Insulin aspart
Also known as: Asp(B28) insulin, Fiasp, IAsp, Insulin aspart, NovoLog, NovoRapid
Source Insulin aspart at Peptiology
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Summary
Insulin aspart is a rapid‑acting insulin analogue approved for prescription use in the treatment of diabetes mellitus. It is administered before meals (or via an insulin pump) to control post‑prandial blood glucose as part of a basal‑bolus regimen. Its faster absorption compared with regular human insulin helps achieve tighter glycaemic control and lower HbA1c levels.
Mechanism of Action
Insulin aspart differs from human insulin by a single amino‑acid substitution at position B28 (proline → aspartic acid). This reduces self‑association of the molecule, allowing quicker dissociation into monomers after subcutaneous injection. The rapid appearance of active insulin in the circulation leads to an earlier onset of glucose‑lowering action, matching the rise in post‑meal glucose and facilitating tighter post‑prandial control.
What the Research Shows
Randomised trials and systematic reviews provide the bulk of evidence for insulin aspart. A 2014 meta‑analysis of five RCTs (1,758 participants) showed that biphasic insulin aspart (BIAsp 30) added to oral agents lowered HbA1c more than basal insulin glargine (mean difference –0.21 %) and reduced post‑prandial glucose increments, without increasing severe hypoglycaemia, though it was associated with modest weight gain. The ONWARDS 4 phase 3 trial (582 participants) demonstrated that, when used as the bolus component with once‑weekly insulin icodec, insulin aspart achieved HbA1c reductions comparable to daily glargine, with similar hypoglycaemia rates. In the EXPECT study of pregnant women with type 1 diabetes, insulin aspart combined with either degludec or detemir showed non‑inferior glycaemic control and no new safety signals. A head‑to‑head trial (SUSTAIN 11) compared thrice‑daily insulin aspart to weekly semaglutide as add‑on to basal insulin; while semaglutide achieved greater HbA1c reduction and weight loss, insulin aspart provided effective glycaemic control with low severe hypoglycaemia. A Japanese review highlighted its rapid absorption, better post‑prandial control, and comparable overall safety to human insulin.
Reported Benefits
Clinical data indicate that insulin aspart provides faster onset of action, leading to superior post‑prandial glucose control and modest HbA1c reductions compared with some basal insulins. It can be used flexibly with multiple daily injections or continuous subcutaneous infusion, supporting intensive basal‑bolus regimens. Overall safety appears comparable to regular human insulin, with similar rates of hypoglycaemia and adverse events.
Limitations of the Evidence
Evidence is largely derived from short‑ to medium‑term trials; long‑term cardiovascular or microvascular outcomes are not well established. Weight gain was observed in studies using biphasic aspart formulations. Many trials were open‑label, which may introduce bias, and head‑to‑head comparisons with newer basal insulins are limited. Data in special populations (e.g., children, elderly) are sparse.
Safety Considerations
Insulin aspart has a safety profile similar to human insulin, with hypoglycaemia being the most common adverse effect, particularly if meals are delayed or doses are mismatched. Reported serious adverse events are rare and comparable to other insulin types. Weight gain may occur, especially with biphasic formulations. Caution is advised in patients with renal or hepatic impairment, and dose adjustments may be needed during illness or pregnancy.
How It Is Administered
Insulin aspart is administered subcutaneously, typically 0–5 minutes before meals, or immediately after a meal if needed. It is also formulated for use in continuous subcutaneous insulin infusion (insulin pump) and can be given intravenously in hospital settings for rapid glucose control. Formulations are supplied as a clear solution for injection.
