This trial is conducted in Europe. The aim of this trial is to establish the dose response relationship on glycaemic control of five dose levels of NNC90-1170.

Inclusion Criteria:

• Subjects with type 2 diabetes
• Duration of diabetes at least 3 months
• Both diet treated and patients in therapy with OHA (oral hypoglycemic agents)
• Body Mass Index maximum 40 kg/m^2
• HbA1c based on analysis from central laboratory: Between 7.5-10.0%, both inclusive, for diet treated, or maximum 9.0% for OHA treated

Exclusion Criteria:

• Liver or renal disease
• Cardiac problems
• Uncontrolled treated/untreated hypertension
• Proliferative retinopathy
• Recurrent severe hypoglycaemia as judged by the Investigator
• Known or suspected allergy to trial product or related products
• Use of any drug (except for OHAs) which in the Investigator's opinion could interfere with the blood glucose level