Long-term tolerability of inhaled human insulin (Exubera) in patients with poorly controlled type 2 diabetes

The Application of the Insulin to C-Peptide Molar Ratio (ICPR) in Primary Screening for Insulin Antibodies in Type 2 Diabetes Mellitus Patients: A Further Quantitative Study on the Relationship Between ICPR and Insulin Antibodies

Purpose

This study aimed to further quantify the relationship between insulin antibodies (IAs) and the 2-hour insulin to C-peptide molar ratio (2h-ICPR) using a multiple linear regression model in T2DM patients.

Methods

A total of 274 T2DM patients from April 2019 to December 2022 in Xiang'an Hospital of Xiamen University were included in this study. Multiple Linear Model Fitting was conducted on the candidate independent variables (age, BMI, HbA1c, and 2h-ICPR) for the multiple linear regression. The linear relationship between insulin antibodies (IAs) and the significant independent variables was presented by making multiple linear regression equations.

Results

The total demographic characteristics of the included patients were as follows: age (51.92±13.10 years), BMI (24.94±3.99 kg/m²), HbA1c (9.70±2.39%), 2h-ICPR (0.12±0.11), and IAs (0.37±1.12COI). Linear relationships of independent variables: age (r=0.163, p=0.007), 2h-ICPR (r=0.259, p=0.001), BMI (r=0.007, p=0.907) and 2h-ICPR (r=0.092, p=0.129). Multiple linear regression: age (unstandardized β=0.014, 95% CI: 0.004-0.024, p=0.004), 2h-ICPR (unstandardized β=2.758, 95% CI: 1.555-3.962, p≤0.001). The regression equation: .

Conclusion

The quantitative relationship between 2h-ICPR and insulin antibodies was . 2h-ICPR can be a preliminary screening indicator for insulin antibody testing in patients with type 2 diabetes.

Dry powder pharmaceutical biologics for inhalation therapy

Therapeutic biologics such as genes, peptides, proteins, virus and cells provide clinical benefits and are becoming increasingly important tools in respiratory medicine. Pulmonary delivery of therapeutic biologics enables the potential for safe and effective treatment option for respiratory diseases due to high bioavailability while minimizing absorption into the systemic circulation, reducing off-target toxicity to other organs. Development of inhalable powder formulation requires stabilization of complex biological materials, and each type of biologics may present unique challenges and require different formulation strategy combined with manufacture process to ensure biological and physical stabilities during production and over shelf-life. This review examines key formulation strategies for stabilizing proteins, nucleic acids, virus (bacteriophages) and bacterial cells in inhalable powders. It also covers characterization methods used to assess physicochemical properties and aerosol performance of the powders, biological activity and structural integrity of the biologics, and chemical analysis at the nanoscale. Furthermore, the review includes manufacture technologies which are based on lyophilization and spray-drying as they have been applied to manufacture Food and Drug Administration (FDA)-approved protein powders. In perspective, formulation and manufacture of inhalable powders for biologic are highly challenging but attainable. The key requirements are the stability of both the biologics and the powder, along with the powder dispersibility. The formulation to be developed depends on the manufacture process as it will subject the biologics to different stresses (temperature, mechanical and chemical) which could lead to degradation by different pathways. Stabilizing excipients coupled with the suitable choice of process can alleviate the stability issues of inhaled powders of biologics.

Can inhaled insulin be used for the treatment of diabetes mellitus?

Reluctance to start and adequately titrate subcutaneous insulin are major reasons why many patients with diabetes mellitus are insufficiently metabolically controlled. Pulmonary insulin administration has the advantage over subcutaneous insulin in that it is noninvasive, seems better accepted by the diabetic population and exerts equal efficacy in terms of glycemic control. As such, inhaled insulin has the potential to increase the diabetic (Type 2) patient's willingness to commence and adhere to insulin therapy. Inhaled insulin's short duration of action makes it suitable for prandial administration provided that basal insulin requirements are met by residual b-cell function, or by supplemental long-acting subcutaneous insulin. In clinical trials, inhaled insulin is comparable to short-acting subcutaneous insulin with regard to efficacy and hypoglycemic risk. Adverse effects associated with inhaled insulin include dry cough, which tends to diminish over time, a slight drop in pulmonary function that does not progress and is reversible in most patients if treatment is discontinued, and increased insulin antibody formation, albeit without clinical sequelae. Long-term safety remains an issue for a product intended to be used chronically for many years. Exubera((R)) was thus far the only inhaled insulin product to receive approval in the USA and Europe for use in adults with Type 1 or Type 2 diabetes, but was recently withdrawn from the market. At present it is unclear how this decision will affect programs from other companies with inhaled insulin products under development.

