The Minimed®640G system (MM640G) consists of a combination of insulin and glucose sensor for continuous glucose monitoring (CGM). Here, the glucose sensor transmits not only the continuous glucose data on the display of insulin pump but, in the case of hypoglycemia also interrupt their insulin delivery of pump. In the currently available system Paradigm®VEO, the interruption takes place at a settled threshold level. In difference in the new system MM640G the shutdown algorithm can already be proactive and help avoid hypoglycemia completely. The so called PLGM algorithm (predictive low glucose management) should be tested in the user evaluation. The main objective is to answer the question of reducing the rate of hypoglycemia by application of the new PLGM algorithm.

Included are a total of 24 patients, aged 1-21 years, in three pediatric diabetes centers.

In the first phase of two weeks, the sensor-augmented pump therapy (SaP) is carried out without these interruption PLGM algorithm. In a second phase for 6 weeks, the PLGM function is set. Both phases are compared in terms of the rate of hypoglycemia, the time spent and the area under the curve (AUC) glucose range (values <70 mg / dl (3.9 mmol / l)).

Inclusion Criteria:

• type 1 diabetes, diagnosed since 12 month at least
• continuous subcutaneous insulin infusion (CSII) since 3 month at least
• stable outcome since 3 month at least
• willingness of patients/ parents to wear a glucose sensor for 2 month
• willingness of patients/ parents to use the Minimed®640G system
• willingness of patients/ parents to complete a diary
• willingness of patients/ parents to comply the requirements of the study protocol

Exclusion Criteria:

• longer absence of the patients (not able to attend the study visits)
• subject with allergy of sensor or specific sensor components
• communication problems
• significant history of eating disorder, anorexia, bulimia
• pregnancy
• significant history of drug abuse or/ and alcoholism
• patient do not want to attend the trial
• missing informed consent

• patients with type 1 diabetes
• CSII since 3 month at least