Evaluation of injection force of three insulin delivery pens

Consensus on Choice of Insulin Pen Devices in Routine Clinical Practice in India

Although insulin delivery devices are widely used by the patients, there is a paucity of published guidelines to help professionals manage their patients in insulin therapies. To provide simple and easily implementable guidelines to health care physicians on the choice of insulin delivery devices in routine clinical practice, experts in diabetes gathered together and discussed the recommendations at the National insulin Summit 2018. An ideal insulin delivery device should accurately deliver the prescribed dose of insulin and be easy to use. Recommendations are: (1) insulin should be initiated by using an insulin device if the patient seems to discontinue insulin therapy. (2) Pen devices offer accurate dosing than a syringe and vial and are associated with cost savings in the long term. (3) Switching over from syringes and vial to disposable pen devices improves adherence. (4) FlexPen^® offers better accuracy, and it requires lower dose force and injection force than SoloStar^® and KwikPen^® (5). Durable delivery pens such as NovoPen^® 4 maintain accuracy and low dose force compared with vials and syringes. (6) One pen should be used by only one patient. (7) Regular counseling on the proper use of the pen device is required regularly. This consensus-based recommendation is a useful reference tool for health care practitioners to initiate insulin therapy in patients with diabetes by using the appropriate insulin pen device.

Clinical characteristics and patient treatment satisfaction with Humalog U-200 in patients with type 2 diabetes mellitus: an observational study

Background: There are limited data on the real-world evidence of Humalog 200 units/ml KwikPen (U-200) insulin. We assessed the use of U-200 insulin in UK routine clinical practice to provide information on clinical characteristics, treatment satisfaction and short-term clinical outcomes. Methods: Nine patients with type 2 diabetes who initiated U-200 in secondary care and a further 12 identified from primary care electronic database were enrolled. A treatment satisfaction questionnaire was administered to the 19 secondary care patients. Follow-up data on clinical parameters were collected at 3 and 6 months following initial U-200 insulin administration and the data were used to assess changes in clinical outcomes from baseline. Results: Secondary care patients had a mean age 60 ± 11 years, mean HbA1c of 8.6% ± 1.3% and a mean BMI of 39.7 ± 5.3 kg/m² at baseline. Primary care database patients had a mean age 57 ± 13 years, mean HbA1c 10.3% ± 1.7 and a mean BMI 42.3 ± 3.8 kg/m². The nine participants' responses to the questionnaire suggested a high preference for U-200 over a previous mealtime insulin pen (PMIP). On average, the patients agreed that U-200 was quicker to inject, had a better controlled home blood glucose reading and less discomfort at the injection site compared to a PMIP. Patients were willing to continue with their U-200 treatment. No significant HbA1c reduction was observed at 3 months in the secondary care group (-0.5%), but marked significant reduction in HbA1c was seen at 3 months in the primary care dataset to (-2.8%; p < .0004). There was also some suggestion of weight loss in both the secondary and primary care groups. Conclusion: Humalog U-200 insulin users were comprised mainly of older patients with diabetes complications and high HbA1c levels at the time of U-200 initiation. Overall, U-200 improved patients' satisfaction with diabetes treatment and short-term metabolic outcomes.

A randomized, open-label, comparative, crossover trial on preference, efficacy, and safety profiles of lispro insulin u-100 versus concentrated lispro insulin u-200 in patients with type 2 diabetes mellitus: a possible contribution to greater treatment adherence

BACKGROUND

Several outstanding pharmacological advances making innovative drugs sophisticateddevices available during the last few years. Nevertheless too many patients still disappointingly fail to meetthe metabolic targets suggested by current guidelines. Incorrect insulin administration techniques may greatly affect metabolic control in T2DM people. The aim of our study was to compare glycemic control associated with a concentrated insulin analog preparation (U-200 lispro) in people with T2DM to the one observed with standard U-100 lispro. The secondary endpoint of our study was patients' preference and performance ratings of U-200 lispro.

METHODS

126 patients with T2DM were enrolled. They were also assessed for limited joint mobility syndrome (LJMS),defined as limitation in at least two anatomical areas of the dominant upper extremity. After a 4-weekstructured insulin injection education period. Half of them were randomized to U-100 lispro, half to U-200 and after 12 weeks they were switched to the other preparation for 12 weeks. At the end a questionnaire was also administered to investigate patient preference.

RESULTS

No significant variation in fasting blood glucose, HbA1c, severe or mild hypoglycemic rate and daily fast-acting insulin analog dose was observed with U-100 lispro while U-200 lispro treatment was associated with a significant improvement of all the above mentioned parameters and with around 20% decrease in insulin requirement. Moreover patients' answers to the questionnaire pointed out a higher preference for U-200 lispro for continuing treatment due to fewer difficulties completing injection.

