Paris Roach

Time-Action Profiles of Novel Premixed Preparations of Insulin Lispro and NPL Insulin

OBJECTIVE To study the pharmacodynamic properties of three premixed formulations of the rapid-acting insulin analog insulin lispro and its protamine-retarded preparation, neutral protamine lispro (NPL) insulin. RESEARCH DESIGN AND METHODS In this open, single-center, euglycemic glucose clamp study, 30 healthy volunteers (12 women, 18 men) aged 27 ± 2 years (mean ± SD), whose BM1 was 23.0 ± 2.3 kg/m2, received subcutaneous injections of 0.3 U/kg body wt of insulin mixture (high-mixture 75/25, mid-mixture 50/50, or low-mixture 25/75 insulin lispro/NPL insulin), insulin lispro, or NPL insulin on one of the five study days in randomized order. Glucose infusion rates were determined over a period of 24 h after administration. RESULTS Maximal metabolic activity decreased after subcutaneous injection of the mixtures with lower insulin lispro content; however, the time point of maximal and of early halfmaximal metabolic activity was comparable among the three mixtures. Higher proportions of insulin lispro resulted in higher values for area under the curve within the first 360 min after injection and a more rapid decline to late half-maximal activity. Serum insulin concentrations showed a similar pattern. CONCLUSIONS This study shows that the pharmacodynamic and pharmacokinetic properties of insulin lispro are preserved in stable mixtures with NPL insulin.

Improved postprandial blood glucose control and reduced nocturnal hypoglycemia during treatment with two novel insulin lispro-protamine formulations, insulin lispro Mix25 and insulin lispro Mix50

The objective of this 6-month, open-label, randomized, two-period crossover study was to compare glycemic control when patients were treated with (1) 2 manufactured premixed insulin formulations containing insulin lispro and a novel insulin lispro-protamine formulation, neutral protamine lispro (NPL), and (2) 2 manufactured premixed human insulin formulations, human insulin 50/50 and human insulin 30/70. One hundred individuals, 37 with type 1 diabetes mellitus (12 females, 25 males; mean age, 39.4 years; mean body mass index [BMI], 24.8; mean duration of diabetes, 12.9 years) and 63 with type 2 diabetes mellitus (33 females, 30 males; mean age, 59.0 years; mean BMI, 28.4; mean duration of diabetes, 12.6 years), were treated with insulin lispro mixtures. Insulin lispro Mix50 (50% insulin lispro/50% NPL) and human insulin 50/50 (50% regular insulin/50% neutral protamine Hagedorn [NPH] insulin) were administered before breakfast; insulin lispro Mix25 (25% insulin lispro/75% NPL) and human insulin 30/70 (30% regular insulin/70% NPH) were administered before dinner. Blood glucose (BG), hypoglycemic episodes (hypoglycemic signs or symptoms or BG <3.0 mmol/L), insulin dose and timing of dose before meals, and hemoglobin A1c were measured. Mean doses of insulin lispro and human insulin mixtures were similar overall and for both diabetes subgroups. However, compared with human insulin mixtures, twice-daily administration of insulin lispro mixtures resulted in improved postprandial glycemic control, similar overall glycemic control, and less nocturnal hypoglycemia, as well as offering the convenience of dosing closer to meals.

Nighttime Insulin Kinetics and Glycemic Control in Type 1 Diabetes Patients Following Administration of an Intermediate-Acting Lispro Preparation