Inhaled insulin forms toxic pulmonary amyloid aggregates

It is well known that interfaces, such as polar-nonpolar or liquid-air, play a key role in triggering protein aggregation in vitro, in particular the aggregation of peptides and proteins with the predisposition of misfolding and aggregation. Here we show that the interface present in the lungs predisposes the lungs to form aggregation of inhaled insulin. Insulin inhalers were introduced, and a large number of diabetic patients have used them. Although inhalers were safe and effective, decreases in pulmonary capacity have been reported in response to inhaled insulin. We hypothesize that the lung air-tissue interface provides a template for the aggregation of inhaled insulin. Our studies were designed to investigate the harmful potential that inhaled insulin has in pulmonary tissue in vivo, through an amyloid formation mechanism. Our data demonstrate that inhaled insulin rapidly forms amyloid in the lungs causing a significant reduction in pulmonary air flow. Our studies exemplify the importance that interfaces play in protein aggregation in vivo, illustrating the potential aggregation of inhaled proteins and the formation of amyloid deposits in the lungs. These insulin deposits resemble the amyloid structures implicated in protein misfolding disorders, such as Alzheimer's and Parkinson's diseases, and could as well be deleterious in nature.

Inhaled insulin: overview of a novel route of insulin administration

Diabetes is a chronic disease characterized by inadequate insulin secretion with resulting hyperglycemia. Diabetes complications include both microvascular and macrovascular disease, both of which are affected by optimal diabetes control. Many individuals with diabetes rely on subcutaneous insulin administration by injection or continuous infusion to control glucose levels. Novel routes of insulin administration are an area of interest in the diabetes field, given that insulin injection therapy is burdensome for many patients. This review will discuss pulmonary delivery of insulin via inhalation. The safety of inhaled insulin as well as the efficacy in comparison to subcutaneous insulin in the various populations with diabetes are covered. In addition, the experience and pitfalls that face the development and marketing of inhaled insulin are discussed.

Glycemic control with preprandial versus basal insulin in patients with type 2 diabetes mellitus poorly controlled by oral antidiabetes agents

OBJECTIVE

This study was designed to compare glycemic control (glycated hemoglobin [A1C] level) with either once-daily basal insulin (BI) (insulin glargine) or preprandial insulin (PPI) (Exubera) [insulin human (recombinant DNA origin)] inhalation powder, Pfizer Inc., New York, NY) in patients with type 2 diabetes mellitus (T2DM) poorly controlled on at least two oral antidiabetes agents (OADs).

METHODS

This was a 26-week, open-label, parallel-group, randomized study where 257 patients (mean A1C 8.6%) on OAD treatment for > or = 3 months were treated with either BI (n = 122) or PPI (n = 135). Based on self-monitored blood glucose levels, PPI dose was adjusted before each major meal, whereas BI dose was titrated in the morning or before bedtime. Prestudy OADs were continued, but doses could be modified.

RESULTS

At 26 weeks, change from baseline in A1C was greater with PPI (-1.7 vs. -1.4%, P = 0.0389). Numerically, more patients achieved A1C <6.5% (28% vs. 19%) and A1C <7.0% (63% vs. 55%) with PPI compared with BI. PPI had lower postmeal glucose increments, but higher prebreakfast glucose and weight gain (1.1kg), than BI. Mild or moderate hypoglycemic events were more frequent with PPI (6.2 vs. 2.9 events/months), but nocturnal hypoglycemic events were less frequent (22% vs. 30%).

CONCLUSIONS

PPI improved postprandial glucose and A1C levels significantly more than BI. More patients achieved A1C targets with PPI, at the expense of more hypoglycemia and body weight gain. These results illustrate the potential benefits and detriments of prandial insulin supplementation in patients with T2DM poorly controlled on OADs alone.

