Insulin glargine vs Insulin degludec: evidence, status and structure
A side-by-side look at Insulin glargine and Insulin degludec, using the data on each VALREXA profile. Neither comparison is a recommendation.
Key differences
- Both sit at the same evidence level: Approved use.
- Both have the same U.S. status category: FDA-approved.
| Insulin glargine | Insulin degludec | |
| Research class | Metabolic Research | Metabolic Research |
| Human evidence | Approved use | Approved use |
| U.S. status | FDA-approved (Lantus, Basaglar, Semglee and others) | FDA-approved (Tresiba, Ryzodeg, Xultophy) |
| 2026 compounding decision | — | — |
| Amino acids | 53 (A + B chains) | 51 (A + B chains) |
| Molecular weight | ~6,063 Da | ~6,104 Da |
| Formula | C₂₆₇H₄₀₄N₇₂O₇₈S₆ | C₂₇₄H₄₁₁N₆₅O₈₁S₆ |
| Sequence | Human insulin with A21 Asn to Gly and two extra B-chain arginines | Human insulin with a C16 fatty diacid attached to B29 Lys |
| Research period | 2000 | 2015 |
| Safety summary | FDA-approved. Errors in dosing cause low blood sugar; use only as prescribed. | FDA-approved. Errors in dosing cause low blood sugar; use only as prescribed. |
How they differ
Both are long-acting basal insulins for the background insulin need between meals. Glargine works by dissolving slowly from a small depot under the skin and lasts about 24 hours. Degludec goes further: its molecules link into long chains that come apart very slowly, giving action beyond 42 hours and steadier levels. In the DEVOTE trial, degludec caused less severe low blood sugar overnight than glargine. For most people both work well; degludec also allows more flexible injection times.
What each one is
Insulin glargine: A long-acting basal insulin analogue that provides steady insulin levels for about 24 hours. Molecular weight, sequence, research history, human evidence and regulatory status.
Insulin degludec: An ultra-long basal insulin that forms slow-release depots and lasts beyond 42 hours. Molecular weight, sequence, research history, human evidence and regulatory status.
Educational reference only. Nothing here is medical advice, a treatment recommendation, or dosing or sourcing guidance. Report an error.