OBJECTIVE To determine insulin kinetics and overnight glycemic control after bedtime administration of a new intermediate-acting insulin preparation called neutral protamine lispro (NPL). RESEARCH DESIGN AND METHODS We studied 12 patients with well-controlled type 1 diabetes. The study had a double-blind, randomized, crossover design. After a lead-in period of 10–14 days two experiments were carried out with an interval of 2–7 days. During these experiments overnight insulin kinetics and fasting blood glucose levels were studied after evening administration of NPH insulin and NPL. Blood glucose levels < 3.8 mmol/l were treated by means of a variable infusion of a 20% glucose solution. RESULTS A trend toward a shorter time to peak insulin concentration was observed after administration of NPL (P = 0.07). No differences between NPH and NPL were detected in the total area under the curve (AUC) for insulin, in insulin levels before breakfast, or in glucose levels before breakfast (P = 0.5, 0.6, and 0.4, respectively). CONCLUSIONS We detected no major differences between NPH and NPL in the total AUC for insulin, prebreakfast glucose levels, or prebreakfast insulin levels. Therefore, we conclude that NPH and NPL are equally effective in controlling overnight glycemia.

Glycemic control with Humalog® Mix25™ in type 2 diabetes inadequately controlled with glyburide

BACKGROUND Humalog Mix25 (Mix25) is a premixed insulin mixture of 25% insulin lispro and 75% neutral protamine lispro. OBJECTIVE The aim of this study was to quantitate the improvement in glycemic control achieved with Mix25 versus the maximum dose of glyburide (GB) in patients with type 2 diabetes inadequately controlled with GB. METHODS In this randomized, parallel, open-label comparative study, patients with type 2 diabetes received either Mix25 before the morning and evening meals for 4 months or GB 15 mg daily for 4 months. Glycemic control was assessed by glycosylated hemoglobin (HbA1c) measurements, 4-point self-monitored blood glucose profiles, and patient-reported hypoglycemia. Patients also completed a treatment satisfaction questionnaire at the end of the study. RESULTS All 172 patients were white; 85 were randomized to receive Mix25. The mean age was 59.5 +/- 8.2 years, and 35.5% (61/172) were men. The mean body mass index was 27.2 kg/m2. The mean duration of type 2 diabetes was 10.2 +/- 6.6 years, and the mean duration of sulfonylurea treatment was 5.8 +/- 5.9 years. The mean HbA1c and fasting blood glucose levels were 10.07% +/- 1.4% and 11.6 +/- 2.8 mmol/L, respectively, in the glyburide group and 9.85% +/- 1.2% and 12.2 +/- 2.9 mmol/L, respectively, in the Mix25 group. There were no statistically significant differences between the treatment groups at baseline for any of the demographic or efficacy variables. At end point, mean HbA1c was significantly lower in the Mix25 group than in the GB group (Mix25, 8.5% +/- 1.3%; GB, 9.4% +/- 1.8%; P = 0.001). A larger decrease from baseline in HbA1c and in all self-monitored blood glucose values was observed in the Mix25 group: -1.4% versus -0.7% for HbA1c, P = 0.004; -2.8 mmol/L versus -1.1 mmol/L for fasting blood glucose, P < 0.01; -5.1 mmol/L versus -1.7 mmol/L for the morning 2-hour postprandial blood glucose, P < 0.001; -2.2 mmol/L versus -0.8 mmol/L for the evening preprandial blood glucose, P < 0.05; and -4.4 mmol/L versus -1.5 mmol/L for the evening 2-hour postprandial blood glucose, P < 0.001. Patients expressed more satisfaction with Mix25 than with GB, as measured by the weighted combined score on a treatment satisfaction questionnaire (2.0 +/- 1.3 vs 0.7 +/- 1.3). The mean hypoglycemia rate (events per patient per 30 days) was significantly higher in the Mix25 group at end point (Mix25, 0.30 +/- 0.53; GB, 0.05 +/- 0.20; P < 0.001). CONCLUSIONS Compared with maximum-dose GB, twice-daily injections of Mix25 resulted in improved glycemic control and treatment satisfaction, and were associated with a predictably higher rate of hypoglycemia in this group of patients with type 2 diabetes who were inadequately controlled with maximum-dose GB. Although the inclusion of patients who were inadequately controlled with GB was intended to allow a comparison of the 2 treatments with respect to efficacy and tolerability in a real-life setting, a double-blind comparison in treatment-naive individuals may have resulted in a different outcome.

