Insulin detemir: A historical perspective on a modern basal insulin analogue

Will the next generation of basal insulins offer clinical advantages?

The 21st century has seen the arrival of several insulin analogue products and the refinement of insulin regimens, with widespread advocacy of continuous titration algorithms and earlier initiation of supplementary insulin therapy (predominantly using basal insulins) in type 2 diabetes. Nevertheless, many insulin-treated diabetes patients remain in poor glycaemic control. This might reflect insufficient titration effort or lax adherence, but these issues could in some cases result from concerns about hypoglycaemia. Certainly there is scope for improving the pharmacokinetic/pharmacodynamic (PK/PD) profile of basal insulin, and three new products offer this prospect. Insulin degludec, now in clinical use, and PEGylated insulin lispro, in development, have greatly extended action profiles that result from two very different, but unique, mechanisms. With once-daily dosing, these insulins produce stable PK/PD profiles at steady state, associated with a low incidence of hypoglycaemia. The feasibility of varied daily dose timing has also been confirmed with insulin degludec. High strength formulations of insulin glargine and insulin degludec offer the prospect of a reduced injection number/volume in high dose users, and in the case of glargine, the PK/PD profile might also be favourably modified. This review considers critically the clinical evidence and expectations we should have for these new basal insulins.

A novel insulin combination of insulin degludec and insulin aspart achieves a more stable overnight glucose profile than insulin glargine: results from continuous glucose monitoring in a proof-of-concept trial

PURPOSE

Insulin degludec coformulated with insulin aspart (as IDegAsp) can cover 24 h basal insulin and postprandial insulin requirements after a main meal with one injection. We compared glycemic stability following IDegAsp or insulin glargine (IGlar) given before the evening meal in patients with type 2 diabetes.

METHODS

A subset of 112 insulin-naïve type 2 diabetes patients from a randomized, parallel-group trial (IDegAsp versus IGlar, each added to metformin) underwent 72 h continuous interstitial glucose (IG) monitoring after 16 weeks of treatment. End points included mean IG concentrations, 2 h postprandial IG increments and postprandial peak, IG fluctuation (summed area above and below mean IG), within-subject coefficient of variation (day-to-day variation) in mean nocturnal IG, and episodes of low (<3.5 mmol/liter) and high (>10 mmol/liter) IG. Values were derived for the entire 72 h, with the nocturnal interval (0001-0559 h) also assessed.

RESULTS

The postdinner IG increment observed with IGlar did not occur with IDegAsp [IDegAsp - IGlar, -1.42 (-2.15, -0.70) mmol/liter]. Nocturnal IG fluctuation was 21% lower with IDegAsp [IDegAsp/IGlar, 0.79 (0.66, 0.96) mmol/liter], with 48% fewer nocturnal high IG episodes [ratio IDegAsp/IGlar, 0.52 (0.32, 0.87)].

CONCLUSIONS

IDegAsp given with the evening meal reduces postdinner glucose excursion and provides more stable nocturnal glycemia as compared with IGlar.

Once-daily initiation of basal insulin as add-on to metformin: a 26-week, randomized, treat-to-target trial comparing insulin detemir with insulin glargine in patients with type 2 diabetes

AIMS

This study assessed the efficacy and safety of once-daily insulin initiation using insulin detemir (detemir) or insulin glargine (glargine) added to existing metformin in type 2 diabetes (T2D).

METHODS

This 26-week, multinational, randomized, treat-to-target trial involved 457 insulin-naïve adults with T2D (HbA1c 7-9%). Detemir or glargine was added to current metformin therapy [any second oral antidiabetic drug (OAD) discontinued] and titrated to a target fasting plasma glucose (FPG) ≤90 mg/dl (≤5.0 mmol/l). Primary efficacy endpoint was change in HbA1c.

