Short answer: Both are premixed insulins for adults with diabetes, typically injected twice a day within 15 minutes before a meal.12 Humalog Mix75/25 is 75% insulin lispro protamine and 25% insulin lispro. NovoLog Mix 70/30 is 70% insulin aspart protamine and 30% insulin aspart. The Humalog Mix75/25 label has no trial results; neither label compares them. Neither has a boxed warning.
| Humalog Mix75/25 | NovoLog Mix 70/30 | |
|---|---|---|
| What is in it | 75% insulin lispro protamine, 25% insulin lispro1 | 70% insulin aspart protamine, 30% insulin aspart2 |
| Approved for | Adults with diabetes1 | Adults with diabetes; not for diabetic ketoacidosis2 |
| When injected | Within 15 minutes before a meal, typically twice daily1 | Within 15 minutes before a meal, typically twice daily; in type 2 also after the meal starts2 |
| Action (healthy subjects) | Median most effect about 2 hours; still lowering at 22 hours, the end of the study1 | Starts in 10 to 20 minutes; mean peak 2.7 hours; may last up to 24 hours2 |
| Trials in the label | None; the label compares its action with Humulin 70/30 in clamp studies1 | 12 weeks vs Novolin 70/30; 34 and 28 weeks in type 2 with tablets2 |
| Side-effect rates | None given; reactions listed without percentages1 | Single-arm 3-month trial: low blood sugar 69% (type 1) and 47% (type 2)2 |
| Forms | 10 mL vial; 3 mL KwikPen1 | 10 mL vial; 3 mL FlexPen2 |
| Opened pen | 10 days at room temperature, not refrigerated1 | 14 days at room temperature, not refrigerated2 |
| Mixing, pump, vein | Not mixed, not in a pump, not into a vein1 | Not mixed, not in a pump, not into a vein2 |
The Humalog Mix75/25 label has no clinical studies section. It reports clamp studies in healthy people showing that the quick start of Humalog is kept in the mix and that its duration is similar to Humulin 70/30.1
The NovoLog Mix 70/30 label reports a 3-month trial against Novolin 70/30, each twice daily: HbA1c went from 8.4% to 8.4% vs 8.5% to 8.3% in type 1, and 8.1% to 7.9% vs 8.2% to 8.1% in type 2. Added to metformin and pioglitazone in people new to insulin, it lowered HbA1c 1.6% vs 0.3% on tablets alone over 24 weeks, and against once-daily insulin glargine it lowered HbA1c 2.7% vs 2.4% over 28 weeks.2 These numbers come from separate trials with different people, lengths and methods, so they are not a head-to-head comparison.
Both are white, cloudy suspensions mixed by rolling and turning right before each dose, and each dose is meant to cover 2 meals or a meal and a snack. Both labels say the fixed proportions do not allow separate basal and mealtime dose changes, and that a different dose may be needed when switching from another insulin. Neither gives a missed-dose instruction.12
Which, if either, fits is for your prescriber. More detail: Humalog Mix75/25 side effects, NovoLog Mix 70/30 side effects, the Humalog Mix75/25 and NovoLog Mix 70/30 dosing schedules and Humalog vs NovoLog: what is different between the two mealtime insulins?.