Novopen Echo® for the delivery of insulin: a comparison of usability, functionality and preference among pediatric subjects, their parents, and health care professionals

Development of an Insulin Pen is a Patient-Centric Multidisciplinary Undertaking: A Commentary

The goal of human-centered insulin pen design is to relieve the treatment burden of a chronic condition and help affected individuals to feel free of disease. The patient as well as their entire ecosystem should be considered. At Novo Nordisk A/S, we believe that embedding human-centered design at the heart of our development processes is best achieved with multidisciplinary experts in-house to work alongside product development teams and, importantly, the end user. Novo Nordisk introduced the first commercially available insulin pen in 1985 and has continued to develop reusable/durable and prefilled insulin pens to meet different patient needs, through to the latest NovoPen 6 and NovoPen Echo Plus with SMART technology. Human-centered design is essential for delivering meaningful and practical solutions for individuals with diabetes.

Digital Diabetes Management: A Literature Review of Smart Insulin Pens

Digital health management is increasingly pivotal in the care of patients with diabetes. The aim of this review was to evaluate the clinical benefits of using smart insulin pens with connectivity for diabetes management. The search was performed using PubMed and PubMed Central on May 15, 2019, to identify publications investigating the use of insulin pens. Studies evaluating insulin pens with connectivity via Bluetooth/Near Field Communication, with an associated electronic device enabling connectivity, or with a memory function were included in the review. Nine studies were identified in the search. Overall, these studies lacked data on smart insulin pens with a connectivity function, with eight of the available studies investigating only pens with a memory function. The studies focused primarily on assessing patient preference, usability, and technical accuracy. The number of studies assessing clinical outcomes was small (n = 3). However, the majority of studies (n = 8) reported that patients preferred smart insulin pens because they increased confidence with regard to diabetes self-management. These results suggest a lack of published data regarding smart insulin pens with connectivity for the management of diabetes. However, the available published data on usability and patient preference suggest that the use of smart insulin pens holds promise for improving and simplifying diabetes self-management.

The Review of Insulin Pens-Past, Present, and Look to the Future

Currently, there are about 150-200 million diabetic patients treated with insulin globally. The year 2021 is special because the 100th anniversary of the insulin discovery is being celebrated. It is a good occasion to sum up the insulin pen technology invention and improvement which are nowadays the leading mode of an insulin delivery. Even though so many years have passed, insulin is still administered subcutaneously, that is why devices to deliver it are of great importance. Insulin pens have evolved only through the last decades (the reusable, durable pens, and the disposable, prefilled pens) and modern smart insulin pens have been developed in the last few years, and both types of the devices compared to traditional syringes and vials are more convenient, discrete in use, have better dosing accuracy, and improve adherence. In this review, we will focus on the history of insulin pens and their improvement over the previous decades.

Evolution of Insulin Delivery Devices: From Syringes, Pens, and Pumps to DIY Artificial Pancreas

The year 2021 will mark 100 years since the discovery of insulin. Insulin, the first medication to be discovered for diabetes, is still the safest and most potent glucose-lowering therapy. The major challenge of insulin despite its efficacy has been the occurrence of hypoglycemia, which has resulted in sub-optimal dosages being prescribed in the vast majority of patients. Popular devices used for insulin administration are syringes, pens, and pumps. An artificial pancreas (AP) with a closed-loop delivery system with > 95% time in range is believed to soon become a reality. The development of closed-loop delivery systems has gained momentum with recent advances in continuous glucose monitoring (CGM) and computer algorithms. This review discusses the evolution of syringes, disposable, durable pens and connected pens, needles, tethered and patch insulin pumps, bionic pancreas, alternate controller-enabled infusion (ACE) pumps, and do-it-yourself artificial pancreas systems (DIY-APS).

Insulin-delivery methods for children and adolescents with type 1 diabetes

Efforts directed toward restoring normal metabolic levels by mimicking the physiological insulin secretion, thereby ensuring safety, efficacy, minimal invasiveness and conveniences, are of great significance in the management of type 1 diabetes among children and adolescents. Regardless of the various technologies being discovered in addressing invasiveness and enhancing medication adherence in the management of type 1 diabetes, yet limited success had been observed among children and adolescents. The multiple daily subcutaneous insulin injections route using vial and syringe, and occasionally insulin pens, remain the most predictable route for insulin administration among children and adolescents. However, this route has been associated with compromised patient compliance, fear of injections and unacceptability, resulting in poor glycemic control, which promote the demand for alternative routes of insulin administration. Alternative routes for delivering insulin are being investigated in children and adolescents with type 1 diabetes; these include the hybrid closed-loop 'artificial pancreas' system, oral, inhalation, intranasal routes, and others. This review article explores the current advances in insulin-delivery methods that address the needs of children and adolescents in the treatment of type 1 diabetes.