RESULTS

Mean (s.d.) HbA1c decreased with detemir and glargine by 0.48 and 0.74%-points, respectively, to 7.48% (0.91%) and 7.13% (0.72%) [estimated between-treatment difference, 0.30 (95% CI: 0.14-0.46)]. Non-inferiority for detemir at the a priori level of 0.4%-points was not established. The proportions of patients reaching HbA1c ≤ 7% at 26 weeks were 38% and 53% (p = 0.026) with detemir and glargine, respectively. FPG decreased ∼43.2 mg/dl (∼2.4 mmol/l) in both groups [non-significant (NS)]. Treatment satisfaction was good for both insulins. Hypoglycaemia, which occurred infrequently, was observed less with detemir than glargine [rate ratio 0.73 (95% CI 0.54-0.98)]. The proportions of patients reaching HbA1c ≤ 7% without hypoglycaemia in the detemir and glargine groups were 32% and 38% (NS), respectively. Weight decreased with detemir [-0.49 (3.3) kg] and increased with glargine [+1.0 (3.1) kg] (95% CI for difference: -2.17 to -0.89 kg).

CONCLUSION

While both detemir and glargine, when added to metformin therapy, improved glycaemic control, glargine resulted in greater reductions in HbA1c, while detemir demonstrated less weight gain and hypoglycaemia.

Insulin degludec: overview of a novel ultra long-acting basal insulin

All the basal insulin products currently available have suboptimal pharmacokinetic (PK) properties, with none reliably providing a reproducible and peakless pharmacodynamic (PD) effect that endures over 24 h from once-daily dosing. Insulin degludec is a novel acylated basal insulin with a unique mechanism of protracted absorption involving the formation of a depot of soluble multihexamer chains after subcutaneous injection. PK/PD studies show that insulin degludec has a very long duration of action, with a half-life exceeding 25 h. Once-daily dosing produces a steady-state profile characterized by a near-constant effect, which varies little from injection to injection in a given patient. Clinically, insulin degludec has been shown consistently to carry a lower risk of nocturnal hypoglycaemia than once-daily insulin glargine, in both basal+bolus and basal-only insulin regimens. The constancy of the steady-state profile of insulin degludec also means that day-to-day irregularities at the time of injection have relatively little PD influence, thereby offering the possibility of greater treatment flexibility for patients.

Future of newer basal insulin

Basal insulin have been developed over the years. In recent times newer analogues have been added to the armanentarium for diabetes therapy. This review specifically reviews the current status of different basal insulins.

Insulin treatment of type 2 diabetes: considerations when converting from human insulin to insulin analogs

Type 2 diabetes mellitus is a highly prevalent disease characterized by insulin resistance, hyperglycemia, and diminished pancreatic β-cell function. Conventional insulin products used to manage this disease include regular human insulin and intermediate-acting human insulin. However, due to several limitations imposed by human insulins, such as onset and duration of action that do not coincide with physiologic needs and increased risk of hypoglycemia, insulin analogs were developed. Because they more closely mimic the physiologic action of endogenous insulin, insulin analogs are associated with more effective glucose control, a lower risk of hypoglycemia, greater convenience, and, in some instances, less weight gain. Switching from human insulin to insulin analogs is easily accomplished. Several studies have demonstrated a high rate of success with patient-initiated, self-adjusted dosing algorithms compared to investigator/clinician-initiated dose adjustments. These studies and several other published guidelines on insulin analogs provide patients and clinicians with information pertaining to better treatment options and can help increase overall patient satisfaction.

The safety and efficacy of adding once-daily insulin detemir to oral hypoglycaemic agents in patients with type 2 diabetes in a clinical practice setting in 10 countries

AIMS

Evaluate the safety and efficacy of once-daily insulin detemir initiated in routine clinical practice in patients with type 2 diabetes mellitus inadequately controlled with oral hypoglycaemic agents (OHAs).

METHODS

This large observational study was conducted in 10 countries. Adverse event data (including hypoglycaemia) and glycaemic control were recorded before and 24 weeks following insulin initiation while patients continued routine clinical management.