Routes of Administration
Goals & Uses
- Diabetic ketoacidosis treatment (IV)Emergency Glycemic ManagementModerate
- Type 2 diabetes mellitus managementGlycemic ManagementHigh
- Glycemic controlDiabetesHigh
- Type 1 diabetes mellitus managementGlycemic ManagementHigh
- Gestational diabetes / diabetes in pregnancyGlycemic ManagementHigh
- Postprandial glucose controlGlycemic ManagementHigh
Contraindications
- Known hypersensitivity to insulin aspart or excipientsAllergicHigh
- Hypersensitivity to insulin aspart or excipientsImmunologicHigh
- Hypoglycemia (active episode)MetabolicHigh
- HypoglycemiaMetabolicHigh
Adverse Effects
- HypokalemiaElectrolyteUncommon
- HypoglycemiaMetabolicCommonAbnormally low blood glucose
- Peripheral edemaFluid BalanceUncommonSwelling of the arms or legs
- Injection site reactionsLocalCommon
- Allergic reactions / anaphylaxisImmunologicRare
- Weight gainMetabolicCommonIncrease in body weight
- LipodystrophyDermatologicUncommon
Drug Interactions
- Thiazolidinediones (e.g., pioglitazone)Moderate
- Salicylates (high-dose aspirin)Low
- Beta-blockersModerate
- AlcoholModerate
- CorticosteroidsModerate
- MAO inhibitorsModerate
- ACE inhibitorsLow
Population Constraints
- Pediatrics (<6 years)AgeRelative
- PregnancyReproductive SafetyRelative
- Hepatic impairmentOrgan FunctionRelative
- Renal impairmentOrgan ImpairmentRelative
- Elderly patientsAgeRelative
- Pediatric patients (<2 years)AgeRelative
Regulatory Status
- European UnionApprovedApproved: type 1 diabetes mellitus, type 2 diabetes mellitusMarketed as NovoRapid
- United StatesApprovedApproved: type 1 diabetes mellitus, type 2 diabetes mellitusMarketed as NovoLog
- United KingdomApprovedApproved: type 1 diabetes mellitus, type 2 diabetes mellitusAvailable under NHS formularies
Approved in US (FDA), EU (EMA), and many other jurisdictions; indicated for mealtime insulin therapy.
Evidence & Sources
- Journal ArticleModerateMathieu C, et al.2023-01-01T00:00:00.000000Z
- Journal ArticleHighRys P, et al.2014-01-01T00:00:00.000000Z
- Journal ArticleModerateMathiesen ER, et al.2023-01-01T00:00:00.000000Z
- Journal ArticleModerateKellerer M, et al.2022-01-01T00:00:00.000000Z
- Journal ArticleModerateNamba M2001-01-01T00:00:00.000000Z
Frequently Asked Questions
How quickly does insulin aspart start to work?
Because of its reduced self‑association, insulin aspart begins to lower blood glucose within 5–10 minutes after subcutaneous injection, reaching peak effect around 1 hour and lasting 3–5 hours.
What are the most common side effects?
The main side effect is hypoglycaemia, especially if the dose does not match carbohydrate intake. Other reported events include injection‑site reactions and modest weight gain, but overall safety is similar to regular human insulin.
Can insulin aspart be used during pregnancy?
Insulin aspart is commonly used as the mealtime component in basal‑bolus regimens for pregnant women with diabetes. Clinical trials combining it with basal insulins (e.g., degludec, detemir) have shown no additional safety concerns, but dosing should be individualized under medical supervision.
Is insulin aspart compatible with insulin pumps?
Yes, insulin aspart is formulated for continuous subcutaneous infusion and is approved for use in insulin pump therapy, providing rapid‑acting coverage for meals and correction doses.
Does insulin aspart cause weight gain?
Weight gain has been reported, particularly with biphasic insulin aspart formulations, but the magnitude is generally modest and comparable to other insulin therapies. Lifestyle and diet management can help mitigate this effect.
What is Insulin aspart?
Insulin aspart is a rapid‑acting insulin analogue approved for prescription use in the treatment of diabetes mellitus. It is administered before meals (or via an insulin pump) to control post‑prandial blood glucose as part of a basal‑bolus regimen. Its faster absorption compared with regular human insulin helps achieve tighter glycaemic control and lower HbA1c levels.
What is Insulin aspart used for?
Insulin aspart is educationally associated with: Diabetic ketoacidosis treatment (IV), Type 2 diabetes mellitus management, Glycemic control, Type 1 diabetes mellitus management, Gestational diabetes / diabetes in pregnancy, Postprandial glucose control. Educational only — not medical advice.
How is Insulin aspart administered?
Recorded routes of administration: Continuous Subcutaneous Infusion (insulin Pump), Intravenous, Subcutaneous.
What are the potential side effects of Insulin aspart?
Reported adverse effects include: Hypokalemia, Hypoglycemia, Peripheral edema, Injection site reactions, Allergic reactions / anaphylaxis, Weight gain, Lipodystrophy. This list is not exhaustive — consult a qualified clinician.
Who should avoid Insulin aspart?
Recorded contraindications: Known hypersensitivity to insulin aspart or excipients, Hypersensitivity to insulin aspart or excipients, Hypoglycemia (active episode), Hypoglycemia. Consult a qualified clinician before use.