DISCUSSION

The explanation of better metabolic results with the U-200 device might be the lower inner piston inertia and volume and shorter duration of a complete injection.

CONCLUSIONS

Checking for LJIMS before insulin prescription could be adopted as a standard practiceaimed at choosing the most suitable device for patient's specific characteristics and abilities. The use of U-200 lispro might improve treatment adherence and metabolic control. This would also result intocost reduction by saving about half the amount of pens per year and of time spent to both fill prescriptionand dump the pharmacy.

FlexTouch® for the delivery of insulin: technical attributes and perception among patients and healthcare professionals

Insulin injection pens have improved the ease and convenience of administering insulin for people with diabetes. This article reviews the data on a new prefilled insulin pen, FlexTouch®. FlexTouch has a novel injection mechanism with no push-button extension and a lower injection force than other prefilled pens, and other features including an end-of-dose click; a large dose display; color-coded pens to distinguish different insulin types; an ergonomic design; and compatibility with both NovoTwist® needles and most screw-thread needles. FlexTouch has been demonstrated to deliver insulin consistently and accurately at minimum, half-maximum and maximum doses. In usability studies recruiting patients and healthcare professionals, FlexTouch was easier to use and instilled more confidence than other prefilled pens, and was preferred to other prefilled pens. FlexTouch was also found to be easier to use and was preferred for learning and teaching to use.

Addressing barriers to insulin therapy: the role of insulin pens

Despite the fundamental role of insulin therapy in diabetes management, many patients and some clinicians may resist insulin initiation due to concerns about its complexity or a general resistance to injections. Many patients' concerns about insulin initiation may stem from perceptions about the pain and inconvenience of using vials and syringes for delivering insulin. However, insulin pen devices offer an easier method for insulin administration that is more accurate, less painful, and more discreet compared with vials and syringes. Advances in insulin pen technology have enhanced their utility by increasing their accuracy, reducing the injection force required, and incorporating mechanisms to store the dose, time, and date of previous insulin injections. Substantial evidence demonstrates that insulin pen devices are preferred by both patients and clinicians and have the potential to improve adherence, enhance quality of life, reduce the risk of hyperglycemia, and decrease costs. Ultimately, the advantages of insulin pens may reduce resistance to initiating and adhering to insulin therapy. Because insulin pens are underused in the United states compared with in other countries, it is critical that clinicians understand the potential benefits of insulin pens and communicate them to their patients.

A prefilled insulin pen with a novel injection mechanism and a lower injection force than other prefilled insulin pens

BACKGROUND

FlexTouch(®) (Novo Nordisk A/S, Bagsvaerd, Denmark) is a new prefilled insulin pen for people with diabetes, with a novel injection mechanism and no push-button extension at any dose setting. This study compared the injection force of FlexTouch with that of SoloStar(®) (sanofi-aventis, Paris, France) and KwikPen(®) (Eli Lilly & Co., Indianapolis, IN).

METHODS

Injection force was measured with the manufacturers' recommended needle attached to each pen (NovoFine(®) [Novo Nordisk] 32-gauge tip extra thin wall 6 mm needle for FlexTouch and BD [Franklin Lakes, NJ] MicroFine™ 31-gauge 5 mm needle for SoloStar and KwikPen) during injection of the maximum dose (60 IU for KwikPen and 80 IU for FlexTouch and SoloStar). Injection was performed at three different constant push-button speeds.

RESULTS

FlexTouch had a significantly (P<0.0001) lower injection force than SoloStar and KwikPen at all injection speeds. The mean±SD injection force of FlexTouch was 5.1±0.5 N. At 4, 6, and 8 mm/s push-button speeds, the injection force of SoloStar was 13.5±2.1, 19.1±1.9, and 26.9±2.4 N, respectively, and the injection force of KwikPen was 14.5±1.9, 20.9±1.4, and 28.2±1.4 N, respectively.

CONCLUSIONS

The injection mechanism of FlexTouch means that insulin injection is driven by a torque spring and not the thumb pressure of the user. This results in a 62-82% lower injection force with FlexTouch than other prefilled insulin pens.

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.

Needle with a novel attachment versus conventional screw-thread needles: a preference and usability test among adults with diabetes and impaired manual dexterity

BACKGROUND

NovoTwist(®) (Novo Nordisk A/S, Bagsværd, Denmark) is an insulin pen needle that features a novel attachment and detachment system. The aim of this test was to assess overall preference and handling of NovoTwist compared with conventional screw-thread needles in people with type 1 or type 2 diabetes.

