Objectives:

Primary Objectives

• To investigate the safety and tolerability of single ascending doses of AZP- 531 in healthy volunteers.
• To investigate the safety and tolerability of single and multiple ascending doses of AZP-531 in overweight/obese volunteers.
• To investigate the safety and tolerability of single and multiple ascending doses of AZP-531 in patients with type 2 diabetes mellitus.

Secondary Objectives • To determine the plasma pharmacokinetic (PK) profile of AZP-531 after single and multiple doses.

Exploratory Objectives

• To obtain exploratory data on the effects of AZP-531 on the pharmacodynamic (PD) markers of blood glucose, interstitial glucose, insulin, and plasma acylated ghrelin (AG) and unacylated ghrelin (UAG)

Inclusion Criteria:

• Part A: Healthy male volunteers, aged 18 to 50 years (inclusive) with a body mass index (BMI) of 20 to 28 kg/m2 (inclusive).
• Part B: Female (of non-childbearing potential) and male overweight/obese volunteers, aged 18 to 65 years (inclusive) with a BMI of 28 to 38 kg/m2 (inclusive).
• Part C: Female (of non-childbearing potential) and male patients with a confirmed diagnosis of type 2 diabetes mellitus for at least 3 months

Exclusion Criteria:

• Part A: Females and male volunteers who smoke and/or use other nicotine products within 6 months of screening are excluded.
• Part B: Current or ex-smokers with a smoking history of greater than 10 pack years (1 pack year = 20 cigarettes smoked per day for 1 year) and any clinically significant abnormalities in physical examination, electrocardiogram (ECG), clinical chemistry, haematology, coagulation or urinalysis results at screening or on admission, as judged by the Investigator.
• Part C: Current or ex-smokers with a smoking history of greater than 10 pack years (1 pack year = 20 cigarettes smoked per day for 1 year), any clinically significant abnormalities other than those attributed to type 2 diabetes mellitus in physical examination, ECG, clinical chemistry, haematology, coagulation or urinalysis results at screening or on admission, as judged by the Investigator, and estimated glomerular filtration rate <40 mL*min-1*1.73m-2 calculated by the Modification of Diet in Renal Disease formula.