Inclusion Criteria:

• Male or female of age 18 to 65 years, inclusive. Females of child-bearing potential must use a standard and effective means of birth control for the duration of the study.
• Patients with Type 1 diabetes mellitus treated with insulin for greater than or equal to 12 months.
• BMI 18.0 to 29.0 kg/m2, inclusive.
• HbA1c (glycosylated hemoglobin A1C) less than or equal to 10% based on local laboratory results.
• Fasting C-peptide less than 0.6 ng/mL.
• Current treatment with insulin less than 1.2 U/kg/day.
• Patients should be in good general health based on medical history and physical examination, without medical conditions that might prevent the completion of study drug injections and assessments required in this protocol.

Exclusion Criteria:

• Known or suspected allergy to any component of any of the study drugs in this trial.
• Previous enrollment in this trial.
• A patient who has proliferative retinopathy or maculopathy, and/or severe neuropathy, in particular autonomic neuropathy, as judged by the Investigator.
• Clinically significant (as judged by the Investigator) active disease of the gastrointestinal, cardiovascular (including a history of arrhythmia or conduction delays on ECG), hepatic, neurological, renal, genitourinary, or hematological systems, or uncontrolled hypertension (diastolic blood pressure greater than or equal to 100 mmHg and/or systolic blood pressure greater than or equal to 160 mmHg after 5 minutes in the supine position).
• History of any illness or disease that in the opinion of the Investigator might confound the results of the trial or pose additional risk in administering the study drugs to the patient.
• Clinically significant findings (as judged by the Investigator) in routine laboratory data, including anemia with hemoglobin less than lower limits of normal at screening.
• Use of drugs which may interfere with the interpretation of trial results or are known to cause clinically relevant interference with insulin action, glucose utilization, or recovery from hypoglycemia.
• Recurrent major hypoglycemia or hypoglycemic unawareness, as judged by the Investigator.
• Current addiction to alcohol or substances of abuse as determined by the Investigator.
• Blood donation (> 500 mL) within the previous 9 weeks prior to Visit 2A on study.
• Pregnancy, breast-feeding, the intention of becoming pregnant, or not using adequate contraceptive measures (adequate contraceptive measures consist of sterilization, intra-uterine device [IUD], oral or injectable contraceptives or barrier methods).
• Mental incapacity, unwillingness, or language barriers precluding adequate understanding or cooperation.
• Symptomatic gastroparesis.
• History or evidence of use of any tobacco- or nicotine-containing product within 6 months of screening or screening quantitative urine nicotine concentration >50 ng/mL.
• Receipt of any investigational drug within 4 weeks of Visit 2A in this study.
• Any condition (intrinsic or extrinsic) that in the judgment of the Investigator will interfere with trial participation or evaluation of data.
• Current use of insulin pump therapy.