Dose Accuracy, Injection Force, and Usability Assessment of a New Half-Unit, Prefilled Insulin Pen

BACKGROUND

This study examines the utility of the first prefilled, rapid-acting insulin pen that can be dialed in half-unit increments. Dose accuracy and injection force were examined through a series of design-verification tests, and usability was established by human factors validation testing.

METHODS

Devices were tested for dose accuracy at 3 different doses and temperatures and under free fall, vibration, and cold storage conditioning. Injection force was measured at the maximum dose (30 units). Both experiments used the same semiautomated testing system. Usability was validated in a human factors simulated-use study that included 60 participants (patients with type 1 or type 2 diabetes [aged 10-79 years], adult caregivers, and health care providers).

RESULTS

The pen met the International Organization for Standardization (ISO) 11608-1:2014 requirements for dose accuracy at all settings and conditions tested. Furthermore, all individual results were within the ISO specification limits. Mean injection force across temperature settings ranged from 9.25 to 10.85 N at the highest dose. The usability validation study confirmed that use-related risks were reduced to the extent possible and that additional modifications were not likely to afford further reductions.

CONCLUSIONS

The results from these studies demonstrated accurate dosing over the dose range (0.5-30 units) at different temperatures and conditions with an injection force that should accommodate the intended users. Use safety and usability in patients with diabetes, caregivers, and health care professionals were validated. The added convenience of this new half-unit, prefilled pen may ease the burden of diabetes management for patients who require smaller incremental dosing.

Half-Unit Insulin Pens: Disease Management in Patients With Diabetes Who Are Sensitive to Insulin

BACKGROUND

Insulin pens represent a significant technological advancement in diabetes management. While the vast majority have been designed with 1U-dosing increments, improved accuracy and precision facilitated by half-unit increments may be particularly significant in specific patients who are sensitive to insulin. These include patients with low insulin requirements and in those requiring more precise dose adjustments, such as the pediatric patient population. This review summarized functional characteristics of insulin half-unit pens (HUPs) and their effect on user experience.

METHODS

The literature search was restricted to articles published in English between January 1, 2000, and January 1, 2015. A total of 17 publications met the set criteria and were included in the review.

RESULTS

Overall, studies outlined characteristics for 4 insulin HUPs. Based on their functionality, the pens were generally similar and all met the ISO 11608-1 criteria for accuracy. However, some had specific advantageous features in terms of size, weight, design, dialing torque, and injection force. Although limited, the currently available user preference studies in children and adolescents with diabetes and their carers suggest that the selection of an HUP is likely to be influenced by a combination of factors such as these, in addition to the prescribed insulin and dosing regimen.

CONCLUSIONS

Insulin HUPs are likely to be a key diabetes management tool for patients who are sensitive to insulin; specific pen features may further advance diabetes management in these populations.

A Systematic Review of Patients' Perspectives on the Subcutaneous Route of Medication Administration

BACKGROUND

Subcutaneous injections allow for self-administration, but consideration of patients' perspectives on treatment choice is important to ensure adherence. Previous systematic reviews have been limited in their scope for assessing preferences in relation to other routes of administration.

OBJECTIVE

Our objective was to examine patients' perspectives on subcutaneously administered self-injectable medications when compared with other routes or methods of administration for the same medicines.

METHODS

Nine electronic databases were searched for publications since 2000 using terms pertaining to methods of administration, choice behavior, and adverse effects. Eligibility for inclusion was determined through reference to specific criteria by two independent reviewers. Results were described narratively.

RESULTS

Of the 1726 papers screened, 85 met the inclusion criteria. Studies were focused mainly on methods of insulin administration for diabetes but also included treatments for pediatric growth disorders, multiple sclerosis, HIV, and migraine. Pen devices and autoinjectors were favored over administration with needle and syringe, particularly with respect to ergonomics, convenience, and portability. Inhalation appeared to be more acceptable than subcutaneous injection (in the case of insulin), but how subcutaneous infusion, intramuscular injection, and needle-free injection devices compare with subcutaneous injections in terms of patient preference is less certain.