Safety and efficacy of inhaled human insulin (exubera) during discontinuation and readministration of therapy in adults with type 2 diabetes: a 3-year randomized controlled trial

OBJECTIVE

This study assessed pulmonary safety following discontinuation and readministration of inhaled human insulin {Exubera [EXU] [Pfizer Inc., New York, NY] (insulin human [recombinant DNA origin]) inhalation powder} in adults with type 2 diabetes (T2DM).

METHODS

Patients were randomized to receive EXU (n = 316) or subcutaneous (SC) insulin (n = 311) for 2 years (comparative phase), followed by 6 months of SC insulin (washout phase) and 6 months of original therapy (readministration). Highly standardized lung function tests were performed throughout all phases.

RESULTS

Small, nonprogressive treatment group differences were observed to occur early during the comparative phase for parameters such as change from baseline for forced expiratory volume in 1 s (FEV(1)) and carbon monoxide diffusing capacity (DL(CO)). These differences resolved during washout and recurred to the same small magnitude during readministration. Both treatment groups maintained similar glycemic control and hypoglycemic event rates. In the EXU group, insulin antibody (IAb) levels reached a plateau at 9 months, declined to near baseline levels during washout, and increased during readministration to levels observed in the comparative phase.

CONCLUSIONS

FEV(1) and DL(CO) changes observed during discontinuation and readministration of EXU therapy were consistent with a reversible, nonprogressive, and nonstructural pathologic effect on lung function in adults with T2DM. EXU readministration was not associated with an augmented IAb response.

Effect of insulin on airway responsiveness in patients with type 2 diabetes mellitus: a cohort study

BACKGROUND

The correlation between low insulin levels and a decreased sensitivity of the muscarinic receptor has been shown on induced-diabetes animal models. We designed a cohort study with the aim of evaluating the effects of insulin therapy on airway responsiveness (AR) in human patients with type 2 diabetes mellitus.

METHODS

We enrolled 92 patients with type 2 diabetes who had switched from oral anti-diabetic therapy to treatment by insulin subcutaneous injection. Patients were administered the methacholine challenge test (MCT) at time 0 (pre-insulin therapy) and at intervals of 15, 30, 90, 180, and 360 days after insulin treatment. The decline of forced expiratory volume in 1 second (FEV(1))% from baseline (Delta FEV(1)) in response to inhaled methacholine (MCH) was determined to assess airway hyper-responsiveness (AHR).

RESULTS

A total of 81 patients (18 women and 63 men) completed the study. Their mean age was 58 +/- 7 years and the mean duration of disease was 13.5 +/- 7.7 years. The mean decrease of FEV(1) at pre-insulin assessment was 2.96 +/- 2.6%. Compared with the pre-insulin value, a significant increase of Delta FEV(1) was observed at 15, 30, and 90 days after treatment (6.25%, CI 95% 5.4 to 7.2, p = 0.0005; 7.64%, CI 95% 6.6 to 8.1, p < 0.001; 6.45%, CI 95% 5.5 to 7.3, p = 0.0004, respectively), while after 180 and 360 days AR was similar to pre-insulin values (Delta FEV(1), 3.62%, CI 95% 2.7 to 3.5 and 3.11%, CI 95% 7.9 to 9.3, respectively).

CONCLUSIONS

The finding of an increased AR in patients with type 2 diabetes during the first 3 months of insulin therapy may underline the importance of monitoring pulmonary function and respiratory symptoms in patients switching from oral anti-diabetic drugs to insulin therapy, especially in the subset of individuals with respiratory disorders.

Intraoperative glycemic control procedures and the use of an artificial pancreas

Strict intraoperative glycemic control can significantly decrease the incidence of postoperative infection; however, anesthesiologists must carefully control blood glucose levels as well as properly manage the respiratory and cardiovascular systems. However, standard blood glucose measurement systems and insulin dosing algorithms, which are necessary for achieving strict glycemic control, have not yet been developed. An artificial pancreas (STG-22^TM; Nikkiso Co., Tokyo, Japan) is considered a highly accurate blood glucose monitoring system capable of closed-loop control of blood glucose. The device has, however, many problems to be addressed since it is a large and expensive system with little versatility, and it requires a large amount of blood to be collected. Therefore, the development of less invasive and inexpensive systems with future technological progress is greatly anticipated.

