A Study of TQH2722 Injection to Evaluate the Safety, Tolerability, Pharmacokinetics, Efficacy and Immunogenicity in Healthy Adult Subjects

Inclusion Criteria:

• 1 The informed consent was signed before the trial, fully understood the purpose andprocess of the trial and the possible adverse reactions.
• 2 Aged 18 ~ 60 years old (including the critical value), both male and female;
• 3 ≥ 45 kg for females and ≥ 50 kg for males with a body mass index (BMI) between 19and 26 kg/m2 inclusive, BMI = weight (kg)/height2 (m2)
• 4 The subject is able to communicate well with the investigator, voluntary and able tounderstand and follow protocol procedures to complete the study;
• 5 The subject agrees not to have a childbearing plan from the date of signing theinformed consent form to 6 months after the last dose, and must use effective non-drugcontraception with a partner of childbearing potential;
• 6 Normal physical examination, vital signs or abnormal physical examination, vitalsigns without clinical significance

Exclusion Criteria:

• 1 Females who are pregnant, lactating or have unprotected sex within two weeks priorto screening;
• 2 Past medical history or current cardiac, endocrine, metabolic, renal, hepatic,gastrointestinal, skin, infection, hematological, neurological or psychiatricdiseases/abnormalities, or related chronic diseases, or acute diseases, and theinvestigator evaluated that the subject was not suitable for the trial;
• 3 People who have abnormal and clinically significant results in vital signs, physicalexamination, laboratory tests, eye examination, 12-lead ECG and X-ray during screeningperiod;
• 4 Subjects Positive for Any of Hepatitis B Virus Surface Antigen (HBsAg), Hepatitis CVirus Antibody (Anti-HCV), Human Immunodeficiency Virus Antibody (Anti-HIV), andTreponema Pallidum Antibody (Anti-TP);
• 5 Clinically significant respiratory infection requiring antibiotic or antiviraltherapy within 7 days prior to randomization;
• 6 People who received surgical operation within 4 weeks prior to screening, or plannedto receive surgical operation during the study period;
• 7 People who participated in other clinical trials and took the study drug within 3months before screening;
• 8 Received immunoglobulins or blood products within 30 days prior to randomization;
• 9 Blood loss or blood donation of more than 400 mL within 2 months prior torandomization;
• 10 People who have potential difficulty in blood collection, or have a history of haloneedles or blood sickness;
• 11 A history of allergic reactions to another therapeutic monoclonal antibody orbiologic agent therapy, or any clear history of drug or food allergies, particularlythose with allergies to similar components to the drug in this trial;
• 12 People who have received or are planning to receive live-reduced or active vaccinesduring the 30 days prior to randomization and the entire study period (including thefollow-up period);
• 13 Smoking more than 5 cigarettes per day or using equivalent amounts of nicotine ornicotine-containing products during the 6 months prior to randomization and the entirestudy period (including the follow-up period);
• 14 People who had long-standing alcohol abuse or alcohol consumption of more than 14units (1 unit = 360 mL of beer or 45 mL of 40% alcohol or 150 mL of wine) of alcoholper week during the 3 months prior to screening and the entire study period (includingthe follow-up period), or those who tested positive for alcohol breath;
• 15 People with a history of substance abuse or positive urine drug screening;
• 16 Received any marketed or research biologics within 4 months or 5 half-lives (whichever is longer) prior to randomization;
• 17 Taking any prescription, over-the-counter and herbal medicines within 4 weeks priorto randomization, with the exception of vitamin products;
• 18 Use of any systemic cytotoxicity or systemic immunosuppressants within 6 monthsprior to randomization or during the study period, or any local cytotoxin or localimmunosuppressive drug within 30 days or 5 half-life periods (whichever is longer)prior to randomization or during the study period;
• 19 Parasitic infection is associated and is excluded if any of the following are met:
• During the screening period, the stool routinely checks positive for eggs;
• History of parasitic infection within 6 months prior to the screening period;
• Have traveled or planned to travel to endemic parasitic infection areas (including but not limited to Southeast and South-West Asia, South America andAfrica) within 6 months prior to screening visits;
• 20 Any situation in which the investigator believes that this poses a safety risk tothe subject in the trial or may interfere with the conduct of the study, or that theinvestigator believes that the subject may not be able to complete the study or maynot be able to comply with the requirements of the study.