CONCLUSIONS

The review identified a number of studies showing the importance of the methods and routes of drug delivery on patient choice. However, studies were prone to bias, and further robust evidence based on methodologically sound approaches is required to demonstrate how patient choice might translate to improved adherence.

NovoPen Echo(®) insulin delivery device

The introduction of insulin pen devices has provided easier, well-tolerated, and more convenient treatment regimens for patients with diabetes mellitus. When compared with vial and syringe regimens, insulin pens offer a greater clinical efficacy, improved quality of life, and increased dosing accuracy, particularly at low doses. The portable and discreet nature of pen devices reduces the burden on the patient, facilitates adherence, and subsequently contributes to the improvement in glycemic control. NovoPen Echo^® is one of the latest members of the NovoPen^® family that has been specifically designed for the pediatric population and is the first to combine half-unit increment (=0.5 U of insulin) dosing with a simple memory function. The half-unit increment dosing amendments and accurate injection of 0.5 U of insulin are particularly beneficial for children (and insulin-sensitive adults/elders), who often require small insulin doses. The memory function can be used to record the time and amount of the last dose, reducing the fear of double dosing or missing a dose. The memory function also provides parents with extra confidence and security that their child is taking insulin at the correct doses and times. NovoPen Echo is a lightweight, durable insulin delivery pen; it is available in two different colors, which may help to distinguish between different types of insulin, providing more confidence for both users and caregivers. Studies have demonstrated a high level of patient satisfaction, with 80% of users preferring NovoPen Echo to other pediatric insulin pens.

Decision coaching using the Ottawa family decision guide with parents and their children: a field testing study

BACKGROUND

Although children can benefit from being included in health decisions, little is known about effective interventions to support their involvement. The objective of this study was to evaluate the feasibility and acceptability of decision coaching guided by the Ottawa Family Decision Guide with children and parents considering insulin delivery options for type 1 diabetes (insulin pump, multiple daily injections, or standard insulin injections).

METHODS

Pre-/post-test field testing design. Eligible participants were children (≤18 years) with type 1 diabetes and their parents attending an ambulatory diabetes clinic in a tertiary children's hospital. Parent-child dyads received decision coaching using the Ottawa Family Decision Guide that was pre-populated with evidence on insulin delivery options, benefits, and harms. Primary outcomes were feasibility of recruitment and data collection, and parent and child acceptability of the intervention.

RESULTS

Of 16 families invited to participate, 12 agreed and 7 attended the decision coaching session. For the five missed families, two families were unable to attend the session or the decision coach was not available (N=3). Baseline and immediately post-coaching questionnaires were all completed and follow-up questionnaires two weeks post-coaching were missing from one parent-child dyad. Missing questionnaire items were 5 of 340 items for children (1.5%) and 1 of 429 for parents (0.2%). Decision coaching was rated as acceptable with higher scores from parents and their children who were in earlier stages of decision making.

CONCLUSION

Decision coaching with children and their parents considering insulin options was feasible implement and evaluate in our diabetes clinic and was acceptable to participants. Recruitment was difficult due to scheduling restrictions related to the timing of the study. Coaching should target participants earlier in the decision making process and be scheduled at times that are convenient for families and coaches. Findings were used to inform a full-scale evaluation that is currently underway.

Usability of devices for self-injection: results of a formative study on a new disposable pen injector

This article presents a late-stage formative usability study of a pen-injector platform device. Such devices are used for the subcutaneous delivery of biopharmaceuticals, primarily for self-administration by the patient. The study was conducted with a broad user population, defined to represent user characteristics across a range of indications. The goals of the study were to confirm that the pen could be used without recurring patterns of use errors leading to hazardous situations, to evaluate the comprehension of the instructions for use (IFU), and to determine if training is necessary. In the study, a total of 36 participants in six groups (health care providers, caregivers, adolescents, diabetics with retinopathy, diabetics with neuropathy, and patients with arthritis) each read the IFU, prepared the device, and performed two simulated injections into an injection pad. Any use errors, near misses, or deviations from the IFU procedure were recorded. The overall success rate (injection completed by the participant without need for assistance) was 94% for the first and 100% for the second injection. Ninety-two percent of the participants reported that they felt confident using the device, 100% found the IFU helpful, and 75% found the device positively comfortable to use. Overall, a total average of 3.35 deviations and errors per user and injection were recorded (there were no near misses). Subtracting the errors without any potential for negative consequences for the injection or the user (trivial deviations), as well as those related to attaching and removing the pen needle (independent of the design of the pen itself), led to an average of 1.31 potentially relevant deviations per user and injection. It was concluded that the pen injector together with the IFU could be safely and efficiently used by all user groups without any training, and thus that the device and IFU in their current form are well suited for use in a range of specific applications.