Two-year efficacy and safety of AIR inhaled insulin in patients with type 1 diabetes: An open-label randomized controlled trial

BACKGROUND

Patients with type 1 diabetes require intensive insulin therapy for optimal glycemic control. AIR((R)) inhaled insulin (system from Eli Lilly and Company, Indianapolis, IN) (AIR is a registered trademark of Alkermes, Inc., Cambridge, MA) may be an efficacious and safe alternative to subcutaneously injected (SC) mealtime insulin.

METHODS

This was a Phase 3, 2-year, randomized, open-label, active-comparator, parallel-group study in 385 patients with type 1 diabetes who were randomly assigned to receive AIR insulin or SC insulin (regular human insulin or insulin lispro) at mealtimes. Both groups received insulin glargine once daily. Efficacy measures included mean change in hemoglobin A1C (A1C) from baseline to end point, eight-point self-monitored blood glucose profiles, and insulin dosage. Safety assessments included hypoglycemic events, pulmonary function tests, adverse events, and insulin antibody levels.

RESULTS

In both treatment groups, only 20% of subjects reached the target of A1C <7.0%. A significant A1C difference of 0.44% was seen favoring SC insulin, with no difference between the groups in insulin doses or hypoglycemic events at end point. Patients in both treatment groups experienced progressive decreases in lung function, but larger (reversible) decrements in diffusing capacity of the lung for carbon monoxide (DL(CO)) were associated with AIR insulin treatment. Greater weight gain was seen with SC insulin treatment.

CONCLUSIONS

The AIR inhaled insulin program was terminated by the sponsor prior to availability of any Phase 3 data for reasons unrelated to safety or efficacy. Despite early termination, this trial provides evidence that AIR insulin was less efficacious in lowering A1C and was associated with a greater decrease in DL(CO) and increased incidence of cough than SC insulin in patients with type 1 diabetes.

Safety and efficacy of AIR inhaled insulin compared with subcutaneous insulin in patients having diabetes and asthma: A 12-month, randomized, noninferiority trial

BACKGROUND

Long-term safety and efficacy of AIR((R)) inhaled insulin (Eli Lilly and Co., Indianapolis, IN) (AIR is a registered trademark of Alkermes, Inc., Cambridge, MA) in patients with diabetes and concomitant lung disease remain to be established.

METHODS

This 1-year, randomized, open-label, active comparator, two-arm, parallel study compared the safety and efficacy of AIR insulin to subcutaneous (SC) insulin in patients having type 1 or type 2 diabetes and asthma. Patients with type 2 diabetes continued taking their prestudy oral antihyperglycemic medication.

RESULTS

Change in hemoglobin A1C from baseline to end point was similar for the AIR insulin and SC insulin groups (-0.063 +/- 0.128% and -0.315 +/- 0.128% respectively, P = 0.105), but noninferiority failed to be achieved (the upper limit of the 95% confidence interval [-0.053, 0.555] was >0.4%). The total daily prandial dose increased more in the AIR insulin group than in the SC insulin group (0.150 U/kg and 0.044 U/kg, respectively, P = 0.002). Safety profiles were generally comparable between treatments. At end point, forced expiratory volume in 1 s (FEV(1))/forced vital capacity (FVC) postbronchodilator (-0.016 +/- 0.005 vs. 0.002 +/- 0.005, P = 0.006) and diffusing capacity of the lung for carbon monoxide (-1.214 +/- 0.325 mL/min/torr vs. -0.383 +/- 0.311 mL/min/torr, P = 0.028) both decreased more in the AIR insulin group than in the SC insulin group, but the differences were not present at follow-up. FEV(1) and FVC were similar between treatment groups at end point. Incidences of hypoglycemia were comparable between groups. Insulin antibody binding increased more in the AIR insulin group. Cough was the most common adverse event; however, there was no difference in incidence between the AIR insulin (15.3%) and SC insulin (12.4%) treatment groups (P = 0.572).

CONCLUSIONS

In patients who have diabetes and asthma, AIR insulin demonstrated glycemic efficacy similar to SC insulin. Additionally, the safety profile of AIR insulin in patients with and without asthma is consistent.

