Extension Study to Assess Safety and Efficacy of Mylan's Insulin Glargine and Lantus® in Type 1 Diabetes Mellitus (T1DM) Patients

1. Patients who have completed the 52-week treatment period (irrespective of their age at the completion of MYL-GAI-3001 trial) of the MYL-GAI-3001 trial and were assigned to Lantus® in that study.
2. Patients or their legal representatives must give written and signed informed consent before starting any protocol-specific procedures.
3. The patient is able and willing to comply with the requirements of the extension study protocol including the 8-point self-monitoring blood glucose, completion of patient diary records as instructed and following a recommended diet and exercise plan for the entire duration of the extension study.

4. Female patients complying with the following:

   • Female patients of childbearing potential must be using oral contraception or two other acceptable methods of contraception, (e.g., intra-uterine device plus condom, spermicidal gel plus condom, diaphragm plus condom, etc.) from the time of randomization throughout the entire study.
   • Periodic abstinence (e.g., calendar, ovulation, symptothermal, post-ovulation methods) and withdrawal are not acceptable methods of contraception.
   • Postmenopausal females must have had no menstrual bleeding for at least 1 year prior to inclusion in MYL-GAI-3001 study.
   • Female patients who report surgical sterilization must have had the procedure at least 6 months prior to inclusion to MYL-GAI-3001 study.
   • All female patients of childbearing potential, must have negative pregnancy test results at baseline (week 0) and at each clinic visit as per the SCHEDULE OF ACTIVITIES.
   • If female patients have male partners who have undergone vasectomy, the vasectomy must have occurred more than 6 months prior to inclusion in MYL-GAI-3001 study.

Exclusion Criteria:

1. History or presence of a medical condition or disease that in the Investigator's opinion would place the patient at an unacceptable risk from trial participation.
2. History of clinically significant (i.e., significant enough to alter the insulin dose requirement, as per the Investigator) acute bacterial, viral or fungal systemic infections in the 4 weeks prior to inclusion / randomization (recorded while collecting patient history) in to the MYL-1501D-3003 extension study
3. Patients scheduled to receive another investigational drug during the extension study period
4. Any major elective surgery requiring hospitalization planned during the extension study period.
5. Moderate insulin resistance, defined as requiring insulin (Basal + Prandial) of ≥1.5 U/kg/day (Lantus® in U/kg/day or Mylan's insulin glargine in IU/kg/day).