The effect of medical device dose-memory functions on patients' adherence to treatment, confidence, and disease self-management

BACKGROUND

Adherence to treatment is an important issue in chronic disease management and an indicator of patients' ability to self-manage their condition and treatment. Some drug-dispensing and drug-delivery devices have been designed to support patients' medication-taking behavior by including dose-memory and combined dose-memory and dose-reminder functions, which electronically store, and visually display dose-history information, enabling the patient to review, monitor, and/or be actively reminded about their medication doses.

PURPOSE

This literature review explored the role and impact of these devices on patients' treatment adherence, confidence with, and self-management of their condition and treatment.

MATERIALS AND METHODS

A search of MEDLINE, Embase, and PsycINFO was performed to identify articles published in English from 2003-2013 that studied the effect of devices with dose-memory and combined dose-memory and dose-reminder functions on treatment adherence and users' (patients, health care professionals [HCPs], and caregivers) confidence, self-management behavior, and attitudes.

RESULTS

The database searches yielded 940 abstracts from which 13 articles met the inclusion criteria and were retained. Devices with dose-memory and combined dose-memory and dose-reminder functions were found to improve self-reported and electronically monitored treatment adherence in chronic conditions such as asthma, diabetes, and HIV. The ability of the devices to provide dose-history information and active medication reminders was considered valuable in disease management by patients, caregivers, and HCPs. The devices were found to enhance patients' confidence in, and motivation to manage their medication and condition, and help reduce forgotten or incorrect medication dosing.

CONCLUSION

The incorporation of dose-memory and combined dose-memory and dose-reminder functions in drug-delivery devices can improve patients' adherence, confidence, and self-management behavior. They can target non-intentional barriers to adherence and can provide a means of improving disease control and clinical outcomes, thereby offering clinical and economic value. This review highlights the importance of conducting further qualitative and quantitative research to further understand the value and impact of these types of devices on patients' long-term adherence to, and self-management of treatment.

Use of technology when assessing adherence to diabetes self-management behaviors

During the last several decades, a proliferation of sophisticated technology has taken place to facilitate diabetes self-management and improve health outcomes. Blood glucose monitors, insulin pumps, and continuous glucose monitors have significant data storage capacity, which can be used to summarize diabetes health management and outcomes. In the absence of technology errors or failures, and in the context of the multiple psychosocial factors associated with nonadherence, these data have the potential to elucidate diabetes care because they reflect actual patient behaviors. This review provides a summary of the diabetes adherence literature in the context of current American Diabetes Association Clinical Practice Recommendations with a focus on studies that have used objective methods (ie, data derived from technology) to assess diabetes care provider and patient adherence in the areas of glucose monitoring; insulin administration and antihyperglycemic medications; medical nutrition therapy; and physical activity.

Evaluation of a new durable insulin pen with memory function among people with diabetes and healthcare professionals

OBJECTIVES

The aim of the study was to evaluate durable insulin pens among people with diabetes (PwD) and healthcare professionals (HCPs), by comparing two durable insulin pens with memory function: NovoPen® 5 (NP5) and HumaPen® Memoir™ (HPM), and two durable insulin pens without memory function: HumaPen Luxura® (HPL) and ClikSTAR® (CS).

RESEARCH DESIGN AND METHODS

This cross-over, multicentre usability test was conducted in China, Germany and the UK. Participants evaluated all four pens in randomised order by performing handling and usability tasks related to everyday use during a face-to-face interview. Tasks, pens and preferences were rated by completing a questionnaire comprising of rating and open-ended questions.