Safety and efficacy of inhaled insulin (AERx iDMS) compared with subcutaneous insulin therapy in patients with Type 1 diabetes: 1-year data from a randomized, parallel group trial

AIMS

Assessment of the long-term safety and efficacy of liquid inhaled insulin via AERx insulin Diabetes Management System (iDMS) in a basal/bolus treatment regimen of adults with Type 1 diabetes.

METHODS

Patients were randomized 2 : 1 to prandial inhaled (n = 205) or subcutaneous (s.c.) (n = 99) insulin, plus one/two daily injections of neutral protamine Hagedorn (NPH) insulin for 12 months. The primary endpoints were pulmonary function tests (PFT) and baseline changes in chest X-rays at 12 months. Safety and efficacy assessments were measured at regular intervals.

RESULTS

PFTs after 12 months were comparable between the groups, except for reduced per cent of predicted carbon monoxide lung diffusing capacity with inhaled insulin (difference: -2.03%, P = 0.04) occurring after the first 3 months and then stabilizing. There were no apparent treatment differences in chest X-rays. Overall risk of hypoglycaemia [risk ratio (RR) 1.02, P = 0.83] and adverse events were comparable between groups. Risk of nocturnal hypoglycaemia was higher in the inhaled group (RR 1.58, P = 0.001). Cough [10% (inhaled); 3% (s.c.)] tended to be mild in nature. Inhaled insulin was non-inferior to s.c. insulin for change in glycated haemoglobin (HbA(1c)) after 12 months [difference 0.18% (CI 95%-0.04; 0.39)]. At trial end, mean laboratory measured fasting plasma glucose was lower in the inhaled group (inhaled 9.2 mmol/l; s.c. 11.7 mmol/l; difference: -2.53 mmol/l, P < 0.001).

CONCLUSIONS

The safety and efficacy results in this trial were similar to those reported with other inhaled insulins; however, inhaled insulin using AERx iDMS requires further optimization to reduce nocturnal hypoglycaemia before it has comparable safety and efficacy to s.c. insulin aspart.

Assessment of long-term immunological and pulmonary safety of inhaled human insulin with up to 24 months of continuous therapy

BACKGROUND

This study was performed to characterize the long-term safety and efficacy of inhaled human insulin (EXU; Exubera * (insulin human [rDNA origin]) Inhalation Powder). * Pfizer Inc, New York, NY, USA.

SCOPE

Patients with type 1 or type 2 diabetes (N = 1290) who had successfully completed one of six controlled EXU open-label trials elected to receive open-label treatment with EXU for up to 3 years, after which they were randomized to discontinue EXU or to continue therapy for 6 months, then discontinue. Immunologic safety was assessed by insulin antibody (IAb) binding, and pulmonary safety was assessed by tests for forced expiratory volume in 1 second (FEV(1)) and carbon monoxide diffusing capacity (DL(CO)). In addition, changes over time in IAbs were compared with changes in FEV(1), DL(CO), hypoglycemia, and efficacy.

FINDINGS

Antibody binding increased in patients with either type 1 or type 2 diabetes after initiation of EXU and plateaued within 6-12 months (increases were higher in patients with type 1 diabetes than in patients with type 2 diabetes). Decreases in FEV(1) occurred primarily during the first 3-6 months of EXU therapy. Among adult patients in the All Subjects set, the mean (± SE) annualized rate of decline in FEV(1) was -0.053 ± 0.007 liters/year (95% CI, -0.065, -0.040) in adult patients with type 1 diabetes, and -0.076 ± 0.005 liters/year (95% CI, -0.085, -0.067) in patients with type 2 diabetes. Changes in DL(CO) occurred primarily during the first 3-6 months of EXU therapy. Among adult patients, in the All Subjects set, the mean (± SE) annual decline in DL(CO) was -0.738 ± 0.097 mL/min/mmHg/year (95% CI, -0.927, -0.548) and -0.688 ± 0.082 mL/min/mmHg/year (95% CI, -0.849, -0.527) in patients with type 1 and type 2 diabetes, respectively. Antibody binding did not correlate with changes in glycemic control, lung function, dose, or hypoglycemia. Following discontinuation of EXU, IAbs decreased to near baseline levels.

CONCLUSION

These results are consistent with other trials showing long-term maintenance of safety and efficacy of EXU despite insulin antibody formation and small treatment group differences in pulmonary function. A limitation of the study was the lack of a comparator therapy.