RESULTS

In this study, 17 374 patients (53% male) were included. Mean pre-insulin values (±s.d.) were: age 62 ± 12 years; body mass index (BMI) 29.3 ± 5.4 kg/m(2); diabetes duration 10 ± 7 years; haemoglobin A1c (HbA1c) 8.9 ± 1.6%. During the study, 27 patients experienced serious adverse drug reaction, severe hypoglycaemic events or both; and there were 31 episodes of severe hypoglycaemia in 21 patients. After 24 weeks, HbA1c was 7.5 ± 1.2% (change of -1.3%; p < 0.001) and mean weight change was -0.6 kg (confidence interval -0.7, -0.5 kg, p < 0.001). Daily insulin dose increased from 13 ± 6 U (0.16 ± 0.09 U/kg) to 22 ± 16 U (0.27 ± 0.17U/kg) by 24 weeks. Multivariate regression analysis identified several independent demographic and treatment predictors of end of study HbA1c.

CONCLUSIONS

Addition of once-daily insulin detemir to patients with type 2 diabetes mellitus on OHA therapy resulted in few adverse events, significant improvements in glycaemic control, small reductions in weight and low rates of hypoglycaemia. On the basis of this study, concerns about hypoglycaemia or weight gain should not preclude initiation of basal insulin analogues in patients with poor glycaemic control on OHAs.

Incretin-based therapy in combination with basal insulin: a promising tactic for the treatment of type 2 diabetes

Incretin therapies such as dipeptidyl peptidase-4 inhibitors (DPP-4Is) and GLP-1 receptor agonists (GLP-1RAs) have become well-established treatments for type 2 diabetes. Both drug classes reduce blood glucose through physiological pathways mediated by the GLP-1 receptor, resulting in glucose-dependent enhancement of residual insulin secretion and inhibition of glucagon secretion. In addition, the GLP-1RAs reduce gastrointestinal motility and appear to have appetite-suppressing actions and, so, are often able to produce clinically useful weight loss. The glucose-dependency of their glucagon-inhibiting and insulin-enhancing effects, together with their weight-sparing properties, make the incretin therapies a logical proposition for use in combination with exogenous basal insulin therapy. This combination offers the prospect of an additive or synergistic glucose-lowering effect without a greatly elevated risk of hypoglycaemia compared with insulin monotherapy, and any insulin-associated weight gain might also be mitigated. Furthermore, the incretin therapies can be combined with metformin, which is usually continued when basal insulin is introduced in type 2 diabetes. Although the combination of incretin and insulin therapy is currently not addressed in internationally recognized treatment guidelines, several clinical studies have assessed its use. The data, summarized in this review, are encouraging and show that glycaemic control is improved and weight gain is limited or reversed (especially with the combined use of GLP-1RAs and basal insulin), and that the use of an incretin therapy can also greatly reduce insulin dose requirements. The addition of basal insulin to established incretin therapy is straightforward, but insulin dose adjustment (though not discontinuation) is usually necessary if the sequence is reversed.

Insulin initiation in type 2 diabetes: what are the treatment regimen options and how can we best help patients feel empowered?

PURPOSE

This article summarizes treatment regimens and issues involved in initiating insulin therapy in type 2 diabetes (T2D). Progressive deterioration of beta-cell mass and function characterizes the course of T2D. Following diet and exercise, oral antidiabetic drugs (OADs), and incretin therapies, many patients require insulin, but initiation is often delayed until complications develop.

DATA SOURCES

Published guidelines for the management of T2D, primary and review articles, and Food and Drug Administration (FDA) prescribing information.

CONCLUSIONS

The diabetes nurse practitioner should encourage patients to initiate insulin when appropriate; patients need to know that this represents a natural step in treatment, not a personal failing. Initiation often occurs when OADs no longer confer adequate glycemic control. Treatment regimens available include once-daily basal insulin, sometimes with addition of prandial insulin, or premix/biphasic insulin. Insulin analogs confer less risk of hypoglycemia and weight gain, and greater dosing flexibility compared with conventional insulins. Insulin efficacy may be enhanced by continuing metformin and/or incretin therapies, while discontinuing other drugs as appropriate.

