This is a pilot study to examine and compare the efficacy of supervised injections of long acting insulins degludec and glargine to protect youth with poorly controlled type 1 diabetes (T1D) from development of ketones.

This study will compare the proportion of days with fasting β-hydroxybutyrate levels ≥0.6 mmol/L at the start of the school week following weekend/holiday breaks in subjects who have been randomized to receive daily injections of I-deg or I-glar. Hypothesis: β-hydroxybutyrate levels will be lower in the morning of the first day of the school week in subjects receiving I-deg than in subjects receiving I-glar, since the long half-life of I-deg will compensate for missed insulin doses over the weekend/holidays. To remove variability due to potential non-compliance during the school week, this study will utilize our routine clinical practice of supervised insulin administration and monitoring of blood glucose and ketones during the school day.

Inclusion Criteria:

• Clinical diagnosis of T1D, diagnosed at least 12 months prior to enrollment
• HbA1c ≥8.5%9 and <14% on enrollment
• Taking no medications known to affect blood glucose levels other than insulin.
• Ability to provide participant written informed consent if age 18 years, or parental written informed consent and participant assent if participant is < age 18 before any trial-related activities
• Current regimen includes insulin detemir or I-glar, as long acting insulin
• Willingness to use either I-glar or I-deg pens as basal insulin, and have school personnel supervise administration
• Willingness to have school personnel supervise fasting blood β-hydroxybutyrate levels first thing in the morning at the beginning and end of each school week
• Willingness to have school personnel supervise fasting blood glucose checks daily in the morning on school days, and eat breakfast after the fasting check

Exclusion Criteria:

• Female participants who are pregnant, breast-feeding or planning on becoming pregnant
• Participant (and parent if age <18) unable to read, write, and speak English.
• Adolescents who are home schooled or no longer attending secondary school
• Participant's school is unable to provide personnel to supervise injections of long-acting insulin or measurement blood glucose and β-hydroxybutyrate levels
• Known or suspected allergy to trial medication(s), excipients, or related products.
• Contraindications to study medications, including hypersensitivity to I-deg or one of its excipients, hypersensitivity to I-glar or one of its excipients, and administration of either during episodes of hypoglycaemia