Two-year pulmonary safety and efficacy of inhaled human insulin (Exubera) in adult patients with type 2 diabetes

OBJECTIVE

The purpose of this study was to evaluate the 2-year pulmonary safety of inhaled human insulin (Exubera [EXU]) in 635 nonsmoking adults with type 2 diabetes.

RESEARCH DESIGN AND METHODS

Patients were randomly assigned to receive prandial EXU or subcutaneous insulin (regular or short-acting) plus basal (intermediate- or long-acting) insulin. The primary end points were the annual rate of decline in forced expiratory volume in 1 s (FEV(1)) and carbon monoxide diffusing capacity (DL(CO)).

RESULTS

Small differences in FEV(1) favoring subcutaneous insulin developed during the first 3 months but did not progress. Adjusted treatment group differences in FEV(1) annual rate of change were -0.007 l/year (90% CI -0.021 to 0.006) between months 0 and 24 and 0.000 l/year (-0.016 to 0.016) during months 3-24. Treatment group differences in DL(CO) annual rate of change were not significant. Both groups sustained similar reductions in A1C by month 24 (last observation carried forward) (EXU 7.7-7.3% vs. subcutaneous insulin 7.8-7.3%). Reductions in fasting plasma glucose (FPG) were greater with EXU than with subcutaneous insulin (adjusted mean treatment difference -12.4 mg/dl [90% CI -19.7 to -5.0]). Incidence of hypoglycemia was comparable in both groups. Weight increased less with EXU than with subcutaneous insulin (-1.3 kg [-1.9 to -0.7]). Adverse events were comparable, except for a higher incidence of mild cough and dyspnea with EXU.

CONCLUSIONS

Two-year prandial EXU therapy showed a small nonprogressive difference in FEV(1) and comparable sustained A1C improvement but lower FPG levels and less weight gain than seen in association with subcutaneous insulin in adults with type 2 diabetes.

Acute passive cigarette smoke exposure and inhaled human insulin (Exubera) pharmacokinetics

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

Active cigarette smoking is associated with increased permeability of the pulmonary alveolar epithelium, resulting in faster absorption of inhaled drugs such as Exubera (EXU). Absorption of EXU is increased approximately twice to four times as much in chronic smokers compared with nonsmokers. The rate of clearance of radioaerosols such as technetium-labelled diethylenetriamine penta-acetic acid is decreased in response to passive smoke exposure.

WHAT THIS STUDY ADDS

Passive smoke exposure causes a decrease in lung permeability, an effect opposite to that of active smoking. Acute passive smoke exposure results in a decrease in EXU bioavailability and does not create a risk of hypoglycaemia. These results are consistent with previous studies of radioaerosol lung clearance. AIMS Relative to nonsmokers, the bioavailability of inhaled human insulin (Exubera(R); EXU) is markedly increased in chronic smokers. The pharmacokinetics of EXU following passive cigarette smoke exposure is unknown. METHODS In an open-label, crossover study, healthy nonsmoking volunteers received two treatments in randomized sequence separated by a 2-week wash-out: (i) EXU 3 mg with no passive smoke exposure and (ii) EXU 3 mg after passive smoke exposure (atmospheric nicotine levels 75-125 mug m(-3)) for 2 h. Blood samples were obtained at prespecified times up to 6 h after EXU administration.

RESULTS

Twenty-seven subjects completed both study periods. Mean plasma insulin AUC(0-360) decreased by 17% [ratio 83%, 95% confidence interval (CI) 68.8, 99.5] and mean C(max) by 29% (ratio 71%, 95% CI 59.8, 83.1) after passive cigarette smoke exposure. The median (range) t(max) was 60 min (20-120 min) and 75 min (20-360 min) in the EXU with no exposure and EXU passive exposure groups, respectively. EXU was well tolerated.

CONCLUSIONS

Unlike active chronic smoking, acute passive cigarette smoke exposure modestly decreases EXU bioavailability and thus should not increase hypoglycaemia risk. These results are consistent with those from published literature involving technetium-labelled diethylenetriamine penta-acetic acid and suggest that passive cigarette smoke exposure causes an acute decrease in lung permeability vs. active smoking, which causes an increase in permeability.