Human Regular 500 units/mL Insulin Therapy: A Review of Clinical Evidence and New Delivery Options

Factors Affecting Performance of Insulin Pen Injector Technology: A Narrative Review

BACKGROUND

Insulin treatment is an essential hormone replacement therapy for the survival of people with type 1 diabetes and is often used for treatment in type 2 diabetes, particularly as the disease progresses. Advances in insulin therapy have been made since its discovery, including production of human insulin and development of insulin analogs with improved efficacy and safety profiles. The different types of available insulin formulations allow health care professionals to personalize treatment to an individual's needs. Generally, insulin requires parenteral administration via subcutaneous injection owing to very low oral bioavailability.

METHODS

This article reviews the human, technological, economical, and regulatory factors affecting the performance of insulin pens and the relationship between them. Opportunities and challenges that insulin pen injections may encounter in the future are also considered.

RESULTS

Insulin delivery devices, together with other factors, influence dose accuracy, convenience, and quality of life, contributing to easier medication administration with high efficacy and safety. For patients, ease of use, fast and accurate drug delivery, and painless injection are the most valuable features of an insulin injection device. For manufacturers, technological feasibility and economic viability also need to be considered when developing injection devices.

CONCLUSION

Insulin pen injectors are generally preferred over vial and syringe, although access may be limited in some health care systems. Insulin pen injectors can adapt to different insulin regimens and formulations and have the potential to acquire dosing data in real time.

Treatment Patterns and Outcomes Before and After Humulin R U-500 Initiation Among US Patients with Type 2 Diabetes Previously Prescribed ≤ 200 Units/day of U-100 Insulin

INTRODUCTION

Humulin R U-500 (U-500R) utilization has increased in the past few years, raising concerns as U-500R is indicated only for patients requiring > 200 units of insulin. Thus, evidence of dispensed total daily dose (dTDD) > 200 units of prior U-100 insulin based on pharmacy claims is increasingly used as a criterion to determine appropriate switching to U-500R by payers. The study compared the treatment patterns and outcomes before and after U-500R initiation among patients who were identified with ≤ 200 units/day U-100 insulin fill in order to understand the appropriateness of switching.

METHODS

Patients with type 2 diabetes who initiated U-500R (index date = first fill) with ≤ 200 units/day pre-index dTDD and > 200 units/day post-index dTDD were identified in a Veterans Health Administration dataset between 1 January 2014 and 30 June 2017. Descriptive analysis was conducted on treatment patterns (dTDD, insulin dosage [units/kg], adherence, number of prescription fills) and clinical outcomes (HbA1c, symptomatic hypoglycemic events). Associations between U-500R exposure and outcomes were evaluated using mixed-effects models. Subgroups of U-500R syringe and KwikPen users were analyzed separately.

RESULTS

Among 1191 U-500R initiators identified in the study the mean dTDD increased from the pre- to post-index periods (147.2 vs 346.3; p < 0.0001). The mean HbA1c decreased from pre- to post-initiation (9.6% vs 8.6%; p < 0.0001), and symptomatic hypoglycemia events per patient per year increased (2.0 vs 3.3, p < 0.0001). Mixed-effects models confirmed the significance of the changes (p < 0.0001). Device subgroups followed similar trends.

CONCLUSIONS

U-500R initiation was associated with large dTDD increases, improved glycemic control, and modest increases in hypoglycemia events, suggesting U-500R initiation may have corrected previous treatment compliance issues. Imposing dTDDs > 200 units before switching to U-500R criterion could hurt the opportunities for patients who need a simplified regimen for better outcomes.

Pharmacokinetics and Pharmacodynamics of Human Regular U-500 Insulin Administered via Continuous Subcutaneous Insulin Infusion Versus Subcutaneous Injection in Adults With Type 2 Diabetes and High-Dose Insulin Requirements

INTRODUCTION

Human regular U-500 insulin (U-500R) is approved for subcutaneous (SC) injection in patients with diabetes requiring >200 units/day of insulin. Here, pharmacokinetic and pharmacodynamic (PK/PD) profiles following U-500R administered by continuous subcutaneous insulin infusion (CSII) and SC injection in adults with type 2 diabetes (T2D) on high-dose insulin were studied.

METHODS

In this randomized, crossover, euglycemic clamp study, patients received a 100-unit bolus of U-500R via SC injection or CSII with basal infusion using a U-500R specific pump. PK parameters were estimated using non-compartmental methods. PD estimates were derived from the glucose infusion rate during the euglycemic clamp procedure.

