This is a sequential efficacy and safety study in pediatric patients with type 1 diabetes. Subjects will be administered insulin to induce a low normal glycemic state and will then receive an age-appropriate dose of G-Pen (glucagon injection) in a clinical research center (CRC) or comparable setting.

This is an open-label, Phase 3 sequential efficacy and safety study in pediatric patients ages 2-17 with type 1 diabetes. Patients will complete the screening procedures up to 30 days before dosing to determine eligibility before enrollment to the treatment phase.

The procedure to evaluate the efficacy of G-Pen (glucagon injection) consists of inducing a low normal glycemic state by administration of insulin. Subjects ages 2-11 will then be given a 0.5 mg dose of G-Pen, while subjects ages 12-17 will receive a 1 mg dose of G-Pen. Subjects ages 12-17 will return for a second visit 1-4 weeks later and will receive a 0.5 mg dose of G-Pen when in a low normal glycemic stare. Plasma glucose and glucagon levels will be monitored for 90 and 180 minutes post-dosing, respectively, at all visits.

A follow-up phone call as a safety check will be conducted 3 - 14 days following administration of the final dose.

Inclusion Criteria:

• diagnosed with T1D for at least 6 months at Screening.
• current usage of daily insulin treatment.

Exclusion Criteria:

• pregnant or nursing
• renal insufficiency
• hepatic synthetic insufficiency
• aspartate or alanine aminotransferase > 3 times the upper limit of normal
• hematocrit less than or equal to 30%
• use of > 2.0 U/kg total insulin dose per day
• inadequate venous access
• current seizure disorder
• history of pheochromocytoma or disorder with increased risk of pheochromocytoma
• history of insulinoma
• history of glycogen storage disease.
• active use of alcohol or drugs of abuse
• administration of glucagon within 14 days of the first treatment visit
• participation in other studies involving an investigational drug or device within 30 days

Adverse events were collected from the signing of informed consent through the follow-up phone call, which was completed 3-14 days after the last dose of treatment. The maximum adverse event (AE) collection period was 44 days for subjects receiving a single dose, and 72 days for subjects receiving 2 doses of G-Pen.