Pharmacokinetics and linear exposure of AFRESA compared with the subcutaneous injection of regular human insulin

Emerging Diabetes Technologies: Continuous Glucose Monitors/Artificial Pancreases

Over the past decade there have been many advances in diabetes technologies, such as continuous glucose monitors (CGM s), insulin-delivery devices, and hybrid closed loop systems . Now most CGMs (Medtronic-Guardian, Dexcom-G6, and Abbott-Libre-2) have MARD values of < 10%, in contrast to two decades ago when the MARD used to be > 20%. In addition, the majority of the new CGMs do not require calibrations, and the latest CGMs last for 10-14 days. An implantable 6-months CGM by Eversense-3 is now approved in the USA and Europe. Recently, the FDA approved Libre 3 which provides real-time glucose values every minute. Even though it is approved as an iCGM it is not interoperable with automatic-insulin-delivery (AID) systems. The newer CGMs that are likely to be launched in the next few months in the USA include the 10-11 days Dexcom G7 (60% smaller than the existing G6), and the 7-days Medtronic Guardian 4. Most of the newer CGM have several features like automatic initialization, easy insertion, predictive alarms, and alerts. It has also been noticed that an arm insertion site might have better accuracy than abdomen or other sites, like the buttock for kids. Lag time between YSI and different sensors have been reported differently, sometimes it is down to 2-3 min; however, in many instances, it is still 15-20 min, especially when the rate of change of glucose is > 2 mg/min. We believe that in the next decade there will be a significant increase in the number of people who use CGM for their day-to-day diabetes care.

Insulin Therapy in Small Animals, Part 1: General Principles

Understanding the pharmacology of insulin and how it relates to the pathophysiology of diabetes can lead to better clinical outcomes. No insulin formulation should be considered "best" by default. Insulin suspensions (NPH, NPH/regular mixes, lente, and PZI) as well as insulin glargine U100 and detemir are intermediate-acting formulations that are administered twice daily. For a formulation to be an effective and safe basal insulin, its action should be roughly the same every hour of the day. Currently, only insulin glargine U300 and insulin degludec meet this standard in dogs, whereas in cats, insulin glargine U300 is the closest option.

Arginine-Coated Nanoglobules for the Nasal Delivery of Insulin

Multiple daily injections via subcutaneous route are the primary modes of insulin delivery for patients with Diabetes Mellitus. While this process is invasive, painful and may cause patients to develop lipohypertrophy at injection site, the perception of fear surrounding this process causes patients to delay in initiation and remain persistent with insulin therapy over time. Moreover, poor glycemic control may often lead to acute complications, such as severe hypoglycemia and nocturnal hypoglycemia, especially in older patients with diabetes. To address the imperative need for a patient-convenient non-invasive insulin therapy, an insulin-loaded arginine-coated self-emulsifying nanoglobule system (INS-LANano) was developed for nasal delivery of insulin with a biodegradable cationic surfactant-Lauroyl Ethyl Arginate (LAE). Incorporation of LAE resulted in formation of positively charged nanoglobules with L-arginine oriented on the surface. LANano enabled binding of insulin molecules on the surface of nanoglobules via an electrostatic interaction between negatively charged α-helix and LAE molecules at physiological pH. INS-LANano showed a hydrodynamic diameter of 23.38 nm with a surface charge of +0.118 mV. The binding efficiency of insulin on LANano globules was confirmed by zeta potential, circular dichroism (CD) spectroscopy and centrifugal ultrafiltration studies. The attachment of insulin with permeation-enhancing nanoglobules demonstrated significantly higher in vitro permeability of insulin of 15.2% compared to insulin solution across human airway epithelial cell (Calu-3) monolayer. Upon intranasal administration of INS-LANano to diabetic rats at 2 IU/kg insulin dose, a rapid absorption of insulin with significantly higher Cmax of 14.3 mU/L and relative bioavailability (BA) of 23.3% was observed. Therefore, the INS-LANano formulation significant translational potential for intranasal delivery of insulin.

One hundred years of insulin: Is it time for smart?

Smarter understanding of diabetes pathophysiology and pharmacology of insulin therapy can lead to better clinical outcomes. Rather than looking for an insulin formulation that is considered "best" for a general population, it could be appropriate to seek the "smart" insulin choice, tailored to the specific clinical situation. Different treatment goals should be considered, with pros and cons to each. Ideally, insulin therapy in most diabetic dogs should mimic a "basal-bolus" pattern. The "intermediate"-acting insulin formulations might provide better "bolus" treatment in dogs than the rapid-acting formulations used in people. In patients with some residual beta cell function such as many diabetic cats, administering only a "basal" insulin might lead to complete normalisation of blood glucose concentrations. Insulin suspensions (neutral protamine Hagedorn, neutral protamine Hagedorn/regular mixes, lente and protamine zinc insulin) as well as insulin glargine U100 and detemir are "intermediate"-acting formulations that are administered twice daily. For a formulation to be an effective and safe "basal" insulin, its action should be roughly the same every hour of the day. Currently, only insulin glargine U300 and insulin degludec meet this standard in dogs, whereas in cats, insulin glargine U300 is the closest option.

Comparative Analysis of Inhaled Insulin With Other Types in Type 1 Diabetes Mellitus: A Systematic Review and Meta-Analysis

To analyze the effect of Inhaled insulin in Type 1 Diabetes Mellitus and compare it with other routes of administration of Insulin. A systemic search was conducted from the following electronic databases: PubMed/Medline, Cochrane Library, and Google Scholar, from inception to 28th January 2022. All statistical analysis was conducted in Review Manager 5.4.1. All studies meeting inclusion criteria were selected. A random-effect model was used to pool the studies, and the result was reported in the Standard Mean Difference (SMD), Mean Difference (MD), and Risk Ratio (RR) with their corresponding 95% Confidence interval (CI). Thirteen randomized control trials were selected for our meta-analysis. Statistically significant results were obtained for comparing change in weight after insulin administration (MD= -1.08 [-1.21, -0.94]; p< 0.00001; I2= 74%). Other factors assessed were found to be non-significant like HbA1c (SMD= 0.03 [-0.80, 0.86]; p= 0.95; I2= 99%), fasting blood sugar (SMD= -0.31 [-1.52, 0.91]; p= 0.62; I2= 99%) and adverse effects (RR= 1.06 [0.97, 1.16]; p= 0.18; I2= 96%). In this systematic review and meta-analysis, we found that inhaled insulin is equally effective as subcutaneously administered insulin in patients with Type 1 Diabetes. The inhaled insulin was found to show less weight gain and fewer hypoglycemic shifts, with a similar effect on the blood glucose level. No significant difference was observed in the incidence of adverse events.

