacceptable risk as a subject in this study.
2. Pregnant or lactating women.
3. Any skin tattoo, scar, cuts, bruises, or other skin damage, including excessive UV exposure, at the possible IP application sites.
4. Have concomitant skin disease or infection (e.g., acne, impetigo) or presence of skin comorbidities in the skin areas to be dosed that may interfere with study assessments and treatment response.
5. Have active infectious disease.
6. Subjects treated with another investigational drug, biological agent, or device
7. Participation in another interventional clinical trial before entering, or during the trial, or previous participation in this clinical trial.
8. Evidence of clinically important cardiac conduction abnormalities at screening as judged by ECG.
9. Active untreated mental or psychiatric disorder.
10. Any major surgery within 6 months of screening.
11. Malignancy within 5 years, except for basal or squamous cell carcinoma of the skin or carcinoma in situ of the cervix that has been successfully treated.

13. Drug or alcohol abuse history.