Yes, Lantus SoloSTAR 100 units/mL is insulin glargine
Lantus SoloSTAR 100 units/mL is the brand name for insulin glargine manufactured by Sanofi—they are the same medication. 1
Understanding the Product
Lantus is simply the brand name that Sanofi uses for their insulin glargine product. The SoloSTAR refers to the specific prefilled pen delivery device that contains this insulin. When you see "Lantus SoloSTAR 100 units/mL," this describes:
- Lantus = Sanofi's brand name for insulin glargine
- SoloSTAR = The disposable prefilled pen device
- 100 units/mL (U-100) = The concentration of insulin glargine
The FDA-approved label explicitly states this is "insulin glargine injection" 1.
Important Distinctions to Understand
Different Concentrations of the Same Insulin
While Lantus SoloSTAR 100 units/mL and other insulin glargine products contain the same active ingredient (insulin glargine), there are clinically important differences between formulations:
- U-100 glargine (Lantus): Standard concentration, available as vials and SoloSTAR pens 2
- U-300 glargine (Toujeo): Three times more concentrated, has a longer duration of action but modestly lower efficacy per unit administered 3
These are NOT interchangeable unit-for-unit. U-300 glargine requires higher total daily doses to achieve equivalent glycemic control compared to U-100 4.
Biosimilar Products
Several biosimilar or follow-on products of insulin glargine U-100 are now available at lower costs 2, 5. These include products like Basaglar (LY IGlar) which have demonstrated similar pharmacokinetic and pharmacodynamic properties to Lantus in clinical trials 6, 7, 8. The 2025 ADA guidelines list these as "glargine follow-on products" with median costs of $118-$323 per 1,000 units compared to branded Lantus at $136 per 1,000 units 3.
Critical Safety Considerations
Never Mix or Substitute Without Medical Supervision
- Do not mix insulin glargine with other insulins due to its low pH diluent 9, 1
- Do not dilute or mix with any other solution 1
- Any change between insulin types or manufacturers should occur under close medical supervision with increased glucose monitoring 3, 5
Dosing Errors to Avoid
- Accidental mix-ups between insulin products can occur—always check insulin labels before injection 1
- When switching between U-100 and U-300 formulations, expect to need different total daily doses to achieve the same glycemic control 3, 4
- U-300 glargine showed patients required significantly more units daily than U-100 to achieve equivalent efficacy 4
Device-Specific Information
The SoloSTAR pen is a single-patient-use prefilled pen that should never be shared between patients, even if the needle is changed 1. After first use, store at room temperature below 86°F and discard after 28 days 1.
Clinical Equivalence of Biosimilars
Research demonstrates that biosimilar insulin glargine products have similar pharmacokinetic and pharmacodynamic profiles to Lantus. Studies show the 90% confidence intervals for all PK parameters (AUC, Cmax) fall within 80-125%, meeting regulatory requirements for biosimilarity 6, 8, 10. In clinical practice, these biosimilars provide comparable glucose control and safety to branded Lantus 7.