The main purpose of this study is to investigate the efficacy and safety of XW003 versus placebo in patients with type 2 diabetes mellitus (T2DM) inadequately controlled by diet and exercise alone

In this Phase 3 study, eligible participants will be randomized in a 2:2:1:1 ratio to receive once-weekly subcutaneous XW003 (high or low dose) or volume matching placebo as an adjunct to lifestyle intervention for 24 weeks. The core treatment phase will be followed by a 28-week open-label period where all participants receive XW003.

Inclusion Criteria:

1. Ability and willingness to participate in the study, give written informed consent, and comply with the study specific requirements and all protocol procedures.
2. Sex: male or female; Age: 18 to 75 years, inclusive
3. BMI: 20.0 kg/m^2 to 35.0 kg/m^2, inclusive
4. Have been diagnosed with T2DMthat is inadequately controlled with at least 3 months of diet and exercise prior to screening.
5. HbA1c ranging from 7.5% to 11.0% at screening, inclusive
6. FPG ≤13.9 mmol/L at screening.

Exclusion Criteria:

1. History of type 1 or other types of diabetes mellitus.
2. Use of any GLP-1 analogue during the 3 months preceding to screening.
3. History of proliferative diabetic retinopathy, diabetic maculopathy, diabetic neuropathy, or diabetic foot during the 6 months preceding screening.
4. History of acute or chronic pancreatitis or high risk factors for pancreatitis.
5. Personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia syndrome type 2.
6. History of stomach surgeries or disorders associated with slowed emptying of the stomach during the past 6 months.
7. History of heart attack, stroke, or congestive heart failure of Grade 3 or 4 in the past 6 months.