Long-Term Nonclinical Pulmonary Safety Assessment of Afrezza, a Novel Insulin Inhalation Powder

Afrezza delivers inhaled insulin using the Gen2 inhaler for the treatment of patients with type 1 and type 2 Diabetes. Afrezza was evaluated in long-term nonclinical pulmonary safety studies in 2 toxicology species. Chronic inhalation toxicology studies in rat (26 weeks) and dog (39 weeks) and an inhalation carcinogenicity study in rats were conducted with Technosphere insulin (Afrezza) and with Technosphere alone as a vehicle control. Respiratory tract tissues were evaluated by histopathology and cells expressing proliferating cell nuclear antigen (PCNA) were quantified in lungs of rats. Microscopic findings in rats exposed to Afrezza were attributed to the Technosphere particle component, were confined to nasal epithelia, and consisted of eosinophilic globules and nasal epithelial degeneration. There were no Afrezza-related changes in pulmonary PCNA labeling indices in alveoli, large bronchioles, or terminal bronchioles. Microscopic findings in rats exposed to Technosphere particles included eosinophilic globules, mucus cell hyperplasia, and epithelial degeneration in the nasal cavities. PCNA labeling indices were increased in large bronchioles and terminal bronchioles but not in alveoli. There were no Technosphere particle-related findings in the dog study. Afrezza did not exhibit carcinogenic potential in the 2-year study in rats. These nonclinical inhalation studies support the use of Afrezza in humans over extended periods.

Recent Avenues in Novel Patient-Friendly Techniques for the Treatment of Diabetes

Background:

Diabetes is one of the most common chronic metabolic disorders which affect the quality of human life worldwide. As per the WHO report, between 1980 to 2014, the number of diabetes patients increases from 108 million to 422 million, with a global prevalence rate of 8.5% per year. Diabetes is the prime reason behind various other diseases like kidney failure, stroke, heart disorders, glaucoma, etc. It is recognized as the seventh leading cause of death throughout the world. The available therapies are painful (insulin injections) and inconvenient due to higher dosing frequency. Thus, to find out a promising and convenient treatment, extensive investigations are carried out globally by combining novel carrier system (like microparticle, microneedle, nanocarrier, microbeads etc.) and delivery devices (insulin pump, stimuli-responsive device, inhalation system, bioadhesive patch, insulin pen etc.) for more precise diagnosis and painless or less invasive treatment of disease.

Objective:

The review article is made with an objective to compile information about various upcoming and existing modern technologies developed to provide greater patient compliance and reduce the undesirable side effect of the drug. These devices evade the necessity of daily insulin injection and offer a rapid onset of action, which sustained for a prolonged duration of time to achieve a better therapeutic effect.

Conclusion:

Despite numerous advantages, various commercialized approaches, like Afrezza (inhalation insulin) have been a failure in recent years. Such results call for more potential work to develop a promising system. The novel approaches range from the delivery of non-insulin blood glucose lowering agents to insulin-based therapy with minimal invasion are highly desirable.

Pharmacokinetic and Pharmacodynamic Properties of a Novel Inhaled Insulin

Advances in insulin treatment options over recent decades have markedly improved the management of diabetes. Despite this, glycemic control remains suboptimal in many people with diabetes. Although postprandial glucose control has been improved with the development of subcutaneously injected rapid-acting insulin analogs, currently available insulins are not able to fully mimic the physiological time-action profile of endogenously secreted insulin after a meal. The delayed onset of metabolic action and prolonged period of effect induce the risk of postprandial hyperglycemia and late postprandial hypoglycemia. A number of alternative routes of insulin administration have been investigated over time in an attempt to overcome the limitations associated with subcutaneous administration and to provide an improved time-action insulin profile more closely simulating physiological prandial insulin release. Among these, pulmonary insulin delivery has shown the most promise. Technosphere® Inhaled Insulin (TI) is a rapid-acting inhaled human insulin recently approved by the FDA for prandial insulin therapy. In this article we discuss the pharmacokinetic and pharmacodynamic properties of TI, and, based on key studies performed during its clinical development, the implications for improved postprandial glucose control.

Place of technosphere inhaled insulin in treatment of diabetes

Technosphere insulin (TI), Afrezza, is a powder form of short-acting regular insulin taken by oral inhalation with meals. Action of TI peaks after approximately 40-60 min and lasts for 2-3 h. TI is slightly less effective than subcutaneous insulin aspart, with mean hemoglobin A1c (HbA1c) reduction of 0.21% and 0.4%, respectively. When compared with technosphere inhaled placebo, the decrease in HbA1c levels was 0.8% and 0.4% with TI and placebo, respectively. Compared with insulin aspart, TI is associated with lower risk of late post-prandial hypoglycemia and weight gain. Apart from hypoglycemia, cough is the most common adverse effect of TI reported by 24%-33% of patients vs 2% with insulin aspart. TI is contraindicated in patients with asthma and chronic obstructive pulmonary disease. While TI is an attractive option of prandial insulin, its use is limited by frequent occurrence of cough, need for periodic monitoring of pulmonary function, and lack of long-term safety data. Candidates for use of TI are patients having frequent hypoglycemia while using short-acting subcutaneous insulin, particularly late post-prandial hypoglycemia, patients with needle phobia, and those who cannot tolerate subcutaneous insulin due to skin reactions.

[Fast-acting insulin - new developments towards more flexibility for the patient]

BACKGROUND

Post-prandial insulin secretion occurs under physiological conditions very fast and in adequate concentrations. This mechanism is impaired in patients with type 2 diabetes and severe increases of postprandial glucose levels may occur. In order to achieve physiological conditions and to avoid postprandial hyperglycemia, exogenous insulin and insulin analogues should be absorbed very fast and appropriate maximum concentrations should be reached very quickly.

METHOD

Overview RESULTS AND CONCLUSIONS: The development of new bolus insulins is focused on improved pharmacokinetic and pharmacodynamic properties. Not only new pharmaceutical formulations, but also different application sites and systems have been investigated. The latest innovations resulted in even faster acting insulins, which may offer patients improved postprandial glucose control and greater flexibility regarding meal planning.

