Pharmacokinetic Characteristics, Safety, and Immunogenicity of HLX319 Compared With EU-Phesgo®

Inclusion Criteria: 1. Male subjects aged ≥18 and ≤45 years; 2. The skin at the injection site is intact, without damage, tattoos, or other markings; 3. Subjects have no history of disease or past medical history abnormalities that, in the judgment of the study physician, would affect the trial; 4. Physical examination, vital signs, chest x-ray, electrocardiogram, and laboratory investigations are normal or show abnormalities without clinical significance. 5. Body weight (BW) ≥50 and ≤75 kg; 6. Body mass index (BMI) ≥19 and ≤24 kg/m² \[BMI = weight (kg) / height² (m²)\]; 7. Within 14 days prior to random allocation, left ventricular ejection fraction (LVEF) assessed by echocardiography is within the normal range (≥55%); Exclusion Criteria: 1. Clinically significant diseases including but not limited to the gastrointestinal tract, kidneys, liver, nerves, blood, endocrine system, tumors, respiratory system, immune system, mental health, and cardiovascular and cerebrovascular diseases; 2. History of allergy or hypersensitivity reactions. 3. Intake of prescription drugs, over-the-counter drugs, or traditional Chinese medicine within 28 days prior to randomization; 4. History of blood donation or blood loss (\>450mL) within 3 months prior to randomization; 5. Positive test results for Hepatitis B Surface Antigen (HbsAg), Hepatitis C Virus (HCV) antibodies, and Human Immunodeficiency Virus (HIV) antibodies, or abnormal and clinically significant quantitative test results for syphilis spirochetes as determined by the sub investigator; 6. History of upper respiratory tract infection or other acute infections within 2 weeks prior to r randomization; 7. History of drug abuse, substance use; 8. History of alcoholism or positive alcohol test results; 11\. History of long-term heavy smoking .