Can Basaglar 30 Units Be Interchanged with Lantus?
Yes, Basaglar (insulin glargine) 30 units can be directly interchanged with Lantus (insulin glargine) 30 units on a unit-per-unit basis without dose adjustment. Both are insulin glargine formulations with equivalent pharmacokinetic profiles and clinical efficacy.
Evidence Supporting Direct Interchange
Regulatory and Clinical Equivalence
Basaglar is a follow-on biologic (biosimilar) to Lantus, developed after Lantus's patent expiration, and has been approved by the FDA as interchangeable with the originator product 1.
Real-world evidence demonstrates that patients converted from Lantus to Basaglar at the same dose showed no significant difference in mean basal insulin requirements at 3,6, or 12 months post-conversion (46.3 ± 32.7 U/d at baseline vs 45.9 ± 33.5 U/d at 6 months; P = 0.52) 1.
There were no significant differences in HbA1c changes at any time point when patients were switched from Lantus to Basaglar at equivalent doses 1.
Practical Switching Protocol
Direct 1:1 conversion: Switch 30 units of Lantus to 30 units of Basaglar without any dose adjustment 1.
Timing: Administer at the same time of day as the previous Lantus dose to maintain consistent basal insulin coverage 2.
Monitoring: Check fasting blood glucose daily for the first 1-2 weeks after switching to ensure glycemic stability, though significant changes are unlikely 1.
Important Clinical Considerations
Pharmacological Properties
Both Lantus and Basaglar have identical pharmacokinetic profiles with onset of action at approximately 1 hour, peakless activity, and duration of up to 24 hours 3, 4.
Neither formulation should be diluted or mixed with other insulins due to their low pH 2, 5.
Hypoglycemia Risk
The incidence of hypoglycemia is similarly low with both formulations, with no cases of severe hypoglycemia reported in switching studies 6.
If hypoglycemia occurs after switching, reduce the dose by 10-20% immediately 2.
Cost Considerations
- Basaglar has significantly lower estimated monthly acquisition costs compared to Lantus ($286 vs $341 at conversion, P < 0.001), making it a preferable option in value-based healthcare settings 1.
Common Pitfalls to Avoid
Do not reduce the dose prophylactically when switching from Lantus to Basaglar—use the same dose unless there is a specific clinical indication for adjustment 1.
Do not delay the switch due to concerns about efficacy differences—real-world evidence confirms equivalent glycemic control 1.
Do not mix or dilute either formulation with other insulins or solutions 2, 5.
Ensure patient education about the switch to avoid confusion, as the pen devices and appearance may differ despite identical dosing 1.