RESULTS

NP5 was preferred by 51% of participants compared with HPM (22%, p < 0.01), HPL (12%, p < 0.01) and CS (15%, p < 0.01). Participants preferred the design of NP5 (in particular, appearance, length and robustness). Memory function for the two pens was rated equally by participants, but 54% of PwD rated NP5 as 'very easy' to learn to use versus 22% for HPM and significantly more HCPs found it 'very easy' to teach patients to use NP5 versus HPM (6-point rating scale; difference in mean score, p < 0.01). Substantially, more PwD would be confident in using NP5 (64%) compared with HPM (43%), HPL (49%) and CS (45%) (6-point rating scale; difference in mean score, p < 0.01).

CONCLUSIONS

NP5 was preferred by > 50% of PwD and HCPs. NP5 was more highly rated for design, memory function and ease of learning/teaching compared with HPM. Most PwD would be confident in using NP5 for administering daily insulin injections.

Evaluation of preference for a novel durable insulin pen with memory function among patients with diabetes and health care professionals

BACKGROUND

Improving adherence to insulin treatment for better glycemic control remains a challenge in the management of diabetes. New technological aids are required to help support adherence. This study evaluated preference for the NovoPen(®) 5 (NP5), a durable insulin pen with memory function, compared with the HumaPen Luxura(®) (HPL) among patients with diabetes and health care professionals.

METHODS

This crossover, multicenter usability study included insulin pen-experienced patients with diabetes and health care professionals treating patients with diabetes in Canada, China, and Germany. Participants evaluated NP5 and HPL in a randomized order by performing handling tasks in a usability test related to everyday use during a face-to-face interview. Tasks, pens, and preferences were assessed by completing a questionnaire comprised of rating and open-ended questions relating to confidence in everyday diabetes management.

RESULTS

Overall, 300 patients with diabetes and 150 health care professionals participated in the study. Significantly more participants preferred NP5 (81%) to HPL (18%) (P < 0.001). Also, 82% of patients with diabetes had more confidence in NP5 for managing their daily injections versus 11% with HPL (P < 0.001), and 7% had no preference. Memory function was most helpful in giving patients with diabetes confidence about when they last injected (63%), how much insulin they last injected (62%) and improving diabetes management (55%). Participants gave higher ratings to NP5 than to HPL on all parameters relating to performing an injection (ease of handling, satisfaction when using the pen, convenience of using the pen day-to-day, quality of the pen, and the extent to which the pen meets their needs; P < 0.05 for all comparisons).

CONCLUSION

NP5 was preferred to HPL by most participants. Significantly more patients with diabetes had more confidence for managing daily insulin injections when using NP5, the pen with a memory function.

Dose accuracy of a durable insulin pen with memory function, before and after simulated lifetime use and under stress conditions

OBJECTIVES

The objective of this study was to assess the dose accuracy of NovoPen® 5 in delivering low, medium and high doses of insulin before and after simulated lifetime use. A secondary objective was to evaluate the durability of the pen and its memory function under various stress conditions designed to simulate conditions that may be encountered in everyday use of an insulin pen.

RESEARCH DESIGN AND METHODS

All testing was conducted according to International Organization for Standardization guideline 11608-1, 2000 for pen injectors. Dose accuracy was measured for the delivery of 1 unit (U) (10 mg), 30 U (300 mg) and 60 U (600 mg) test medium in standard, cool and hot conditions and before and after simulated lifetime use. Dose accuracy was also tested after preconditioning in dry heat storage; cold storage; damp cyclical heat; shock, bump and vibration; free fall and after electrostatic charge and radiated field test. Memory function was tested under all temperature and physical conditions.

RESULTS

NovoPen 5 maintained dosing accuracy and memory function at minimum, medium and maximum doses in standard, cool and hot conditions, stress tests and simulated lifetime use. The pens remained intact and retained dosing accuracy and a working memory function at all doses after exposure to variations in temperature and after physical challenge.

CONCLUSIONS

NovoPen 5 was accurate at all doses tested and under various functionality tests. Its durable design ensured that the dose accuracy and memory function were retained under conditions of stress likely to be encountered in everyday use.

Safety and patient perception of an insulin pen with simple memory function for children and adolescents with type 1 diabetes--the REMIND study

OBJECTIVES

NovoPen Echo * is a durable pediatric insulin pen incorporating half-unit dosing starting at 0.5 units and a last-dose memory function. The REMIND † (Rating the Effects of Memory function in pediatric INsulin Devices) study primarily examined the safety of this new device by collecting data on technical complaints (TCs) related to adverse reactions (ARs) during use in a clinical setting.

