A Randomized, Double-Blind, Placebo-Controlled, Single-Dose Escalation Phase I Clinical Study to Assess the Safety, Pharmacokinetics, and Immunogenicity of HLX6018 in Healthy Subjects

Inclusion Criteria:

1. Fully informed about the nature, significance, potential inconveniences, andassociated risks of the study prior to enrollment. Comprehend the study's proceduresand methodology, agree to follow the clinical study protocol, and give voluntarywritten informed consent;

2. 18-55 years old, including the boundary value, male or female;

3. Body weight: 45-85 kg for females and 50-85 kg for males, including the boundaryvalue; body mass index (BMI): 18.0-28.0 kg/m2 , including the boundary value, (BMI =body weight (kg)/body height2 (m2));

4. Subjects, including males, must have no childbearing plan and take effectivecontraceptive measures from the time of informed consent to 6 months after theadministration of the study drug.

5. Physical examinations and vital signs should be normal or abnormal without clinicalsignificance.

Exclusion Criteria:

1. Any clinically significant laboratory test abnormalities or, within 12 months beforescreening, any other clinically significant clinical findings indicative ofdiseases, including but not limited to gastrointestinal, renal, hepatic,neurological, hematological, endocrine, oncological, pulmonary, immunological,psychiatric, or cardiovascular conditions;

2. Donation/loss of ≥ 450 mL of blood or receipt of blood transfusion or use of bloodproducts within 3 months prior to screening, or planning to donate blood during thestudy or within 1 month after the end of the study;

3. Patients with severe trauma or major surgery within 3 months before screening, orplanning to undergo surgery during the study;

4. Patients who smoke more than 5 cigarettes per day in the 3 months before screening;

5. History of drug abuse or addiction or alcohol abuse (14 units of alcohol per week: 1unit = 285 mL of beer, or 25 mL of spirits, or 100 mL of wine);