RESULTS

When corrected for the basal infusion, the PK profiles for the 100-unit bolus of U-500R were similar for CSII and SC injection. Without correction for basal infusion, PK and PD profiles showed a greater insulin concentration and effect when U-500R was administered via CSII compared to SC injection, primarily due to basal insulin infusion for CSII. The ratio of geometric least squares AUC_0-tlast means SC:CSII (90% CI) is 0.857 (0.729, 1.01) with correction (mean AUC_0-tlast: 5230 pmol*L/h [SC injection] and 6070 pmol*L/h [CSII, with correction]) and 0.424 (0.361, 0.499) without correction (mean AUC_0-tlast: 12300 pmol*L/h [CSII, without correction]). Median time-to-peak insulin concentration was six hours (range 0.5-8 hours) via SC injection and five hours (0.5-12 hours) via CSII.

CONCLUSIONS

In adults with T2D on high-dose insulin, U-500R PK/PD parameters were similar for a 100-unit bolus when given by SC injection or CSII via a U-500R pump.

Treatment patterns and outcomes before and after human regular U-500 insulin initiation via KwikPen® among US veterans with type 2 diabetes mellitus

INTRODUCTION

A dedicated Humulin R U-500 (U-500R) prefilled disposable insulin pen (KwikPen) became available in 2016, yet limited evidence exists on treatment patterns and outcomes of U-500R via KwikPen (U500-KP).

METHODS

This is a retrospective observational study among adults with ≥2 claims for type 2 diabetes initiating U500-KP (index date: first claim) identified in Veterans Health Administration database. Treatment patterns and outcomes were evaluated in 9-month pre- and post-index periods, including dispensed total daily insulin dosage derived from claims expressed in units (dTDD) and units/kg, HbA1c, symptomatic hypoglycemia, and body weight. Multivariable modeling was used to confirm the associations between U500-KP initiation and outcomes.

RESULTS

A total of 647 U500-KP initiators were identified. The mean age was 64 years, and mean Quan-Charlson Comorbidity-index score was 3.8. Before U500-KP initiation, 62% of patients had dTDD ≤ 200 units with mean A1c 9.5%. Mean dTDD increased from 188.2 to 269.9 units after U500-KP initiation with mean A1c decreased by 0.83% (SD = 1.67) and mean weight gain of 1.5 kg (SD = 6.74). Hypoglycemia events increased from 4.3 to 5.3 (p < 0.05) per person per year.

CONCLUSIONS

Initiation of U500-KP brought significant improvement in dispensed insulin dose and glycemic control accompanied by moderate increases in hypoglycemia and weight.

Treatment Patterns and Outcomes, Before and After Humulin R U-500 Initiation, Among High-Dose Type 2 Diabetes Mellitus Patients in the United States

OBJECTIVE

Severely insulin-resistant type 2 diabetes (T2D) patients face unique treatment challenges. Humulin R U-500 (U-500R) as insulin monotherapy with both basal/bolus properties addresses these challenges, although it remains understudied. This retrospective study compared real-world patient characteristics, treatment patterns, and outcomes before and after U-500R initiation.

METHODS

Adults with T2D on dispensed doses of >180 units/d U-500R monotherapy (index date=first fill) with ≥9-month continuous enrollment both pre- and post-index date and ≥180 units/d insulin pre-index were identified using Veterans Health Administration data (January 1, 2014-January 30, 2017). Overall group was further stratified into elderly and 201 to 300 units dispensed total daily dose (dTDD) subgroups. Syringe and KwikPen users were separately analyzed as subcohorts. Treatment patterns (dTDD), insulin dosage (units/kg), proportion of days covered (PDC) with insulins, and outcomes (HbA1c and hypoglycemic events) were descriptively evaluated, with regression models used to confirm associations between exposure and outcomes.

RESULTS

Among 951 U-500R initiators (overall group), mean dTDD (248.5 vs 392.1), percentage of patients with insulin dosage >2 units/kg (38.6% vs 88.1%), and mean PDC (73% vs 77%) significantly increased from the pre- to post-index periods (all P<.001). Changes in HbA1c (9.3% vs 8.5%; P<.0001) and hypoglycemia events per patient per year (2.1 vs 3.1, P<.0001) were statistically significant and confirmed by regression models (P<.0001). Subgroups (elderly, 492; 201 to 300 units, 148) and device subcohorts (syringe, 714; KwikPen, 244) showed similar trends.

CONCLUSION

U-500R initiation was associated with significantly improved treatment compliance patterns and glycemic control, with modest increase in hypoglycemia events.