Pharmacological and toxicological assessment of innovative self-assembled polymeric micelles as powders for insulin pulmonary delivery

Aim: Explore the use of polymeric micelles in the development of powders intended for pulmonary delivery of biopharmaceuticals, using insulin as a model protein. Materials & methods: Formulations were assessed in vitro for aerosolization properties and in vivo for efficacy and safety using a streptozotocin-induced diabetic rat model. Results: Powders presented good aerosolization properties like fine particle fraction superior to 40% and a mass median aerodynamic diameter inferior of 6 μm. Endotracheally instilled powders have shown a faster onset of action than subcutaneous administration of insulin at a dose of 10 IU/kg, with pharmacological availabilities up to 32.5% of those achieved by subcutaneous route. Additionally, micelles improved the hypoglycemic effect of insulin. Bronchoalveolar lavage screening for toxicity markers (e.g., lactate dehydrogenase, cytokines) revealed no signs of lung inflammation and cytotoxicity 14 days postadministration. Conclusion: Developed powders showed promising safety and efficacy characteristics for the systemic delivery of insulin by pulmonary administration.

AFREZZA® (insulin human) Inhalation Powder: A Review in Diabetes Mellitus

Afrezza® (insulin human) inhalation powder is a rapid-acting Technosphere® insulin (TI) administered via a breath-powered oral inhaler to patients with diabetes requiring prandial insulin. TI, a dry powdered formulation of recombinant human insulin adsorbed onto a proprietary carrier, is designed to deliver insulin to the deep lung, at the level of the alveoli, where it is absorbed into the systemic circulation. In a randomized, open-label, multinational, phase III trial (trial 171) in type 1 diabetes (T1DM) patients, prandial TI via the Gen2 inhaler provided noninferior glycated haemoglobin (HbA1c) lowering compared with prandial subcutaneous insulin aspart. Although TI was associated with less HbA1c lowering, it provided significantly lower fasting plasma glucose levels and significantly less hypoglycaemia and bodyweight gain compared with insulin aspart. In a randomized, double-blind, placebo-controlled, multinational, phase III trial (trial 175) in type 2 diabetes (T2DM) patients, prandial TI via the Gen2 inhaler provided superior HbA1c lowering compared with inhaled placebo. Cough was the most commonly occurring non-hypoglycaemia adverse event across both studies. In a pooled analysis of tolerability data from phase II and III studies, the most commonly occurring non-hypoglycaemia adverse events in T1DM and T2DM patients were cough and throat pain/irritation. However, cough was generally mild, dry and decreased over time. In addition, treatment with TI was associated with positive patient-reported outcomes. Insulin human inhalation powder is an effective and generally well-tolerated agent for the prandial treatment of hyperglycaemia in T1DM and T2DM patients and may provide a solution to insulin initiation barriers such as injection phobia, concerns of bodyweight gain and concerns of hypoglycaemia.

Impact of symptomatic upper respiratory tract infections on insulin absorption and action of Technosphere inhaled insulin

OBJECTIVE

Uncomplicated, acute upper respiratory tract infections (URTIs) occur in patients with diabetes at a similar frequency to the general population. This study (NCT00642681) investigated the effect of URTIs on the pharmacokinetic (PK) and pharmacodynamic (PD) properties of Technosphere inhaled insulin (TI) in patients with type 1 or type 2 diabetes.

RESEARCH DESIGN AND METHODS

This was a phase 2 study conducted in patients who developed a URTI while being treated with TI in a phase 3 study (N=20, mean age 50 years, 60% men). Patients underwent two 4-hour meal challenges, during which blood samples were drawn to measure serum fumaryl diketopiperazine (FDKP; the excipient representing an essential part of TI), serum insulin, serum C-peptide, and plasma glucose. The primary outcome was the ratio of serum FDKP area under the concentration-time curve from 0 to 240 min (AUC0-240 min) during URTI and after clinical resolution of URTI symptoms (≥15 to ≤45 days).

RESULTS

No significant differences in PK parameters were seen during URTI versus post-URTI for FDKP. The ratio of serum FDKP AUC0-240 min during URTI and post-URTI was 1.1 (SD 0.6), p=0.4462. Plasma glucose concentrations during each 4-hour meal challenge were similar, showing small non-significant differences. No adverse events, including hypoglycemia, occurred during meal challenge visits.

CONCLUSIONS

Development of an active, symptomatic URTI during treatment with TI had no significant impact on the PK/PD properties of TI, suggesting that no adjustment in prandial insulin dosing is needed. However, if patients are unable to conduct proper inhalation, they should administer their prandial insulin subcutaneously.

TRIAL REGISTRATION NUMBER

NCT00642681; Results.

Technosphere insulin: inhaled prandial insulin

INTRODUCTION

Insulin therapy is a mainstay for treatment of diabetes mellitus; however, many barriers to insulin exist. Insulin human inhalation powder (technosphere insulin) is a new FDA-approved alternative to subcutaneous bolus insulin.

AREAS COVERED

This is an overview of technosphere insulin (TI). Pharmacokinetics, clinical efficacy, safety and tolerability are discussed.

EXPERT OPINION

TI is more quickly absorbed than subcutaneous insulin therapies and has a shorter duration of action. It appears to be noninferior compared with subcutaneous insulin regimens, and is associated with less hypoglycemia. Thus, it may serve as an alternative insulin agent in patients reluctant to administer multiple subcutaneous injections of insulin daily or in patients who experience late postprandial hypoglycemia with subcutaneous insulin. Cough is the most common side effect, but tends to be mild and transient. A small decrease in the forced expiratory volume has been demonstrated, but does not appear to progress and is reversible. Patients should have periodic pulmonary function tests. TI is contraindicated in patients with chronic lung disease. The long-term risk of lung cancer is being monitored but at this point does not appear to be higher than the expected incidence of lung cancer in this population.

Controlled release of biologics for the treatment of type 2 diabetes

Type 2 diabetes is a rapidly growing disease that poses a significant burden to the United States healthcare system. Despite the many available treatments for the disease, close to half of diagnosed type 2 diabetes cases are not properly managed, largely due to inadequate patient adherence to prescribed treatment regimens. Methods for improving delivery - and thereby easing administration - of type 2 drugs have the potential to greatly improve patient health. This review focuses on two peptide drugs - insulin and glucagon-like peptide 1 (GLP-1) - for treatment of type 2 diabetes. Peptide drugs offer the benefits of high potency and specificity but pose a significant delivery challenge due to their inherent instability and short half-life. The development of insulin and GLP-1 analogs highlights the broad spectrum of drug delivery strategies that have been used to solve these problems. Numerous structural modifications and formulations have been introduced to optimize absorption, residence time, stability, route of delivery and frequency of administration. Continual improvements in delivery methods for insulin and GLP-1 receptor agonists are paving the way towards better patient compliance and improved disease management, and thereby enhanced patient quality of life.

