Is Tresiba (insulin degludec) the same as Glargine (insulin glargine)?

Tresiba (insulin degludec) vs. Glargine (insulin glargine): Differences and Similarities

No, Tresiba (insulin degludec) is not the same as insulin glargine. They are different long-acting insulin analogs with distinct pharmacokinetic profiles, although both are used as basal insulins for diabetes management.

Key Differences Between Insulin Degludec and Insulin Glargine

Molecular Structure and Duration of Action

• Insulin degludec (Tresiba) is an ultra-long-acting insulin analog with:

  • Duration of action >42 hours 1
  • Half-life of 17-21 hours (approximately double that of glargine) 2
  • Forms a depot in subcutaneous tissue with continuous, slow release of monomers 2

• Insulin glargine has:

  • Duration of action up to 24 hours 3
  • Different molecular structure and mechanism of action

Pharmacokinetic Profile

• Insulin degludec provides:
  • More stable glucose-lowering effect
  • Less day-to-day variability compared to insulin glargine 1
  • Flat and predictable action profile

Clinical Considerations

Hypoglycemia Risk

• The DEVOTE trial demonstrated that insulin degludec had:
  • Lower incidence of severe hypoglycemia compared to insulin glargine U-100 (4.9% vs 6.6% of patients)
  • Estimated rate ratio of 0.60 [0.48; 0.76] for severe hypoglycemic events 4

Dosing Flexibility

• Insulin degludec offers greater flexibility in dosing time:
  • Can be administered at different times of day when needed
  • Allows for varying intervals (8-40 hours) between doses 5
  • Maintains glycemic control despite flexible administration 6

Formulations

• Insulin degludec is available in:

  • 100 units/mL (U-100)
  • 200 units/mL (U-200) formulation for patients requiring larger insulin doses 1

• Insulin glargine is available in:

  • U-100 formulation (standard)
  • U-300 formulation (Toujeo)

Compatibility with Other Insulins

• Insulin degludec can be mixed with rapid-acting insulin (available as degludec/aspart coformulation) 2
• Insulin glargine should not be mixed with other insulins 3

Clinical Practice Considerations

When to Consider Each Insulin

• Consider insulin degludec for:

  • Patients with frequent severe hypoglycemia, especially nocturnal hypoglycemia 4
  • Patients needing flexible dosing schedules 6
  • Patients requiring large volumes of basal insulin (U-200 formulation) 1

• Consider insulin glargine for:

  • Standard basal insulin coverage with once-daily dosing
  • Patients with established stable regimens on glargine

Cautions and Monitoring

• When switching between insulin types:

  • Monitor blood glucose levels closely during transition period 3
  • Consider dose reduction of 10-20% when switching from degludec to glargine U-300 for patients at high risk for hypoglycemia 3

• Safety considerations for insulin degludec:

  • Some studies have raised questions about potential cardiovascular risk compared to glargine 5
  • The FDA required additional cardiovascular outcomes data before approval in the US

Guidelines Perspective

• The World Health Organization recommends:
  • Human insulin as first-line for managing blood glucose in adults with type 1 and type 2 diabetes (strong recommendation) 7
  • Long-acting insulin analogs (like degludec or glargine) should be considered for adults with frequent severe hypoglycemia with human insulin (weak recommendation) 7

Conclusion

While both insulin degludec and insulin glargine are long-acting basal insulins used for similar clinical indications, they have distinct pharmacokinetic profiles, with degludec offering a longer duration of action, less variability, and potentially lower risk of nocturnal hypoglycemia. The choice between these insulins should consider the patient's specific needs regarding hypoglycemia risk, dosing flexibility, and cost considerations.