Introduction

Type 2 diabetes is a progressive disease. The addition of insulin to provide mealtime coverage is needed when oral antidiabetes agents (OADs) and a basal regime of insulin are no longer enough to establish or maintain glycemic control [1]. Existing basal bolus regimens offer both basal and precise postprandial glucose control, but as separate injections [2]. Many patients are reluctant to start with a basal and bolus insulin regimen because of its complexity, the added need to calculate a prandial dose, the need for two injections, and a fear of hypoglycemia [3]. IDegAsp, is a modern insulin co-formulation approved in more than 70 countries across the world [4]. It is a preformulated fixed-ratio combination of rapid-acting insulin aspart (IAsp) (30%) and ultra-long acting insulin degludec (IDeg) (70%). IDegAsp is marketed as a prefilled disposable pen, as well as in pen fills that can be used with durable pens [5].

Versatility and Flexibility

IDegAsp is a unique formulation that shows great versatility and flexibility. IDegAsp works as both premix and basal plus regimens, and can substitute for basal bolus regimens as well. It can be used once daily, twice daily, or as part of a thrice daily regimen (one IDegAsp and two IAsp doses). Thus, IDegAsp allows freedom and flexibility in diabetes care [6].

Size exclusion chromatography studies of IDegAsp indicate that IDeg and IAsp exist as stable dihexamers and hexamers, respectively, in the formulation [7]. Moreover, at steady state, the prandial and basal glucose-lowering effects of IDeg and IAsp were distinct and clearly separated. A clear dose–response relationship was observed in patients with type 1 and type 2 diabetes treated with IDegAsp [8]. The glucose-lowering effects of basal and prandial components of IDegAsp are maintained in elderly (≥ 65 years of age) patients with type 1 diabetes [9]. In addition, the PK and clearance of IDeg and IAsp are not affected by mild, moderate, or severe renal or hepatic impairment [8]. The presence of two distinct insulin analogues as a soluble co-formulation of a basal component with an ultra-long duration of action makes IDegAsp an advance over earlier premix insulins. To overcome the burden of multiple daily injections, co-formulating basal and bolus insulins in a single injection could allow a simple regimen with fewer injections [6].

Evidence from Randomized Controlled Trials

This article is based on previously conducted studies and does not contain any studies with human participants or animals performed by any of the authors.

The efficacy and safety of IDegAsp were evaluated in the BOOST clinical trial program. BOOST was a phase 3 trial designed to represent a large population of diabetes from various geographic areas. IDegAsp has been studied in both type 1 and type 2 diabetes and it has been used in once daily or twice daily regimen [10,11,12,13,14,15].

In a Japanese study, comparing IDegAsp once daily with insulin glargine (IGlar) once daily for 26 weeks in insulin-naïve type 2 diabetes patients, IDegAsp demonstrated superiority in terms of HbA1c reduction, which was achieved as a result of the reduction in fasting plasma glucose (FPG) and evening meal postprandial glucose (PPG). The superiority was realized with less risk of nocturnal and overall hypoglycemia with IDegAsp [10].

IDegAsp has also been studied in a twice daily regimen in comparison to basal bolus therapy in type 2 diabetes mellitus (T2DM) patients. IDegAsp achieved similar efficacy with less risk of hypoglycemia, with a reduction in the overall dose and fewer self-monitoring blood glucose values required compared to the basal (IDeg) bolus (IAsp) regimen [11].

When compared to premix, IDegAsp has consistently demonstrated effective glycemic control with superior FPG reduction and less risk of both nocturnal and overall hypoglycemia [12, 13].

In a study performed in type 1 diabetes, comparing IDegAsp once daily with insulin detemir (IDet) + mealtime IAsp, both the arms revealed that IDegAsp achieved similar HbA1c with better FPG reduction and less risk of nocturnal and overall hypoglycemia [14].

Real-World Evidence

The efficacy and tolerability data of IDegAsp are supported by real-world evidence across the globe. Kaneko et al. illustrated that IDegAsp provided a simple, helpful intensification for poorly controlled T2DM patients on OADs, special populations in whom it is difficult to escalate/intensify insulin therapy, and T2DM patients dosed with conventional premix [15]. Kalra and Baruah presented 1-year data from India highlighting the efficacy, safety, and tolerability of IDegAsp in patients with poor glycemic control [6]. Results from the major clinical studies on IDegAsp are summarized in Table 1.

