A randomized, double-blind, placebo-controlled, single-ascending dose Phase Ⅰa study to evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of STSA-1002 following intravenous infusion in healthy subjects

Inclusion Criteria:

• Healthy subjects, aged ≥ 18 but ≤ 65, male and female;
• Body mass index: 18.0 -25.0 kg/m2, inclusive;
• Subjects (including their partners) agree to take highly effective contraceptive measures during the study, and they have no birth plan or sperm donation plan within 5 months after the end of the study;
• Medical histories, physical examinations, laboratory examinations and study-related examinations and tests of the subjects show normal results or mild abnormalities with no clinical significance before enrollment, and the Investigator judges that they are eligible;
• Subjects are aware of the risks of the study, and voluntarily participate in the clinical study and sign an informed consent form (ICF).

Exclusion Criteria:

• Past history of tuberculosis, history of contact with active tuberculosis, and positive tuberculin test results;
• History of cardiovascular, respiratory, kidney, liver, metabolism, endocrine, gastrointestinal, blood, nerve, skin and mental illness, cancer or other major disease that in the judgment of the Investigator might put the subject as risk on this study;
• There is a clear history of food or drug allergy or the total serum immunoglobulin IgE is higher than the upper limit of normal;
• Positive screening test results for human immunodeficiency virus (HIV-1/HIV-2) antibodies, hepatitis B surface antigen (HBsAg) or hepatitis C antibody (HCVAb);
• Presence of clinically significant vital signs values or of electrocardiogram (ECG) abnormalities during the screening period, as defined by an Investigator;
• ANA positive;
• During the screening period, the white blood cell count and C-reactive protein test results are abnormal and have clinical significance, hemoglobin: male <120g/L or female <110g/L;
• Smoking more than 5 cigarettes per day or equivalent amount of tobacco in the 3 months before screening;
• Subjects whose daily consumption of alcohol at the time of screening or at any time within the prior 6 months is more than 2 standard drinks, where 1 standard drink = 355 mL or 12 oz (1 can) of regular-strength (5%) beer; 150 mL or 5 oz wine; 45 mL or 1.5 oz liquor/spirits (40%);
• Subjects who had a history of drug abuse or tested positive for drugs within 1 year before screening;
• Subjects who have donated either more than approximately 500 mL of blood (exclusive plasma donation) within 3 mooth prior to screening or any plasma within 4 weeks prior to screening;
• Participate in any drug or vaccine clinical trial as a subject within 3 months before screening or prepare to be vaccinated during the study period to 2 months after the end of the study;
• Have taken drugs that may affect immune function within 6 months before screening or have received any monoclonal antibody or biological agent treatment within the previous 3 months and have taken prescription/over-the-counter drugs, herbal medicines, vitamins or other supplements within the previous 14 days;
• Drink more than 5 cups of coffee, tea or cola per day (150ml and above per cup);
• Women who are pregnant or breastfeeding;
• People with a history of fainting, bleeding and needles;
• The investigator believes that there are any subjects who are not suitable to participate in this trial.