Can insulin glargine 300 reduce hypoglycemia risk?

This study compared patients with type 2 diabetes (T2D) switching to either insulin glargine 300 (Toujeo) or insulin glargine 100 (Lantus). It found that both types of insulin glargine improved blood glucose control, and insulin glargine 300 had a lower risk of hypoglycemia (dangerously low blood glucose levels) outside of a clinical trial.

T2D is a disorder in which the body does not respond well to the hormone insulin, which is responsible for removing glucose (sugar) from the blood. While some patients can manage T2D through lifestyle or oral medications, many patients eventually require injections of synthetic insulin.

Basal insulins are designed to last a long time in the body, leading to good blood sugar stability. Insulin glargine is an effective form of basal insulin that can last 24 hours. Insulin glargine 100 (glar-100) and insulin glargine 300 (glar-300) have the same chemical structure. However, the glar-300 solution is three times as concentrated. When it is injected into the muscle, glar-300 absorbs more slowly than glar-100. This makes the amount of insulin glargine in the body very stable. Controlled trials have found that patients taking glar-300 are less likely to experience hypoglycemia. However, trials can be different from standard treatment as they usually recruit only very healthy patients except for the T2D. It is not clear whether glar-300 reduces hypoglycemia for patients in regular office care.

This study included records from patients treated for T2D in the European Union. 1108 patients switched from a different insulin to insulin glargine. 1430 patients who had not previously received insulin started with insulin glargine. 

679 patients switched from a different insulin to glar-300, and 429 switched from a different insulin to glar-100. The most common previous insulin types were glar-100 (for those switching to glar-300) and insulin detemir (Levemir). Patients switching to glar-300 were more likely to have previous hypoglycemia and obesity. Researchers adjusted their results to account for these differences.

The two types of insulin glargine led to a similar improvement in glycated hemoglobin (HbA1c), which is a measure of blood glucose control over 2-3 months. Additionally, patients switching to glar-300 had a significantly greater improvement in hypoglycemia risk (1.29 vs 0.81 fewer events over 6 months).

For patients starting insulin for the first time, glar-100 led to significantly more improvement in HbA1c than glar-300 did (1.35% vs. 1.21% reduction). However, patients taking glar-300 had fewer hypoglycemic events (0.20 fewer), whereas those taking glar-100 had a small increase in hypoglycemia (0.04 more events over 6 months).

This study found that glar-300 led to a lower risk of hypoglycemia than glar-100 in real-world patients. Both types of insulin glargine reduced blood sugar compared to other types of insulin.

This study was funded by Sanofi, the manufacturer of both Lantus and Toujeo. While the patent for Lantus has expired in the European Union, Toujeo is still under patent.