This is a multicenter, randomized, double-blind, placebo-controlled phase III clinical study in adult obese/overweight subjects in China to evaluate the efficacy and safety of GZR18 Injection in the subjects.

Inclusion Criteria:

• Age ≥ 18 years (as of the date of signing the Informed Consent Form (ICF)), male or female.
• Obese (BMI ≥ 28 kg/m2) or overweight (24 kg/m2 ≤ BMI < 28 kg/m2) with at least one comorbidity.
• Able to understand the procedures and methods in this study; willing and able to maintain a stable diet and exercise lifestyle during the research period, and willing to sign the ICF voluntarily.
• Subjects of childbearing potential with no birth plan from the signing of ICF to 8 weeks after the last dose, willingness to take effective contraceptive measures, and no plan for sperm donation. Females of childbearing potential must not be lactating and must have negative results of pregnancy tests at screening and Visit 2 (before randomization).

Exclusion Criteria:

• Known or suspected hypersensitivity to glucagon like peptide-1 receptor agonist (GLP-1RA) drugs or excipients.
• History of drug abuse prior to screening.
• History of alcohol abuse within 6 months before screening.
• Weight change of > 5.0% within 3 months before screening (self-report).
• Presence of limb deformity or mutilation affecting height measurement.