Converting Basaglar to Lantus: Direct 1:1 Unit-for-Unit Conversion
When switching from Basaglar (insulin glargine) to Lantus (insulin glargine), convert on a 1:1 unit-for-unit basis without dose adjustment, as both are identical insulin glargine formulations with equivalent pharmacokinetics and clinical efficacy. 1
Standard Conversion Protocol
- Convert the total daily dose of Basaglar directly to the same dose of Lantus administered at the same time of day 2, 1
- Maintain the same once-daily or twice-daily dosing schedule that was used with Basaglar 2
- No dose reduction or adjustment is necessary for standard-risk patients, as real-world evidence demonstrates equivalent glycemic control with identical dosing 1
Post-Conversion Monitoring
- Monitor fasting blood glucose daily during the first 1-2 weeks after conversion to confirm adequate dosing 2
- Assess for hypoglycemia at every clinical contact during the transition period 2
- If hypoglycemia occurs, reduce the dose immediately by 10-20% and reassess 2
High-Risk Patient Modifications
For patients at elevated hypoglycemia risk (elderly, renal impairment, history of severe hypoglycemia):
- Reduce the converted dose by 10-20% from the total daily Basaglar dose 2
- Implement more frequent glucose monitoring during the first week 2
- Titrate upward by 2 units every 3 days based on fasting glucose values if needed to reach target of 80-130 mg/dL 3
Evidence Supporting 1:1 Conversion
A real-world retrospective study of 225 patients (81% with type 2 diabetes) converted from Lantus to Basaglar demonstrated:
- No significant difference in mean insulin dose at 6 months (46.3 vs 45.9 units/day, P=0.52) 1
- No significant differences in A1C change at any time point through 12 months 1
- Equivalent glycemic outcomes with identical dosing requirements 1
This evidence confirms that Basaglar and Lantus are bioequivalent formulations requiring no dose adjustment during conversion.
Common Pitfall to Avoid
- Do not arbitrarily reduce the dose when converting between these identical insulin glargine formulations in standard-risk patients, as this will result in inadequate glycemic control 1
- The only exception is high-risk patients where a 10-20% reduction is appropriate for safety 2
Cost Considerations
While not affecting the conversion dose, Lantus typically has higher acquisition costs than Basaglar, though both provide equivalent clinical outcomes 1