Effects of multiple daily injection therapy with Humalog mixtures versus separately injected insulin lispro and NPH insulin in adults with type I diabetes mellitus.

BACKGROUND Injection of insulin lispro (LP) before meals provides a more physiologic insulin activity profile than regular human insulin, but the relatively short duration of action of LP may allow the blood glucose (BG) level to increase during the late postprandial period (4-7 hours after meals) unless basal insulin is optimally replaced. One approach to basal insulin optimization has been to combine small doses of NPH with LP before meals. When used in a similar fashion, premixed, fixed-ratio insulin preparations containing LP and NPL (an LP-based intermediate-acting insulin) may provide the basis for an optimized basal-bolus insulin regimen. OBJECTIVE This study assessed mean late postprandial glycemic control during treatment with a premixed formulation consisting of a high proportion of LP (75% LP/25% NPL; H) and a premixed formulation consisting of a medium proportion of LP (50% LP/50% NPL; M). The H/M formulation was given before meals and was compared with treatment with preprandial LP + NPH (LP + N) in patients with type 1 diabetes mellitus (DM). METHODS This multicenter, randomized, open-label, 2-period crossover study was conducted at 4 centers in Italy and 1 center in France. Patients eligible for the study had type 1 DM, were > or = 18 years of age, and had a glycosylated hemoglobin (HbA(1c)) <150% of the upper limit of normal. Patients were randomly assigned to 1 of 2 treatment sequences: LP self-mixed with NPH before meals plus NPH alone at bedtime for 8 weeks (LP + N) followed by preprandial H or M, plus NPH alone at bedtime for 8 weeks (H/M), or the opposite sequence. Assessments included 8-point self-monitored BG profiles, HbA(1c), and hypoglycemia (any sign or symptom of hypoglycemia or BG < 3.0 mmol/L [<54.0 mg/dL]). The primary outcome measure was the late postprandial BG value, calculated as the mean of the combined prelunch (late postbreakfast), predinner (late postlunch), and bedtime (late postdinner) values. RESULTS A total of 89 patients with type 1 DM were enrolled (44 men, 45 women; mean [SD] age, 38.3 [12.8] years; mean [SD] body weight, 70.8 [11.6] kg; mean [SD] body mass index, 24.6 [3.0] kg/m(2); mean [SD] duration of diabetes, 17.8 [10.5] years; mean HbA(1c), 7.9% [0.88%]). The mean (SD) late postprandial BG values were similar between treatments (8.9 [2.1] mmol/L [160.3 (37.8) mg/dL] for H/M vs 9.0 [1.8] mmol/L [162.1 (32.4) mg/dL] for LP + N), as were the end point HbA(1c) values (7.8% [0.9%] for H/M vs 7.9% [0.8%] for LP + N). The rate of hypoglycemia was significantly higher during treatment with H/M, primarily because of episodes occurring between 12 PM and 6 PM, but was relatively low in both groups (mean/median rate per patient per 30 days: 2.87/2.14 for H/M and 2.11/1.07 for LP + N; P < 0.05). CONCLUSIONS In this population of patients with type 1 DM, preprandial H/M provided an effective alternative regimen for prandial and basal insulin replacement. Late postprandial BG control, an indicator of basal insulin sufficiency, was similar to that achieved with an intensified regimen of LP + N injected separately before meals, and the end point HbA(1c) was similar between the 2 treatments.

A note on the sample size determination in two-period repeated measurements crossover design with application to clinical trials

The two-period repeated measurements crossover design is often used in clinical trials. In this article we give a formula for sample size determination for testing treatment effect in two-period repeated measurements crossover design by taking an analysis of variance approach to the repeated measurements analysis. A balanced situation is considered: two treatment sequences that have the same number of patients, and the time points of measurements on each subject within each treatment period equal in number. The formula reveals the relationship between the required number of patients for each treatment sequence, the number of repeated measurements within each treatment period, the detectable treatment difference with respect to a primary response variable, and the power for testing the treatment difference. A clinical trial example is given to illustrate the use of the formula.