Table 1 Summary of clinical trials and real-world evidence on insulin degludec/insulin aspart
Full size table

All the evidence suggests that a co-formulation of basal and bolus insulin allows for basal and prandial coverage with fewer injections compared to basal and bolus therapy whilst offering simplicity and convenience. The comprehensive fasting and prandial control achieved with this preparation is especially useful for people who consume high carbohydrate meals, as in Africa, Asia, and Latin America.

Eminent Experience

An earlier multinational consensus identified and defined seven patient profiles in which IDegAsp can be a preferred choice of insulin preparation. Of these profiles, five relate to type 2 diabetes, and two to type 1 diabetes [16]. IDegAsp is described as an insulin for initiation in two, intensification in three, and interchange in two clinical profiles. A South Asian consensus statement provides pragmatic guidance regarding the safe and effective use of IDegAsp during Ramadan [17].

Concordance

Current guidelines released by the American Diabetes Association (ADA) acknowledge the role of premix insulin in the management of type 2 diabetes. Both premix and basal plus insulin regimens are suggested as an option for intensification of insulin. Intensive insulin regimes are also listed as a therapeutic choice in persons presenting with hyperglycemic symptoms or cachexia [18].

As discussed earlier, the versatile IDegAsp preparation can be used as a premix, basal plus, or basal bolus regimen. It can also be used for once daily initiation of insulin in place of basal insulin. Therefore, there is a need to revisit the use of IDegAsp and highlight its concordance with current ADA guidelines.

While the earlier consensus has described the clinical utility of IDegAsp in detail, a focus is required on earlier use of appropriate insulins. This implies initiation of the right insulin at the right time. This multinational consensus, therefore, seeks to define the situations where IDegAsp can be used for initiation of insulin therapy. It also suggests simple clinical tips that will help promote efficient implementation of IDegAsp.

Consensus: Initiation with Insulin Degludec/Aspart (IDegAsp)

Indications

  • The consensus group recommends the use of IDegAsp for initiation of insulin in

    • Drug-naïve persons with

    • Symptoms of hyperglycemia.

    • High carbohydrate diet.

    • High HbA1c.

    • High postprandial excursion.

    • Insulin-naïve persons with inadequate response to metformin, dual or triple oral therapy.

    • Long-acting sulfonylureas and IDegAsp, if used together, should be administered at antipodal meals.

Administration and Titration

  • The consensus group recommends the use of IDegAsp for insulin initiation in once daily or twice daily subcutaneous dosage, depending upon

    • Meal pattern and quantity

    • Gluco-phenotype (glucose profile)

  • The starting dose of IDegAsp is usually 10 U or 0.1–0.2 U/day, but will vary according to

    • Severity of hyperglycemia

    • Risk of hypoglycemia

    • Meal pattern and quantity

    • Weight of the patient

The consensus group recommends titration of IDegAsp to be performed using a simple 2-0-2 algorithm (add 2 U if target fasting or premeal glucose is not achieved; zero change if target is achieved; reduce by 2 U if hypoglycemia occurs).

  • IDegAsp use should be monitored by regular self-monitoring of blood glucose

    • Twice weekly when glycemic control is unstable, hypoglycemia is anticipated, or urgent resolution of hyperglycemia is needed.

    • Once weekly when glycemic control is stable and no fluctuations are anticipated.

    • More frequently if glycemic control is brittle.

    • Once prebreakfast and predinner control is achieved, postprandial glucose monitoring can be done to titrate doses further.

Advantages

As compared to other insulin regimens and preparations, IDegAsp provides

  • Glycemic control better or equivalent to

    • Basal regimen, if used once daily

    • Basal plus regimen, if used once daily

    • Basal bolus regimen, if used twice daily

    • Premix therapy

  • Flexibility in timing of administration

  • Lower risk of

    • Hypoglycemia

    • Nocturnal hypoglycemia

Special Situations

The consensus group recommends IDegAsp should not be used

  • In pregnancy and lactation

  • As the only insulin in diabetic ketoacidosis

  • Intravenously

The consensus group recommends IDegAsp to be used safely in special situations such as

  • Shift workers/those with erratic meal patterns

  • Ramadan fasting

  • Renal impairment

  • Hepatic impairment

  • Elderly population

The consensus group recommends IDegAsp to be initiated as part of a three-dose regimen (IAsp–IAsp–IDegAsp) in

  • Type 1 diabetes

  • Persons in whom early correction of hyperglycemia is required

Conclusion

This consensus provides information on the efficacy, safety, and ease of administration of IDegAsp in comparison with other insulin regimens and highlights the benefits of IDegAsp. It also provides a simple consensus for the use of IDegAsp in various populations with an algorithm for dose titration.