IMPLICATIONS FOR PRACTICE

The well-versed diabetes nurse practitioner assists the patient in selecting the most appropriate option for his/her specific needs. It is essential to help patients overcome barriers, including fears of injection pain, public embarrassment, and hypoglycemia risk.

Emerging role of insulin with incretin therapies for management of type 2 diabetes

Type 2 diabetes mellitus (T2DM) is a progressive disease warranting intensification of treatment, as beta-cell function declines over time. Current treatment algorithms recommend metformin as the first-line agent, while advocating the addition of either basal-bolus or premixed insulin as the final level of intervention. Incretin therapy, including incretin mimetics or enhancers, are the latest group of drugs available for treatment of T2DM. These agents act through the incretin axis, are currently recommended as add-on agents either as second-or third-line treatment, without concurrent use of insulin. Given the novel role of incretin therapy in terms of reducing postprandial hyperglycemia, and favorable effects on weight with reduced incidence of hypoglycemia, we explore alternative options for incretin therapy in T2DM management. Furthermore, as some evidence alludes to incretins potentially increasing betacell mass and altering disease progression, we propose introducing these agents earlier in the treatment algorithm. In addition, we suggest the concurrent use of incretins with insulin, given the favorable effects especially in relation to weight gain.

Degludec insulin: A novel basal insulin

This paper reviews a novel insulin analogue, degludec, which has the potential to emerge as an ideal basal insulin. It reviews the limitations of existing basal insulin and analogues, and highlights the need for a newer molecule. The paper discusses the potential advantages of degludec, while reviewing its pharmacologic and clinical studies done so far. The paper assesses the potential role of insulin degludec and degludec plus in clinical diabetes practice.

Treatment of type 1 and type 2 diabetes mellitus with insulin detemir, a long-acting insulin analog

Insulin detemir is a long-acting basal insulin approved for use in patients with type 1 (T1DM) or type 2 diabetes (T2DM). Insulin detemir has demonstrated equivalent glycemic control and hypoglycemic risk when compared to insulin glargine, and insulin detemir has generally but not consistently demonstrated less weight gain than insulin glargine in T2DM. The benefits of basal insulin analogs relative to NPH insulin are well recognized, including less FBG variability, lower risk of hypoglycemia, and less weight gain specifically with insulin detemir. However, NPH insulin continues to be widely prescribed, which may be due in part to economic considerations. While NPH insulin generally costs less per prescription, insulin detemir has been shown to be cost effective compared to NPH insulin as well as insulin glargine. Therefore, insulin detemir is an effective option from both clinical and economic perspectives for patients with T1DM or T2DM who require basal insulin to achieve glycemic control.

Critical appraisal of the safety and efficacy of insulin detemir in glycemic control and cardiovascular risk management in diabetics

Insulin detemir is an analog of human insulin designed to provide a long duration of basal insulin action. This is achieved by protracted absorption from the injection depot, which results in part from increased self-association of insulin detemir molecules and in part from reversible albumin binding. Subsequent albumin binding in the circulation is thought to buffer changes in the effects at target tissues that could otherwise arise from variability in absorption rate. In consequence, insulin detemir has shown a less variable pharmacodynamic profile than alternative basal insulins; this manifests as more consistent temporal glucose reduction profiles in repeat-clamp studies. In clinical trials, insulin detemir has been characterized by consistent risk reductions in hypoglycemia, as well as reduced weight gain in comparison with other basal insulins. Given some recent associations that have been made in prospective and epidemiologic studies between glucose variability and/or hypoglycemia and increased cardiovascular risk, and the long-known association between excess weight and cardiovascular risk, it is possible that the clinical profile of insulin detemir may carry prognostic value with regard to cardiovascular safety, although this is yet to be substantiated. There have also been some concerns raised recently over the use of insulin analogs and cancer risk, but available clinical data and the receptor interaction profile of insulin detemir suggest no excess in risk in comparison with human insulin therapy. Optimal approaches for the clinical use of insulin detemir have been emerging through an increasing clinical study base, and the analog is becoming established as a potentially valuable therapy option.