Last reviewed 2026-04-22 · How we verify

Insulin glargine U100

Insulin glargine is a long-acting basal insulin that binds to insulin receptors on cells to promote glucose uptake and reduce blood glucose levels.

Insulin glargine is a long-acting basal insulin that binds to insulin receptors on cells to promote glucose uptake and reduce blood glucose levels. Used for Type 1 diabetes mellitus, Type 2 diabetes mellitus.

At a glance

Mechanism of action

Insulin glargine is a recombinant human insulin analog modified to have an extended duration of action (up to 24 hours). It binds to insulin receptors on muscle, fat, and liver cells, facilitating glucose transport into cells and promoting glycogen synthesis while inhibiting gluconeogenesis. The U100 formulation contains 100 units per milliliter and is designed to provide steady basal insulin coverage for patients with diabetes.

Approved indications

• Type 1 diabetes mellitus
• Type 2 diabetes mellitus

Common side effects

• Hypoglycemia
• Injection site reactions
• Weight gain
• Lipodystrophy

Key clinical trials

• A Research Study to See How a Weekly Insulin, Insulin Icodec, Helps in Reducing the Blood Sugar Compared to Daily Insulin Glargine, Both in Combination With Insulin Aspart, in Adults With Type 1 Diabetes (PHASE3)
• Efficacy and Safety of THDB0206 Compared to Insulin Lispro Injection in Participants With Type 2 Diabetes (PHASE3)
• Efficacy and Safety of THDB0206 Compared to Insulin Lispro Injection in Participants With Type 1 Diabetes (PHASE3)
• A Phase III Clinical Study to Assess the Efficacy and Safety of GZR4 in Insulin-naive Subjects With Type 2 Diabetes Mellitus (T2DM) (PHASE3)
• A Phase III Clinical Study to Assess the Efficacy and Safety of GZR4 in Type 2 Diabetes Mellitus Subjects (T2DM) Treated With Basal + Prandial Insulin (PHASE3)
• A Research Study to Look Into How Semaglutide, Together With a Lower Dose of Insulin Glargine, Compares to a Higher Dose of Insulin Glargine Alone in People With Type 2 Diabetes (SUSTAIN OPTIMIZE) (PHASE3)
• A Research Study to See How Switching From a Daily Basal Insulin to a New Weekly Insulin, Insulin Icodec, Helps in Reducing the Blood Sugar Compared to Daily Insulin Glargine in Adults With Type 2 Diabetes (PHASE3)
• A Study of Insulin Efsitora Alfa (LY3209590) as a Weekly Basal Insulin Compared to Insulin Glargine in Adult Participants With Type 2 Diabetes on Multiple Daily Injections (PHASE3)

Primary sources

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