Efficacy, safety, and patient acceptability of Technosphere inhaled insulin for people with diabetes: a systematic review and meta-analysis

BACKGROUND

Technosphere inhaled insulin is a non-invasive alternative to subcutaneous injectable insulin for adults with type 1 or 2 diabetes. In this systematic review and meta-analysis of randomised controlled trials, we aimed to establish the efficacy, safety, and patient acceptability of Technosphere inhaled insulin in patients with diabetes.

METHODS

We searched MEDLINE, the Cochrane Central Register of Controlled Clinical Trials, ClinicalTrials.gov, and relevant US regulatory documents for reports of randomised trials published in English up to May 30, 2015, that compared mealtime Technosphere inhaled insulin with placebo, subcutaneous insulin, or oral antidiabetic drugs in people with type 1 or type 2 diabetes. Two reviewers independently extracted data for outcomes of interest and risk of bias. Endpoints included changes in HbA1c concentration and bodyweight, and safety outcomes, including severe hypoglycaemia and pulmonary toxicity. When three or more studies provided relevant data, we did a meta-analysis for the outcome using a profile-likelihood random-effects model.

FINDINGS

13 trials met the inclusion criteria for qualitative systematic review; 12 met the inclusion criteria for quantitative meta-analysis (n=5273; age range 18-80). HbA1c decrease from baseline was greater with subcutaneous insulin than with Technosphere inhaled insulin (net difference 0·16%, 95% CI 0·06-0·25; eight trials). However, inhaled insulin was associated with less weight gain (net difference -1·1 kg, -2·1 to -1·6; three trials) and a smaller risk of severe hypoglycaemia (odds ratio 0·61, 95% CI 0·35-0·92; five trials). Incidence of mild transient cough was increased in people allocated to inhaled insulin (odds ratio 7·82, 6·14-10·15; seven trials) compared with those allocated to active comparator groups, as was the decrease in forced expiratory volume in 1 s (net difference -0·038 L, -0·049 to -0·026; five trials). Quality of life and overall patient satisfaction did not differ significantly between inhaled insulin groups and active comparator groups (no numerical estimate).

INTERPRETATION

Glycaemic efficacy of Technosphere inhaled insulin is lower than that of subcutaneous insulin, but inhaled insulin has a lower risk of severe hypoglycaemia and weight gain. Long-term outcomes and safety with Technosphere insulin should be further investigated. Until further data for safety become available, Technosphere inhaled insulin should be reserved for healthy adults with diabetes who do not have pulmonary disease and who would otherwise delay initiating or intensifying insulin therapy because they are unwilling or unable to use injectable insulin.

FUNDING

None.

Clinical results of an automated artificial pancreas using technosphere inhaled insulin to mimic first-phase insulin secretion

OBJECTIVE

The purpose of this study was to investigate whether or not adding a fixed preprandial dose of inhaled insulin to a fully automated closed loop artificial pancreas would improve the postprandial glucose control without adding an increased risk of hypoglycemia.

RESEARCH DESIGN AND METHODS

Nine subjects with T1DM were recruited for the study. The patients were on closed-loop control for 24 hours starting around 4:30 pm. Mixed meals (~50 g CHO) were given at 6:30 pm and 7:00 am the following day. For the treatment group each meal was preceded by the inhalation of one 10 U dose of Technosphere Insulin (TI). Subcutaneous insulin delivery was controlled by a zone model predictive control algorithm (zone-MPC). At 11:00 am, the patient exercised for 30 ± 5 minutes at 50% of predicted heart rate reserve.

RESULTS

The use of TI resulted in increasing the median percentage time in range (70-180 mg/dl, BG) during the 5-hour postprandial period by 21.6% (81.6% and 60% in the with/without TI cases, respectively, P = .06) and reducing the median postprandial glucose peak by 33 mg/dl (172 mg/dl and 205 mg/dl in the with and without TI cases, respectively, P = .004). The median percentage time in range 80-140 mg/dl during the entire study period was 67.5% as compared to percentage time in range without the use of TI of 55.2% (P = .03).

CONCLUSIONS

Adding preprandial TI (See video supplement) to an automated closed-loop AP system resulted in superior postprandial control as demonstrated by lower postprandial glucose exposure without addition hypoglycemia.

Pharmacologic Treatment of Type 2 Diabetes

Objective: To review the oral and injectable pharmacologic treatment options for type 2 diabetes. Data Sources: A literature search was conducted using PubMed electronic database for studies published in English between 1993 and September 2014. Search terms included diabetes mellitus, type 2 diabetes, and the individual name for each antidiabetic medication reviewed. In addition, manual searches were performed for cross-references from publications. Package inserts, United States Food and Drug Administration (FDA) Web site, Institute for Safe Medication Practices Web site, American Diabetes Association Web site and scientific session poster presentations, and individual drug company Web pages were also reviewed. Study Selection and Data Extraction: This review focused on information elucidated over the past 10 years to assist prescribers in choosing optimal therapy based on individual patient characteristics. Studies leading to the approval of or raising safety concerns for the antidiabetic medications reviewed in this article were included. Data Synthesis: In the past 10 years, there have been 4 novel oral antidiabetic medication classes and 10 new injectable agents and insulin products approved by the FDA for the treatment of type 2 diabetes as well as new information regarding the safety and use of several older antidiabetic medication classes. The distinctions were reviewed for each individual agent, and a comparison was completed if there was more than one agent in a particular therapeutic class. Using current information available, select investigational agents in phase III trials or with a pending new drug application were highlighted. Conclusion: There are now 9 distinct oral pharmacologic classes and a variety of insulin and noninsulin injectable medications available for the treatment of type 2 diabetes. Metformin remains the first-line treatment option for most patients. When considering options for alternative or additional treatment, prescribers must weigh the benefits and risks using individual patient characteristics.

Technosphere insulin (Afrezza): a new, inhaled prandial insulin

OBJECTIVE

To review the pharmacology, pharmacokinetics, safety, and efficacy of Technosphere insulin (TI), a new inhaled insulin product.

DATA SOURCES

Searches were conducted in PubMed/MEDLINE, Scientific Citation Index, and abstracts from both the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD) meetings from 2005 to August 2014, utilizing the search terms Afrezza, Technosphere, Afresa, and inhaled insulin. References were reviewed to identify additional sources.