METHODS

One hundred twenty adults with type 1 or type 2 diabetes and manual dexterity dysfunction who were currently self-injecting with an insulin pen were included in this open-label, randomized, crossover test. Participants were stratified according to the impact that manual dexterity problems had on their ability to inject insulin (1 = no effect at all; 4 = a lot), and those rated as 1 were excluded from subanalyses because of low numbers. Following instruction, participants attached the needle to Next Generation FlexPen(®) (Novo Nordisk A/S), made an injection into a foam cushion, and detached the needle; this process was repeated three times with NovoTwist and the participant's current screw-thread needle (or NovoFine(®) [Novo Nordisk A/S]) in a random order. Responses to questions on user experience with each needle were subsequently recorded on a 6-point rating scale (1 = very difficult; 6 = very easy).

RESULTS

Significantly more respondents had a preference for NovoTwist (79%) compared with the conventional screw-thread needles (21%, P < 0.001). Significantly more respondents preferred NovoTwist for both ease of attachment (80%, P < 0.001) and ease of detachment (74%, P < 0.001). Most respondents found NovoTwist the most appropriate needle for performing everyday injections (71%, P < 0.001).

CONCLUSIONS

Such preference by patients has a positive impact on the treatment of diabetes as NovoTwist may alleviate the burden of performing everyday injections through its ease of use.

Injection force of SoloSTAR® compared with other disposable insulin pen devices at constant volume flow rates

BACKGROUND

Injection force is a particularly important practical aspect of therapy for patients with diabetes, especially those who have dexterity problems. This laboratory-based study compared the injection force of the SoloSTAR® insulin pen (SoloSTAR; sanofi-aventis) versus other available disposable pens at injection speeds based on the delivered volume of insulin released at the needle.

METHOD

Four different prefilled disposable pens were tested: SoloSTAR containing insulin glargine; FlexPen® and the Next Generation FlexPen® (NGFP) (Novo Nordisk), both containing insulin detemir; and KwikPen® containing insulin lispro (Eli Lilly). All pens were investigated using the maximum dispense volume for each pen type [80 units (U) for SoloSTAR; 60 U for the other pens], from the free needle tip dispensing into a beaker. Twenty pens of each type were fitted with the recommended needles and tested at two dose speeds (6 and 10 U/s); each pen was tested twice.

RESULTS

Mean plateau injection force and maximum injection force were consistently lower with SoloSTAR compared with FlexPen, NGFP, and KwikPen at both injection speeds tested. An injection speed of 10 U/s was associated with higher injection force compared with 6 U/s for all the pens tested (p < .001).

CONCLUSIONS

SoloSTAR stands out because of its low injection force, even when compared with newer insulin pen devices such as the KwikPen and NGFP. This may enable patients, especially those with dexterity problems, to administer insulin more easily and improve management of their diabetes.

A clinical and health economic review of a prefilled insulin pen

OBJECTIVE

Several different durable or disposable insulin pen delivery devices are currently available, and newer, improved devices are being introduced. One prefilled insulin device, FlexPen (FP), has recently been improved (known as the Next Generation FlexPen (NGFP) in Europe or the improved FlexPen in the United States). The aim of this review is to summarize the clinical and health economic data of FP and its modified version.

METHODS

Relevant clinical and health economic terms relating to insulin pens were used to search Medline for studies and other publications involving FP and NGFP.

RESULTS

Sixteen publications investigating FP and/or the NGFP were identified. Patients prefer FP and are more confident with its use in comparison to vial/syringe insulin administration: in a study of 105 patients with type 1 or type 2 diabetes, 85% of patients found FP to be more discreet for use in public than a syringe, 74% of patients found FP to be easier to use overall and 82% of patients had more confidence with setting the correct dose with FP. Four publications investigated the dosing accuracy of FP or NGFP: all studies found the study doses for both were within ISO-specified limits. Pharmacoeconomic issues with insulin pen devices were identified in four papers, and switching to FP from vial/syringe was found to increase treatment adherence from 59% to 68% (p < 0.01), as measured by medication possession ratio. Switching to FP is also a cost-effective option for patients. Mean all-cause annual treatment (-$1748/patient, p < 0.01), hypoglycaemia-attributable costs (-$908/patient, p < 0.01), and other diabetes-attributable costs (-$643/patient, p < 0.01) were reduced following the switch from vial/syringe.

CONCLUSIONS

Some limitations of traditional insulin administration devices can be overcome with insulin pen devices. FP is a prefilled disposable pen that has been modified to further improve characteristics beneficial to patient insulin administration.

