Inclusion Criteria:

• * Diagnosis of type 1 diabetes mellitus for at least 1 year.
• * Participants 18 to 70 years of age.
• * Current use of an insulin pump for at least 3 months with stable insulin pump settings for \>2 weeks OR current use of multiple day injection insulin therapy with stable doses for \>2 weeks.
• * Uses a carbohydrate ratio, at lease occasionally, to dose meal time insulin.
• * HbA1c ≤ 10.5% at screening.
• * Total daily insulin requirement is less than 139 units/day.
• * Willingness to follow all study procedures, including attending all clinic visits.
• * Willingness to sign informed consent and HIPAA documents.

Exclusion Criteria:

• * Individual of childbearing potential who is pregnant or intending to become pregnant or breast-feeding, or is not using adequate contraceptive methods. Acceptable contraception includes birth control pill / patch / vaginal ring, Depo-Provera, Norplant, an IUD, the double barrier method (the woman uses a diaphragm and spermicide and the man uses a condom), or abstinence.
• * Any cardiovascular disease, defined as a clinically significant EKG abnormality at the time of screening or any history of: stroke, heart failure, myocardial infarction, angina pectoris, or coronary arterial bypass graft or angioplasty. Diagnosis of 2nd or 3rd degree heart block or any non-physiological arrhythmia judged by the investigator to be exclusionary.
• * Renal insufficiency (GFR \< 60 ml/min, using the MDRD equation as reported by the OHSU laboratory).
• * Liver failure, cirrhosis, or any other liver disease that compromises liver function as determined by the investigator.
• * History of severe hypoglycemia during the past 3 months prior to screening visit or hypoglycemia unawareness as judged by the investigator. Participants will complete a hypoglycemia awareness questionnaire. Participants will be excluded for four or more R responses.
• * History of diabetes ketoacidosis during the prior 3 months prior to screening visit, as diagnosed on hospital admission or as judged by the investigator.
• * Adrenal insufficiency.
• * Any active infection requiring treatment (example soft tissue infection requiring antibiotics).
• * Known or suspected abuse of alcohol, narcotics, or illicit drugs.
• * Seizure disorder.
• * Active foot ulceration.
• * Major surgical operation within 30 days prior to screening.
• * Use of an investigational drug within 30 days prior to screening.
• * Chronic usage of any immunosuppressive medication (such as cyclosporine, azathioprine, sirolimus, or tacrolimus).
• * Bleeding disorder, treatment with warfarin, or platelet count below 50,000.
• * Allergy to aspart insulin.
• * Allergy to pramlintide.
• * Current administration of oral or parenteral corticosteroids.
• * Any life-threatening disease, including malignant neoplasms and medical history of malignant neoplasms within the past 5 years prior to screening (except basal and squamous cell skin cancer).
• * Current use of any medication intended to lower glucose other than insulin or pramlintide (ex. use of liraglutide, metformin).
• * Gastroparesis
• * Diets consisting of less than 50 grams of carbohydrates per day.
• * Dietary restrictions or allergies to the study meals
• * Any clinically significant disease or disorder which in the opinion of the Investigator may jeopardize the participant's safety or compliance with the protocol.