STUDY SELECTION AND DATA EXTRACTION

Studies with adequate sample sizes, evaluating clinically relevant end points were included.

DATA SYNTHESIS

TI is approved by the Food and Drug Administration as a bolus insulin to treat patients with type 1 and type 2 diabetes. Its glucose-lowering properties are less than that of rapid-acting insulins, but it does demonstrate less hypoglycemia. TI's kinetics make it the fastest absorbed of any insulin available, although its overall onset of action appears similar to insulin lispro. It represents an alternative to bolus injections but would likely be used concomitantly with injected basal insulin. Major adverse effects are respiratory in nature, with cough being the most prominent. There is a small decrease in the forced expiratory volume in 1 s (FEV1) with TI; this appears to be consistent, nonprogressive, and reversible. Patients using TI must receive pulmonary function tests periodically throughout therapy. TI is contraindicated in patients with chronic lung disease and should be used with caution in patients who smoke.

CONCLUSION

TI is a novel inhaled insulin that provides prandial coverage to patients with diabetes, representing an alternative to bolus insulin injections.

New developments in insulin therapy for type 2 diabetes

Insulin has classically been considered a treatment of last resort for individuals with type 2 diabetes, delayed until all other efforts by the patient and healthcare provider have failed. Recent treatment guidelines recommend the use of insulin, in particular basal insulin, as part of a treatment regimen earlier in the disease process. Many patients are reticent about initiating insulin, so therapies that allow insulin treatment to be more tailored to individual needs are likely to result in greater acceptance and patient adherence with therapy. To meet this need, a range of insulin products are in development that aim to increase absorption rate or prolong the duration of action, reduce peak variability and weight gain associated with insulin treatment, and offer alternative delivery methods. This review describes insulin products in clinical development, new combination therapies, and new devices for insulin delivery.

Inhaled insulin: a breath of fresh air? A review of inhaled insulin

PURPOSE

Despite many advances in diabetes care over the last century, some elements of insulin therapy remain inadequate for optimal care of the patient with diabetes. There is a need for improved pharmacokinetics and pharmacodynamics of rapid-acting insulin analogues to mimic physiologic insulin secretion. In addition, a major barrier to successful insulin therapy has been patient resistance. Alternative routes of insulin administration, including inhaled insulin, have been under investigation for several years. This review discusses the rationale for pulmonary delivery of insulin, compares previous inhaled insulin products, reviews the literature on the safety and efficacy of a current inhaled insulin formulation under investigation, and compares this product with other prandial insulin products.

METHODS

English-language studies and reviews of inhaled insulin were searched in MEDLINE, the ClinicalTrials.gov registry (through May 2014), and the US Food and Drug Administration Website.

FINDINGS

Inhaled insulin has several favorable characteristics due to pulmonary anatomy/physiology and the lack of injections. Pharmacokinetic and pharmacodynamic studies have shown a time-action profile suitable for prandial insulin use. Inhaled insulin seems to be safe and effective compared with other prandial insulin products and may be preferable to subcutaneous rapid-acting insulin analogues in terms of time-action profiles and rates of hypoglycemia. Small decreases in forced expiratory volume in 1 second (FEV1) have been shown with inhaled insulin, although this finding is not progressive over time and reverses with cessation of the medication.

IMPLICATIONS

Although several inhaled insulin products have been under investigation, only one (Exubera(®) [Nektar Therapeutics, San Carlos, California/Pfizer Inc, New York, New York]) was approved by the US Food and Drug Administration, and it was pulled from the market after only a short period of time. Technosphere(®) insulin (MannKind Corporation, Valencia, California) is currently the only inhaled insulin that remains under investigation. A review of the past and present literature on inhaled insulin is pertinent in understanding the current status of inhaled insulin and its risks and benefits. The current literature suggests that inhaled insulin could be a valuable option for prandial insulin administration, with a favorable risk to benefit ratio in some patients.

Systemic delivery of biotherapeutics through the lung: opportunities and challenges for improved lung absorption

The development of Exubera(®) (inhaled insulin) has paved the way for consideration of future inhaled biotherapeutic products for systemic delivery. This route of drug delivery favors highly potent small peptides without self-association and large proteins resistant to enzymatic degradation for high bioavailability, while likely resulting in transient therapeutic effects. Improved therapeutic benefits with a needle-free delivery, such as inhaled insulin, are also rational pursuits. Molecules and their formulations must be carefully chosen and designed to optimize the rates of lung absorption and nonabsorptive loss. Novel molecular or formulation approaches, for example, Technosphere(®), Fc-/scFv-fusion protein, PEGylation, polymeric or lipid-based micro/nanoparticles and liposomes, offer opportunities to improve lung absorption and therapeutic duration of some biotherapeutics. Critical assessments are now essential as to their therapeutic benefits, safety, patient acceptance and market competition, as carried out for Exubera.

New and Future Medications for the Treatment of Type 2 Diabetes Mellitus

With almost 30 million individuals predicted to be diagnosed by the year 2025, type 2 diabetes mellitus (T2DM) has become one of the most prevalent diseases in the United States. Because of the progressive dysfunction of the pancreatic β-cells and increasing insulin resistance over time, the need for treatments with different mechanisms or addition of medications to a regimen is becoming commonplace. Because of this, developing new medications to treat T2DM has been the focus of a lot of recent research and drug development. Molecular substrates such as glucagon-like peptide-1 (GLP-1), dipeptidyl peptidase-4 (DPP-4), and the sodium glucose transporter-2 (SGLT2) have all become new therapeutic targets. GLP-1 agonists and DPP-4 inhibitors are 2 of the newest classes of Food and Drug Administration–approved medications for diabetes. By increasing GLP-1 to supraphysiologic levels (GLP-1 agonists) and delaying endogenous GLP-1 degradation (DPP-4 inhibitors), these drugs increase insulin secretion and decrease glucagon production. SGLT2 inhibitors, the newest antihyperglycemic class, promote glycosuria by inhibiting sodium and glucose reabsorption in the proximal tubule of the renal nephron. Other novel agents for the treatment of diabetes include the use of the dopamine agonist bromocriptine, the cholesterol medication colesevelam, and a new form of inhaled insulin.

In silico evaluation of an artificial pancreas combining exogenous ultrafast-acting technosphere insulin with zone model predictive control

BACKGROUND

Because of the slow pharmacokinetics of subcutaneous (SC) insulin, avoiding postprandial hyperglycemia has been a major challenge for an artificial pancreas (AP) using SC insulin without a meal announcement.