An evaluation of prefilled insulin pens: a focus on the Next Generation FlexPen(®)

Insulin pen delivery systems are preferred by patients over the traditional vial and syringe method for insulin delivery because they are simple and easy to use, improve confidence in dosing insulin, and have less interference with activities and improved discretion with use. Insulin manufacturers have made numerous improvements to their first marketed pen devices and are now introducing their next generation of devices. Design modifications to the newest generation of prefilled insulin pen devices are intended to improve the ease of use and safety and continue to positively impact adherence to insulin. This review focuses on the Next Generation FlexPen(®) with regard to design considerations to reduce injection force, improve accuracy and ease of use, and evaluate the preference of patient and health-care provider compared with other disposable, prefilled insulin pen devices.

Practical aspects of insulin pen devices

Insulin pen devices have several advantages over the traditional vial-and-syringe method of insulin delivery, including improved patient satisfaction and adherence, greater ease of use, superior accuracy for delivering small doses of insulin, greater social acceptability, and less reported injection pain. In recent years, pens have become increasingly user-friendly, and some models are highly intuitive to use, requiring little or no instruction. Despite this progress, uptake of these devices in the United States has not matched that in many other areas of the world. There is a need for improved awareness of the current characteristics of insulin pen devices among United States health care professionals. Knowledge of the design improvements that have been incorporated into pens, both to address patient needs and as a result of the improved technology behind the device mechanics, is essential to promoting the use of insulin pen devices. This review highlights some of the practical aspects of pen use and discusses the factors to be considered when selecting among different insulin pens.

Engineering study comparing injection force and dose accuracy between two prefilled insulin injection pens

OBJECTIVE

This study compared injection force (measured by glide force [GF] and glide force variability [GFV]) and dosing accuracy of the Humalog KwikPen * (prefilled insulin lispro [Humalog dagger] pen, Eli Lilly and Company, Indianapolis, IN) and the Next Generation FlexPen double dagger (prefilled insulin aspart [NovoRapid section sign] pen, Novo Nordisk A/S, Bagsvaerd, Denmark). * Humalog KwikPen is a registered trademark of Eli Lilly and Company, Indianapolis, IN, USA. dagger Humalog is a registered trademark of Eli Lilly and Company, Indianapolis, IN, USA. double dagger FlexPen is a registered trademark of Novo Nordisk A/S, Bagsvaerd, Denmark. section sign NovoRapid is a registered trademark of Novo Nordisk A/S, Bagsvaerd, Denmark.

RESEARCH DESIGN AND METHODS

A total of 100 prefilled insulin pens (50 insulin lispro pens, 50 insulin aspart pens) were tested using two dose sizes (30 U and 60 U). In all, 50 devices (25 of each type) were tested at 10 U/s dosing speed and 50 were tested at 6.6 U/s. Devices were used per manufacturer instructions. Dose accuracy (represented as absolute dose error %), maximum and average GF, and GFV data were automatically collected by the test system for all datasets (dose size/dosing speed/device type). The test system controlled for potential dosing errors.

RESULTS

The insulin lispro pen demonstrated a significantly lower median maximum GF at both dosing speeds: (2.83 vs. 3.92 lbs [30 U] and 3.00 vs. 4.14 lbs [60 U]) at 10 U/s; (1.85 vs. 2.93 lbs [30 U] and 2.14 vs. 3.02 lbs [60 U]) at 6.6 U/s, all p < 0.0001. For all datasets, the median GFV was significantly lower for the insulin lispro pen, p < 0.0001. Median dose error was comparable between device types when tested at 10 U/s dosing speed; however, at 6.6 U/s, the median dose error was significantly lower for insulin lispro pen compared to insulin aspart pen (0.47 vs. 0.67% [30 U] and 0.50 vs. 0.78% [60 U], both p < 0.05).

CONCLUSIONS

The insulin lispro pen had significantly lower median GF and GFV compared with insulin aspart pen when tested at two dose sizes and two dosing speeds. Median dose error was similar between the device types at the 10 U/s dosing speed, but median dose error was significantly lower for the insulin lispro pen at the 6.6 U/s dosing speed. A limitation of this study was that it was executed as an open label study.

An analysis of patient acceptance and safety of a prefilled insulin injection device

This article summarizes and interprets the findings of Carter and colleagues in this issue of Journal of Diabetes Science and Technology, a study of the real world use of a prefilled insulin pen device. In this observational study, people with type 1 and type 2 diabetes rated their experience with the SoloSTAR pen device after 6-10 weeks of use. Data on patient satisfaction, product technical complaints, and adverse effects were reported. Randomized, controlled trials are needed that compare the various pen devices and the vial/syringe in terms of accuracy of dosing, adherence to therapy, and ease of use (including patient perception of injection force required) to assess whether a particular method of insulin delivery or pen delivery device provides a clinical advantage over another.