The purpose of this study is to investigate the safety and tolerability of AZD5658 following ascending single oral doses in Type 2 Diabetics. It will also estimate the maximum tolerated dose.

This is a randomized, single-blind, placebo-controlled, single-center, phase 1 study to assess the safety, tolerability, pharmacokinetics, pharmacodynamics and the effect of fasting after single ascending oral doses of AZD5658 in type 2 diabetes mellitus patients.

Inclusion Criteria:

• Patients must be of non-childbearing potential.
• Body mass index between greater than or equal to 19 and less than or equal to 40 kg/m2
• Patients with confirmed Type 2 Diabetes diagnosis for at least 1 year and treated with Metformin

Exclusion Criteria:

• Clinically significant illness or clinically relevant trauma within 2 weeks before the first administration of the IP
• Participation in another clinical study during the last 30 days prior to enrollment
• Significant cardiovascular event within the last 6 months prior to enrollment