A randomized, open-label, parallel, single-dose, single-center, phase I clinical study evaluating the pharmacokinetic characteristics, safety and immunogenicity of subcutaneous injection and intravenous infusion of QX008N injection in healthy subjects

INTERVENTION: Group 1:Subcutaneous injection QX008N 280mg;Group 2:Subcutaneous injection QX008N 560mg;Group 3:Intravenous injection QX008N 560mg; CONDITION: Adults with Severe, poorly controlled asthma PRIMARY OUTCOME: Pharmacokinetics; SECONDARY OUTCOME: Safety;Immunogenicity; INCLUSION CRITERIA: Subjects who meet all the following inclusion criteria can be included: 1.Healthy adults aged 18 to 50 (inclusive) when signing the ICFs. 2.Male subjects weigh at least 50.0 kg and no more than100.0 kg (inclusive), and female subjects weigh at least 45.0 kg and no more than 100.0 kg (inclusive). Have a body mass inde X(BMI = weight/height square (kg/m2)) between 18.0‐28.0 kg/m2 (inclusive). 3.Subjects whose results are normal or abnormal but not clinically significant after a thorough examination including vital signs, physical examination, laboratory tests, 12‐lead electrocardiogram, abdominal ultrasound and orthopantomogram. 4.Subjects who agree to have no childbearing plans and voluntarily use effective contraception during the trial and for 6 months after the trial ends. 5.Subjects fully understand the study objective, nature, methods and possible adverse reactions, voluntarily become subjects, and sign the ICFs. 6.Subjects can complete t