A Study of HDM1005 in Participants With T2DM Not Controlled With Metformin Alone or in Combination With a Sodium-Glucose Cotransporter 2 (SGLT2) Inhibitor

• HDM1005 1 (Drug): administered SC, QW, 52 week
• HDM1005 2 (Drug): administered SC, QW, 52 week
• Mazdutide (Drug): administered SC, QW, 52 week

Primary outcomes

• Change from baseline in Hemoglobin A1c (HbA1c) [Baseline, Week 40]: HbA1c is the glycosylated fraction of hemoglobin A. HbA1c is measured primarily to identify average plasma glucose concentration over prolonged periods of time.

Secondary outcomes

• Change from baseline in HbA1c [Baseline, Week 52]: HbA1c is the glycosylated fraction of hemoglobin A. HbA1c is measured to identify average plasma glucose concentration over prolonged periods of time
• The percentage of patients reaching the HbA1c targets of <7.0%, ≤6.5%, and <5.7% [Week 40, Week 52]: HbA1c is the glycosylated fraction of hemoglobin A. HbA1c is measured to identify average plasma glucose concentration over prolonged periods of time
• Change from baseline in fasting plasma glucose (FPG) [Baseline, Week 40, Week 52]: FPG is a test to determine sugar levels in serum sample after an overnight fast
• Change from baseline in body weight [Baseline, Week 40, Week 52]: Change from baseline in body weight is calculated by subtracting the baseline weight measurement from the post-treatment weight measurement at a specified time point

Sex: All, ages: 18 Years to 75 Years

Inclusion Criteria:

1. Confirmed as Type 2 Diabetes Mellitus (T2DM) for at least 12 weeks and on a stable dosage of metformin alone or in combination with an SGLT2 inhibitor for at least 12 weeks prior to screening.
2. Hemoglobin A1c (HbA1c) ≥7.5% and ≤11.0% (local laboratory) at screening; and ≥7.0% and ≤11.0% (central laboratory) at randomization.
3. Body Mass Index (BMI) ≥22.5 kg/m2.

Exclusion Criteria:

1. Other types of diabetes besides T2DM.
2. Acute complications of diabetes (such as diabetic ketoacidosis, diabetic lactic acidosis, or hyperosmolar non-ketotic coma) occurred within 24 weeks prior to signing the Informed Consent Form (ICF).
3. History of a level 3 hypoglycemic episode or a history of asymptomatic hyp oglycemic episodes within 24 weeks prior to signing the ICF.
4. History or family history of medullary thyroid carcinoma (MTC), thyroid C-cell hyperplasia, or multiple endocrine neoplasia type 2 (MEN2).
5. History of acute or chronic pancreatitis; or presence of risk factors for pancreatitis; or history of symptomatic gallbladder disease requiring treatment per investigator's assessment within 24 weeks prior to signing the ICF.
6. Investigator determines that the subject has a condition or disease affecting gastric emptying or gastrointestinal nutrient absorption, such as weight-loss surgery or other gastric resections, irritable bowel syndrome, dyspepsia, or gastroparesis.
7. Use of antidiabetic medications within 12 weeks prior to signing the ICF, with the exception of metformin monotherapy or combination therapy with an SGLT2 inhibitor; excluding short-term insulin use (cumulative duration ≤7 days) for concomitant illness, stress, or perioperative periods.
8. Hemoglobin (Hb) <100 g/L (female) or <110 g/L (male).
9. FPG ≥13.9 mmol/L.
10. Aspartate aminotransferase (AST) >3× upper limit of normal (ULN) and/or alanine aminotransferase (ALT) >3× ULN.
11. Total bilirubin >1.5× ULN.
12. Fasting triglyceride (TG) >5.6 mmol/L (500 mg/dL).

• Linong Ji, Study director, Peking University People's Hospital