METHODS

REMIND was an observational, multicenter study involving patients with type 1 diabetes on injection therapy, aged 2-18 years, from Canada, Finland, Israel and Sweden. Questionnaires and case report forms were completed at baseline and after using NovoPen Echo for 12-18 weeks.

RESULTS

In total, 358 patients participated and 315 completed. No serious ARs were reported. Three ARs related to TCs were reported, equated to one every 29 patient-years. Most patients found it 'easy' or 'somewhat easy' to read amount (99%) and hours lapsed (95%) since last dose using the memory function. The proportion of children self-injecting was significantly higher (71%) compared with those on previous device (66%, p=0.006). 80% of physicians answers reported they could train users in ≤10 minutes.

CONCLUSIONS

Only three device safety events were reported for NovoPen Echo. Physicians found it easy and quick to educate users. Patients/caregivers missed fewer injections and reported greater confidence in managing their insulin injections. As this was an observational study without controls or centralized laboratory testing, caution should be used in interpreting outcomes in glycemic control. Further studies are required to examine the effects of features such as memory function and half-unit dosing on HbA1c and hypoglycemia over a longer time period.

Needle with a novel attachment versus conventional screw-thread needles: a preference and ease-of-use test among children and adolescents with diabetes

BACKGROUND

This usability test investigated the overall preference and usability of the novel NovoTwist® insulin pen needle versus conventional screw-thread needles, when used with Next Generation FlexPen®, in children and adolescents with diabetes.

METHODS

This was an open-label, randomized, crossover usability test in children and adolescents with type 1 diabetes who administered insulin with an insulin pen. Test needles were NovoTwist and the participant's current screw-thread needle (or NovoFine® needle). Following instruction, participants attached the needle to Next Generation FlexPen, made an injection into a foam cushion, and detached the needle. This procedure was conducted three times with both needles in a random order. Responses to 13 questions on user experience with each needle (including overall preference, ease of attachment/detachment of needle/cap, handling, learning, confidence in attachment, and convenience of use) were subsequently recorded on a six-point rating scale (1 = very difficult; 6 = very easy).

RESULTS

Fifteen children aged ≥ 6 to ≤ 12 years and 15 adolescents aged ≥ 13 to ≤ 17 years participated in the test. A significantly higher proportion of children and adolescents (77%) indicated that they would prefer to use NovoTwist compared with screw-thread needles (p = .005). NovoTwist was preferred by most children and adolescents for overall ease of use (77%; p = .005), for ease of attachment (87%; p < .001) and detachment (83%; p < .001), and as the most appropriate needle to handle for daily injections (73%; p = .016). The mean rating for confidence in correct needle attachment was not significantly different between the two needle types. Seven out of eight parents of children who required assistance for their daily insulin injections stated that they would be "very likely" to allow their child to attach NovoTwist.

CONCLUSIONS

These factors may promote confidence in this needle, and thus in self-injecting, among younger patients and their parents.

What can we learn from patient-reported outcomes of insulin pen devices?

Although a variety of effective treatment options are available for patients with type 1 or type 2 diabetes, many patients in the United States have difficulty reaching their glycemic goals. Patient adherence to insulin therapy, which often involves self-administered subcutaneous injections of insulin using either a vial and syringe or an insulin pen device, is often poor. Various factors associated with the type of injection device have been shown to influence the rate of patient adherence to insulin therapy. This article reviews patient-reported outcome (PRO) evidence from pediatric and adult studies that compared insulin pen devices with vial and syringe use. In a majority of these cases, patients preferred the pen devices over vial and syringe, stating advantages such as ease of use, convenience, greater confidence in their ability to properly administer the drug, and a greater perceived social acceptance. The pens were considered less painful than syringes and were associated with less needle fear. In addition, PRO evidence has directed pen technology design, leading to development of more advanced insulin pen devices. By appreciating the correlation between adherence to insulin regimens and a patient's device preference, clinicians can make improved treatment recommendations to facilitate achievement and maintenance of glycemic targets.

