The purpose of this study is to assess the efficacy of the Low Glucose Suspend (LGS) feature in reducing hypoglycemia with the MiniMed Paradigm® X54 System with hypoglycemic induction from exercise.

The study will consist of a total of 50 subjects, age 16 through 60 years with Type 1 Diabetes Mellitus.

50 subjects with previously diagnosed Type 1 Diabetes Mellitus will be studied. The subject population includes the following subsets: 4 pediatric subjects aged 16 -17 years, 4 young adult subjects age 18-21 years, and 42 adult subjects age 22-60 years at time of enrollment. Results for all subjects will be analyzed.

Inclusion Criteria:

• Subject is between the ages of 16 - 60 years old
• A clinical diagnosis of Type 1 Diabetes Mellitus, as determined by the Investigator, for a minimum of 12 months duration
• Subject has been on a Medtronic insulin pump for at least 3 months, which includes but is not limited to those on sensor augmented insulin pump therapy
• Subject has an A1C value between ≥ 7.0% and ≤ 10.0% at time of enrollment; as measured during the screening visit
• Subject must have a documented stress treadmill test within the last three years of enrollment if the subject had diabetes for >20 years
• Subject willing to follow protocol and procedures for study.

Exclusion Criteria:

• Systolic blood pressure on screening visit is >140 Millimeters of Mercury
• Diastolic blood pressure on screening visit is >90 Millimeters of Mercury
• Subject has a history of hypoglycemic seizure or hypoglycemic coma within the last two years
• Subject unable to tolerate tape adhesive in the area of sensor placement;
• Subject has any active adverse skin condition in the area of sensor placement (i.e. psoriasis, rash, staphylococcus infection) that is not resolved at the time of enrollment
• Subject is pregnant or plans to become pregnant during the course of the study
• Subject has a history of myocardial infarction, unstable angina, coronary artery bypass surgery, coronary artery stenting, transient ischemic attack, cerebrovascular accident, angina, congestive heart failure, ventricular rhythm disturbances or thromboembolic disease
• Subject has active Graves disease
• Subject with renal impairment or creatinine above the normal reference range (of the laboratory that the clinical site is utilizing), as demonstrated by the screening laboratory value
• Subject is outside of the normal reference range (of the laboratory that the clinical site is utilizing) for hematocrit, as demonstrated by screening laboratory value
• Subject is outside of the normal reference range (of the laboratory that the clinical site is utilizing) for potassium, as demonstrated by screening laboratory value
• Subject is outside of the normal reference range (of the laboratory that the clinical site is utilizing) for Thyroid-Stimulating Hormone (TSH), as demonstrated by screening laboratory value
• Subject is outside of the normal reference range (of the laboratory that the clinical site is utilizing) for free Thyroxine (T4), as demonstrated by screening laboratory value
• Subject has history of smoking for >5 years
• Electrocardiogram findings observed during the screening visit, which are deemed by the investigator to represent active ischemia or a condition that would compromise subject safety
• The stress treadmill (if subject met inclusion criteria #7) results are deemed by the investigator to represent active ischemia or a condition that would compromise subject safety
• Subject is currently participating in an investigational study (drug or device)
• Subject is currently on beta blocker medication
• Subject has taken oral or injectable steroids within the last 30 days
• Subject is deemed by the Investigator to be unwilling or unable to follow the protocol
• Subject has a history of diagnosed medical eating disorder
• Subject has a history of known illicit drug abuse
• Subject has a history of known abuse with prescription medication
• Subject has a history of visual impairment which would not allow subject to participate in the study and perform all study procedures safely per investigator discretion
• Subject has a history of current alcohol abuse
• Any other condition including abnormalities found on the screening tests which in the opinion of the Investigator, may preclude him/her from participating in the study

Severe adverse event data and adverse event data were collected during the 35-46 days of study duration