The purpose of the study is to evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics, and immunogenicity of a single dose of UB-221 in healthy volunteers.

This is a phase I, open-label, dose-escalation study to evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics,and immunogenicity of a single dose of UB-221 in healthy volunteers.

Inclusion Criteria:

• Subjects with age between 20 to 65 years old (inclusive).
• Subjects who are able and willing to provide the informed consent.
• Male subjects with body weight of 50 kilogram (kg) or above; female subjects body weight of 45 kilogram (kg) or above.
• Researchers based on medical history, physical examination, vital signs, clinical laboratory results and 12-lead electrocardiogram identified healthy subjects without clinically significant abnormalities

Exclusion Criteria:

• The investigator considered that the subjects were not suitable to participate in this study.