Demonstrate that usage of RT-CGM (Real time continuous glucose monitoring) reduces the frequency of low CGM-recorded glucose events in patients using MDI (Multiple daily injections) that are at risk for hypoglycemic events.

In a randomized controlled trial the primary hypothesis is tested if the usage of RT-CGM in the intervention group (CGM group) reduces the frequency of glucose values <55 mg/dl in patients with hypoglycemia problems (hypoglycemia unawareness or documented previous severe hypoglycemia) significantly more than in the control group receiving usual care (without CGM).

Secondary is tested if patients in the CGM group showed a significantly more favorable change in the below defined secondary endpoint than patients in the control group after 26 weeks follow up.

Inclusion Criteria:

• Patients with type 1 diabetes for at least 12 months on multiple daily injections (MDI). MDI is defined as prandial insulin injections at each major meal (excludes pre-mixed insulin) with doses determined by SMBG and carbohydrate counting, and basal insulin injection(s)
• Age ≥ 18 years
• HbA1c ≤ 9.0 % performed within 4 months before begin of the study
• High risk for severe hypoglycemia (defined as a score of 4 or higher on the Hypoglycemia unawareness scale (HUS) or a history of at least one severe hypoglycemic event in the last 12 months (required third part assistance, not able to treat themselves))
• Willing to not use paracetamol or drugs containing it
• Signed and dated Informed Consent Form

Exclusion Criteria:

• Use of personal real-time-CGM 3 months prior to study entry and during the study (except study devices)
• Use of a flash-glucose monitoring system 3 months prior to study and during the study
• Alcoholism or drug abuse
• Unable to comply with the protocol at the investigators discretion, such as known psychiatric diagnosis, cognitive / physical decline
• Pregnancy or lactation period
• Severe known allergies, e.g. against plaster
• Mental incapacity or language barriers precluding adequate compliance with the study procedures
• Limited or no legal capacity or legal guardianship
• Dependency from the sponsor or the clinical investigator (e.g. co-workers of the sponsor or the clinical research center or their families)
• Participation in another study at the same time with a non-approved drug or a non-CE-labelled medical device.