Clinical Research Directory

Inclusion Criteria: * Subjects voluntarily agree to participate and sign an informed consent form (ICF) before any study procedures begin. * Male and female healthy subjects aged 18 to 55 at the time of signing the ICF. * Male weight ≥ 50.0kg, female weight ≥ 45.0kg; Body Mass Index (BMI)=Weight (kg)/Height² (m²), within the range of 19.0\~26.0 kg/m². * Female subjects with fertility tested negative for pregnancy during the screening period. * The subjects are able to communicate well with the investigator and understand and comply with the requirements of this study. Exclusion Criteria: * Allergies to AK139 components and any monoclonal antibodies. * Positive results of confirmatory serology test for hepatitis B, hepatitis C,HIV or syphilis at screening. * have participated in any drug clinical study within 3 months prior to randomization, or are still within 5 half-lives after the last administration of other investigational drugs (whichever is longer) * Previously or currently suffering from any diseases of the circulatory, endocrine, neurological, digestive, respiratory, urogenital, blood, immune, psychiatric, or metabolic systems that may interfere with the test results. * History of parasitic infection. * Drug abusers or individuals with positive urine drug results during screening. * Have donated blood or experienced significant blood loss, received blood transfusions, or used blood products 3 months before screening. * Investigator assessed that it is not suitable to participate in the study.