Dose accuracy and durability of a durable insulin pen before and after simulated lifetime use

BACKGROUND AND OBJECTIVE

NovoPen Echo* is an insulin pen designed specifically for children and adolescents with diabetes. The pen combines half-unit dosing and a simple memory function that records the size of the last dose and the time in hours that has elapsed since last injection. Durability is an essential feature of durable insulin pens in order to ensure accuracy throughout the lifetime of the pen. This study was designed to assess dose accuracy and durability of NovoPen Echo before and after simulated lifetime use.

RESEARCH DESIGN AND METHODS

All testing was conducted according to International Organization for Standardization (ISO) guideline 11608-1 for pen injectors. Dose accuracy was measured for the delivery of 0.5 international units** (IU) (5 mg), 15 IU (150 mg) and 30 IU (300 mg) test medium before and after lifetime simulation under standard, cool and hot conditions. Functionality tests were also performed under a number of stress conditions including dry heat, cyclical temperature, vibration, free fall and electrostatic discharge.

RESULTS

The dose accuracy of NovoPen Echo meets the requirement stated in ISO 11608-1 for all three doses for all tests before and after lifetime simulation. The pens remained intact and retained dosing accuracy at all doses after exposure to variations in temperature and humidity and before and after physical challenge to simulate lifetime use.

CONCLUSIONS

The accuracy of NovoPen Echo was retained under conditions of stress likely to be encountered in everyday use due to its durable design.

Usability and preference evaluation of a prefilled insulin pen with a novel injection mechanism by people with diabetes and healthcare professionals

OBJECTIVE

This cross-over usability study assessed the perceptions of, and preference for, FT (FlexTouch*), a new prefilled insulin pen, compared with KP (KwikPen†) another widely available prefilled insulin pen, among people with diabetes and healthcare professionals (physicians and nurses).

RESEARCH DESIGN AND METHODS

Participants were randomly assigned to start with either FT or KP. Following instruction on how to operate the pen, the participant performed several injections at different doses into a foam cushion and then answered written questions on ease of use, confidence and preference.

RESULTS

Seventy-nine people with diabetes and 81 healthcare professionals (40 physicians and 41 nurses) took part. Overall, most respondents preferred using FT (86%) to KP (7%; p < 0.001), found FT (85%) the easier pen to use versus KP (4%; p < 0.001), and would recommend FT (88%) rather than KP (6%; p < 0.001). Ratings for FT were also significantly higher than for KP on questions relating to the injection process, including ease of depressing the push-button and ease of injecting at three dose levels (20 International Units [IU], 40 IU and 60 IU [p < 0.001 for all]). Significantly more respondents chose FT as the pen that gave them most confidence in correct and complete insulin delivery (73% vs. 6% for KP; p < 0.001).

CONCLUSIONS

FT was rated significantly higher (all p < 0.001) for ease of use and confidence, and was preferred over KP by people with diabetes, physicians and nurses. The features of FT may improve the insulin injection experience for a wide range of users. A limitation of the usability questionnaire employed in this study is that it did not assess the factors that influence preference. Additional analyses could be conducted using multivariate regression to help elucidate the features of FT that appeal to different users.

Insulin delivery by injection in children and adolescents with diabetes

Type 1 diabetes is treated with insulin, which has traditionally been delivered by vial and syringe. However, for many patients, dosing inaccuracy, pain, anxiety, inconvenience, and social acceptability present barriers to this method of administration (1-5). This has contributed to the increased popularity of alternative insulin delivery systems, including pen delivery devices (4, 6). Evidence suggests that discreet devices, such as insulin pens, facilitate adherence to intensive insulin therapy regimens, help improve lifestyle flexibility, and reduce injection pain compared with the conventional syringe-based regimens, as shown in studies in adults and adolescents (7). In addition, compared with the vial and syringe method of insulin administration, pens may provide more accurate dosing - which is particularly important in children - thereby improving short-term blood glucose control and potentially improving long-term outcomes (5, 8). Children, in particular, may benefit from insulin pens that are simple to use as adherence issues may be more evident in this patient group (9). Pens for insulin delivery in children with type 1 diabetes have been used for a long time in Europe, and have recently gained in popularity in many other places around the world (4, 10). Furthermore, the conventional vial and syringe method of insulin delivery is beginning to be considered as obsolete (11). Moreover, there is a continued drive to improve insulin pen technology, to refine and enhance the functionality and usability of these pens. However, despite recent advances in pen design and function, the selection of pens available especially for children is limited.