METHODS

A semiautomated AP with Technosphere® Insulin (TI; MannKind Corporation, Valencia, CA) was designed to combine pulmonary and SC insulin. Manual inhalation of 10 U ultrafast-absorbing TI at mealtime delivers the first, or cephalic, phase of insulin, and an SC insulin pump controlled by zone model predictive controller delivers second-phase and basal insulin. This AP design was evaluated on 100 in silico subjects from the University of Virginia/Padova metabolic simulator using a protocol of two 50 g carbohydrate (CHO) meals and two 15 g CHO snacks.

RESULTS

Simulation analysis shows that the semiautomated AP with TI provides 32% and 16% more time in the controller target zone (80-140 mg/dl) during the 4 h postprandial period, with 39 and 20 mg/dl lower postprandial blood glucose peak on average than the pure feedback AP and the AP with manual feed-forward SC bolus, respectively. No severe hypoglycemia (<50 mg/dl) was observed in any cases.

CONCLUSIONS

The semiautomated AP with TI provides maximum time in the clinically accepted region when compared with pure feedback AP and AP with manual feed-forward SC bolus. Furthermore, the semiautomated AP with TI provides a flexible operation (optional TI inhalation) with minimal user interaction, where the controller design can be tailored to specific user needs and abilities to interact with the device.

Technosphere insulin effectively controls postprandial glycemia in patients with type 2 diabetes mellitus

BACKGROUND

This pilot trial was designed to determine if an optimal dose of Technosphere(®) insulin (TI) inhalation powder (MannKind Corp., Valencia, CA) could be used regardless of variation in meal carbohydrate (CHO) content.

SUBJECTS AND METHODS

In total, eight subjects (seven men, one woman) with type 2 diabetes were enrolled. Subjects underwent dose optimization meal challenge (MC) visits (100% CHO) and MCs with varied CHO meal contents (50%, 200%, and 0% calculated CHOs). Primary end point was change in postprandial glucose (PPG) excursions. Baseline demographics were 60±7 years of age, diabetes duration of 12.3±4.27 years, hemoglobin A1c (A1C) of 7.82±1.04%, and body mass index of 31.3±5.48 kg/m(2).

RESULTS

Maximum mean PPG excursions for the nominal 100% CHO meals were -13±15 mg/dL for breakfast (B) and -14±15 mg/dL for lunch (L), similar to those after 50% CHO meals (B, -17±16 mg/dL; L, +14±10 mg/dL). The largest excursions occurred during 200% CHO meals and remained below American Diabetes Association targets (B, +19±16 mg/dL; L, +32±29 mg/dL). During 15 of the MCs, subjects took their usual TI dose and then had no meal (0% CHO). For the 0% CHO MCs, the largest mean PPG excursion were -33±9 mg/dL at 60 min (B) and -31±10 mg/dL at 60 and 90 min (L). Mean A1C dropped from 7.82±1.04% at the Week 1 visit to 6.18±0.46% (P=0.00091) at the Week 19 visit.

CONCLUSIONS

Results in eight patients suggest that once an optimal dose of TI is determined, type 2 diabetes patients can ingest meals with a wide range of CHO content or even skip meals without severe hypoglycemia. During this pilot study TI therapy improved A1C by -1.63% (P=0.00091) during 19 weeks of treatment.

Novel non-invasive methods of insulin delivery

INTRODUCTION

Insulin has usually been administered subcutaneously in the treatment of diabetes mellitus. Alternative delivery routes of insulin are expected to overcome some limitations, mainly concerned with the possibility of hypoglycemia episodes, weight gain and inadequate post-meal glucose control, in order to lead a better patient compliance.

AREAS COVERED

This review article covers all the most relevant non-invasive insulin delivery methods under development, respective technology and clinical data available according to their status of development. Special focus is given to the systems with late clinical trial evidences, their achievements and pitfalls. Pulmonary and oral appear to be the most advantageous routes, with regard to the long list of potentially marketed products.

EXPERT OPINION

Alternative insulin delivery to the subcutaneous administration is more and more close to the success, being fundamental that any optimized technology could overcome the overall low mucosal bioavailability of insulin, mostly due to its early degradation before absorption, inactivation and digestion by proteolytic enzymes and poor permeability across mucosal epithelium because of its high molecular weight and lack of lipophilicity.

The pharmacokinetics and pharmacodynamics of rapid-acting insulin analogues and their clinical consequences

Postprandial glucose excursions can inhibit achievement of good glycaemic control, and possibly have a specific effect on the risk of vascular comorbidities. Rapid-acting analogues control these excursions better than human insulin because their pharmacokinetic/pharmacodynamic (PK/PD) profile is closer to that of meal-time endogenous insulin secretion. Review of the findings of PK/PD studies and clinical trials suggests that the three marketed rapid-acting analogues--insulin lispro, insulin aspart and insulin glulisine--are equally efficacious and safe. In comparison with human insulin when using the same basal insulin, they provide comparable glycaemic control with a reduced risk of hypoglycaemia, although the combination of rapid-acting and basal analogues reduces glycated haemoglobin (HbA(1c)) more than human meal-time insulin combined with neutral protamine Hagedorn (NPH) insulin. Some studies have suggested that insulin glulisine has a slightly faster onset of action compared with insulin lispro or insulin aspart, but this has not been translated into demonstrable clinical benefit. Treatment satisfaction in patients with diabetes has been higher when therapy with a rapid-acting analogue is used instead of human insulin, perhaps due to differences in advised timing of injection. The largest benefits in efficacy, hypoglycaemia incidence, treatment satisfaction and quality of life have occurred when patients receive an all-analogue meal-time plus basal regimen as compared with an all-human insulin regimen. No new safety issues have been identified with the marketed rapid-acting analogues, and their insulin-like growth factor 1 receptor affinity and mitogenic activity are comparable to human insulin.

Pharmacokinetics and postprandial glycemic excursions following insulin lispro delivered by intradermal microneedle or subcutaneous infusion

BACKGROUND

Intradermal (ID) delivery has been shown to accelerate insulin pharmacokinetics (PK). We compared the PK and pharmacodynamic (PD) effects of insulin lispro administered before two daily standardized solid mixed meals (breakfast and lunch), using microneedle-based ID or traditional subcutaneous (SC) delivery.

METHOD

The study included 22 subjects with type 1 diabetes in an eight-arm full crossover block design. One arm established each subject's optimal meal dose. In six additional arms, the optimal, higher, and lower doses (+30%, -30%) were each given ID and SC delivery, in random order. The final arm assessed earlier timing for the ID optimal dose (-12 versus -2 min). The PK/PD data were collected for 6 h following meals. Intravenous basal regular insulin was given throughout, and premeal blood glucose (BG) adjusted to 115 mg/dl.

