Primary objective:

To compare metabolic control as measured by Blood Glucose (BG) upon arising from bed (7:00 am - 12:00 pm) in type 1 Diabetes mellitus patients who skip the morning meal during treatment with MDI basal/bolus insulin: Difference of change of blood glucose between 7:00 am and 11:00 am between patients on Insulin glargine and NPH insulin.

Secondary objective:

To perform an evaluation between the two patient groups for BG (10:00 pm and 12:00 pm) as well as for serum insulin, free fatty acid levels and β-hydroxybutyrate (7:00 am - 12:00 pm).

Inclusion Criteria:

Patients with type 1 Diabetes mellitus who have been treated with MDI (Multiple Daily Injection) basal/bolus insulin, regular insulin/short acting insulin analogue + NPH insulin on a stable dose (no change more than 10 %) for at least 4 weeks prior to study entry, who have an HBA1c smaller/equal 9 % (measured at visit 1) and a BMI smaller/equal 35 kg/m2. In addition, patients must have a FBG value at day 1 before skipping meal (6:00 am - 07:00 am) between 90 - 120 mg/dl (5.0 - 6.5 mmol/l).

Exclusion Criteria:

• Breast-feeding
• History of hypersensitivity to the study medication or to drugs with similar chemical structures
• Likelihood of requiring treatment during the study period with drugs not permitted by the study protocol
• Treatment with any investigational drug in the last 30 days before study entry
• Clinically relevant cardiovascular, hepatic, neurological, endocrine, or other major systemic disease making implementation of the protocol or interpretation of the study results difficult
• History of drug or alcohol abuse

No subjects who have previously been treated with Insulin glargine will be enrolled in this study.