RESULTS

The primary end point, postprandial time in range (70-180 mg/dl), showed no route-based differences with a high level of overall BG control for both SC and ID delivery. Secondary insulin PK end points showed more rapid ID availability versus SC across doses and meals (∆Tmax -16 min, ∆T50rising -7 min, ∆T50falling -30 min, all p < .05). Both intrasubject and intersubject variability for ID Tmax were significantly lower. Intradermal delivery showed modest, statistically significant secondary PD differences across doses and meals, generally within 90-120 min postprandially (∆12 mg/dl BG at 90 min, ∆7 mg/dl BGmax, ∆7 mg/dl mean BG 0-2 h, all p < .05).

CONCLUSIONS

This study indicates that ID insulin delivery is superior to SC delivery in speed of systemic availability and PK consistency and may improve postprandial glucose control.

Coverage of prandial insulin requirements by means of an ultra-rapid-acting inhaled insulin

Barriers to the use of prandial insulin regimens include inadequate synchronization of insulin action to postprandial plasma glucose excursions as well as a significant risk of hypoglycemia and weight gain. Technosphere® insulin (TI) is an inhaled ultra-rapid-acting human insulin that is quickly absorbed in the alveoli. With a time to maximum plasma drug concentration of approximately 14 min and a time to maximum effect of 35 to 40 min, TI more closely matches the postprandial insulin concentrations seen in nondiabetic individuals. Studies have shown that long-term administration of prandial TI in combination with long-acting basal insulin results in reductions in hemoglobin A1c comparable to conventional subcutaneously injected prandial insulins but with improved control of early postprandial BG. Furthermore, TI has been associated with less weight gain and a lower incidence of hypoglycemia, which may enhance patient satisfaction and acceptability of insulin therapy. This review discusses the clinical properties of TI and proposes strategies for optimal use.

Ultrafast-acting insulins: state of the art

Optimal coverage of prandial insulin requirements remains an elusive goal. The invention of rapid-acting insulin analogs (RAIAs) was a big step forward in reducing postprandial glycemic excursions in patients with diabetes in comparison with using regular human insulin; however, even with these, the physiological situation cannot be adequately mimicked. Developing ultrafast-acting insulins (UFIs)-showing an even more rapid onset of action and a shorter duration of action after subcutaneous (SC) administration-is another step forward in achieving this goal. The need for UFIs has been gradually recognized over the years, and subsequently, a number of different approaches to cover this need are in clinical development. A rapid increase in circulating insulin levels can be achieved by different measures: modification of the primary structure of insulin molecule (as we know from RAIAs), addition of excipients that enhance the appearance in the monomeric state post-injection, or addition of enzymes that enable more free spreading of the insulin molecules in the SC tissue. Other measures to increase the insulin absorption rate increase the local blood flow nearby the insulin depot in the SC tissue, injecting the insulin intradermally or applying via another route, e.g., the lung. The development of these approaches is in different stages, from quite early stages to nearing market authorization. In time, daily practice will show if the introduction of UFIs will fulfill their clinical promise. In this review, the basic idea for UFIs will be presented and the different approaches will be briefly characterized.

Special considerations with insulin therapy in older adults with diabetes mellitus

Aging is associated with alterations in insulin secretion and action. However, aging per se does not alter the pharmacokinetics of commercially available insulin and its analogues. Insulin therapy in older adults is complicated by psychosocial and physiological changes of aging. Several new insulin and insulin analogue preparations are now available for clinical use. Used as prandial (e.g. insulin lispro, insulin aspart or insulin glulisine) and basal insulin (e.g. insulin glargine, insulin detemir), these analogues simulate physiological insulin profiles more closely than the older conventional insulins. The availability of multiple insulin products provides new opportunities to achieve control of diabetes mellitus. The choice of initial insulin therapy can be made based on blood glucose profiles. Overall, these profiles can be divided into three general patterns that include: (i) round-the-clock hyperglycaemia; (ii) fasting hyperglycaemia with daytime euglycaemia; and (iii) daytime hyperglycaemia with normal fasting blood glucose levels. The prescription of insulin is a dynamic process, and the insulin regimen should be adjusted based on individual response. The goal of diabetes care in older adults is to enhance quality of life without subjecting individuals to complicated treatment regimens that may interfere with their independence in carrying out daily activities.

Clinical hurdles and possible solutions in the implementation of closed-loop control in type 1 diabetes mellitus

From an engineering perspective, controlling blood glucose appears to be a fairly straightforward single input (glucose), single output (insulin) control problem. Unfortunately, mimicking Mother Nature turns out to be a complex endeavor. The primary hurdle in developing a useful, safe closed-loop control algorithm for an artificial pancreas is the time delays associated with current continuous glucose monitors and subcutaneously delivered insulins. This article will provide a brief history of the artificial pancreas, outline the main clinical hurdles restricting its current implementation, and list possible solutions for success.

Insulin lung deposition and clearance following Technosphere® insulin inhalation powder administration

PURPOSE

To determine distribution and deposition of Technosphere® Insulin (TI) inhalation powder and the rate of clearance of fumaryl diketopiperazine (FDKP; major component of Technosphere particles) and insulin from the lungs.

METHODS

Deposition and distribution of (99m)pertechnetate adsorbed onto TI immediately after administration using the MedTone® inhaler was quantified by gamma-scintigraphy. Clearance from the lungs was studied in a second experiment by serial bronchoalveolar lavage (BAL) after administration of TI inhalation powder and assay of the recovered fluid for FDKP and insulin.

RESULTS

Following inhalation, ~60% of radioactivity (adsorbed on TI) emitted from the inhaler was delivered to the lungs; the remainder of the emitted dose was swallowed. Clearance from the lung epithelial lining fluid (ELF) of FDKP and insulin have a half-life of ~1 hour.

CONCLUSION

TI inhalation powder administered via the MedTone inhaler was uniformly distributed throughout the lungs; ~40% of the initial cartridge load reached the lungs. Insulin and FDKP are quickly cleared from the lungs, mainly by absorption into the systemic circulation. The terminal clearance half-life from the lung ELF, estimated from sequential BAL fluid measurements for both components, was ~1 hour. Since there is an overnight washout period, the potential for accumulation on chronic administration is minimal.

A new C-Peptide correction model used to assess bioavailability of regular human insulin

The clinical assessment of new formulations of human insulin is problematic due to the inability to distinguish between endogenous insulin and exogenously administered insulin. The usual methods to surmount the problem of distinguishing between endogenous and exogenous human insulin include evaluation in subjects with no or little endogenous insulin, hyper-insulinemic clamp studies or the administration of somatostatin to suppress endogenous insulin secretion. All of these methods have significant drawbacks. This paper describes a method for C-Peptide correction based upon a mixed effects linear regression of multiple time point sampling of C-Peptide and insulin. This model was able to describe each individual's insulin to C-Peptide relationship using the data from four different phase I clinical trials involving both subjects with and without type 2 diabetes in which insulin and C-Peptide were measured. These studies used hyper-insulinemic euglycemic clamps or meal challenges and subjects received insulin or Glucagon-like peptide 1 (GLP-1). It was possible to determine the exogenously administered insulin concentration from the measured total insulin concentration. A simple statistical technique can be used to determine each individual's insulin to C-Peptide relationship to estimate exogenous and endogenous insulin following the administration of regular human insulin. This technique will simplify the assessment of new formulations of human insulin.

Pharmacokinetic characterization of the novel pulmonary delivery excipient fumaryl diketopiperazine

BACKGROUND

Technosphere® [Bis-3,6(4-fumarylaminobutyl)-2,5-diketopiperazine (FDKP)] microparticles, the integral component of the Technosphere inhalation system, deliver drugs to the deep lung and have been used to administer insulin and glucagon-like peptide-1 via inhalation in clinical studies. Three studies were conducted to characterize FDKP pharmacokinetics, including assessments in subjects with diabetic nephropathy (DNP), in subjects with chronic liver disease (CLD), and in healthy subjects.

METHODS

An open-label, nonrandomized, two-period, fixed-sequence crossover absorption, distribution, metabolism, and excretion (ADME) study was conducted in six healthy nonsmoking men who received single intravenous and oral doses of [(14)C]FDKP solution, with serial sampling of blood, urine, feces, and expired air. Additionally, two single-dose, open-label, parallel-design studies with 20 mg of inhaled FDKP were conducted in (1) 12 diabetic subjects with normal renal function and 24 DNP subjects and (2) 12 healthy subjects and 21 CLD subjects.

RESULTS

In the ADME study, >95% of the intravenous dose and <3% of the oral dose were recovered in urine, with no evidence of metabolism. No significant pharmacokinetic differences were observed between healthy subjects and CLD subjects [geometric mean (% coefficient of variation) area under the curve from time 0 to 480 minutes (AUC(0-480)): 26,710 (34.8) and 31,477 (28.8) ng/ml·min, respectively]. Maximum observed drug concentration (C(max)) and AUC(0-480) were higher in DNP subjects than in subjects with normal renal function [C(max): 159.9 (59.4) ng/ml versus 147.0 (44.3) ng/ml; AUC(0-480): 36,869 (47.2) ng/ml·min versus 30,474 (31.8) ng/ml·min]. None of the differences observed were considered clinically significant.

CONCLUSIONS

Fumaryl diketopiperazine is predominantly cleared unchanged by the kidney with essentially no oral bioavailability. Technosphere is a safe delivery vehicle for medications administered via inhalation.

A Review of Inhaled Technosphere Insulin

Objective:

To review the pharmacology, pharmacokinetics, efficacy, safety, and clinical use of Technosphere insulin.

Data Sources:

A MEDLINE search (1966–March 2010) was conducted for English-language articles using the terms AFREZZA, AFRESA, Technosphere insulin, pulmonary insulin, and inhaled insulin. Abstracts from the American Diabetes Association and European Association for the Study of Diabetes annual meetings, presented in 2004, 2005, 2006, 2007, 2008, and 2009 were also searched for relevant data.

Study Selection and Data Extraction:

English-language articles pertinent to the pharmacology, pharmacokinetics, efficacy, and safety of Technosphere insulin were reviewed.

Data Synthesis:

Technosphere insulin is an inhaled insulin product with a pharmacokinetic profile suitable to meet prandial insulin needs in patients with diabetes. Technosphere insulin has demonstrated efficacy in terms of postprandial and overall glycemic control, with efficacy and safety outcomes maintained for up to 4 years in one study. The overall tolerability profile for Technosphere insulin in clinical trials published to date has demonstrated a relatively low risk of hypoglycemia and weight gain when compared with subcutaneous mealtime insulins. Clinical trials to date have demonstrated safety in terms of pulmonary function, and the absorption of Technosphere insulin is not significantly altered in patients with chronic obstructive pulmonary disease or in those who smoke.

Conclusions:

The Technosphere delivery system allows for the rapid absorption of Technosphere insulin via the lung, making this product a potential option for prandial insulin coverage in both type 1 and type 2 diabetes. The device to administer the insulin is well designed, small, and easy to use. Technosphere inhaled insulin may provide a useful treatment option for patients resistant to or fearful of initiating prandial insulin injections.

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.

Review of the mechanism of action and clinical efficacy of recombinant human hyaluronidase coadministration with current prandial insulin formulations

For patients with type 1 or type 2 diabetes, achieving good glycemic control is critical for successful treatment outcomes. As many patients remain unable to reach glycemic goals with currently available rapid-acting analog insulins, ultrafast insulin products are being developed that provide an even faster pharmacokinetic profile compared with current rapid prandial insulin products. The overall strategy of these ultrafast insulin products is to better mimic the normal physiologic response to insulin that occurs in healthy individuals to further improve glycemic control. Recombinant human hyaluronidase (rHuPH20) is a genetically engineered soluble hyaluronidase approved by the U.S. Food and Drug Administration as an adjuvant to increase the absorption and dispersion of other injected drugs; mammalian hyaluronidases as a class have over 6 decades of clinical use supporting the safety and/or efficacy of hyaluronidase coadministration. Clinical findings have demonstrated that coadministration of rHuPH20 with insulin or an insulin analog achieved faster systemic absorption, reduced inter- and intrapatient variability of insulin absorption, and achieved faster metabolic effects compared with injection of either insulin formulation alone. The magnitude of this acceleration is similar to the incrementally faster absorption of prandial insulin analogs as compared with regular insulin. In addition, coadministration of rHuPH20 with regular insulin or insulin analog also improved the achievement of prandial glycemic targets. Thus, rHuPH20 coadministration shows promise as a method of establishing a more rapid insulin profile to prandial insulin in patients with diabetes and has the potential to yield substantial improvements in postprandial glycemic excursion.