A review of reusable insulin pens and features of TouStar-a new reusable pen with a dedicated cartridge.

BACKGROUND: Since the introduction of the first reusable insulin pen, the advancement in the design of these pens is still ongoing to develop a safe, more efficacious, less painful, and easy to use insulin pen device. MAIN BODY: Possible errors in insulin delivery can occur at any stage of insulin delivery such as during the prescription stage, dispensing stage, or at administration stage. Mismatch of the insulin pen and cartridge is not uncommon and is a potential risk for individuals with diabetes due to serious consequences associated with incorrect insulin usage. The similarities in insulin cartridges of different manufacturers with regard to color and product names could lead to mix-up of insulin pens and cartridges. These unmet needs have led to the ongoing search for developing insulin pens that can address these errors and provide more efficacious and safer choices for patients with diabetes. CONCLUSION: This review provides an overview of currently available reusable pens in the market and highlights the features of TouStar®, a new reusable pen with a dedicated cartridge intended to mitigate the risk of mismatch of the cartridge.

Dialing torque preferences of people with diabetes when using insulin pens: a pilot study.

INTRODUCTION: Ergonomic dialing torque may enhance safety and comfort when setting doses with insulin pens. Limited data are available on the correlation of dialing torque and dialing comfort. METHODS: Three studies were performed with SoloSTAR(®) (SS; Sanofi), FlexPen(®) (FP; Novo Nordisk), KwikPen(®) (KP; Eli Lilly) and FlexTouch(®) (FT; Novo Nordisk) pens. Dialing behavior was examined with 20 pen-experienced people with diabetes. Participants dialed up to the maximum dose and back down to "zero" with each pen. Hand and pen movements were recorded by video camera and rotational speeds and angles calculated for each pen. In a laboratory study, dialing torque was measured discontinuously at a speed of 120°/s, reflecting typical patient behavior. Sixteen pen-experienced people with diabetes participated in a pilot preference study. Using a Likert scale, subjective dialing comfort rankings and ratings were obtained for each pen type and matched to their dialing torque. SS, FP, KP, and FT1 were investigated at 0-20 U each and at 60-80 U for FT2. RESULTS: SS was ranked most comfortable for up-dialing by 8 and down-dialing by 6 of the 16 participants, respectively; FP, 5 and 8; FT1, 2 and 1; and KP, 1 and 1. FT2 was ranked least comfortable by 12 and 10 participants. Comfort for up- and down-dialing was rated "very comfortable" for SS by 15 participants each, followed by FP (12 and 14), KP (10 each), and FT1 (9 and 7); FT2 was rated "less" or "not" comfortable by 10 and 11 people, respectively. CONCLUSION: In this pilot study, subjective ratings of dialing comfort for different insulin pens by participants appear to concur with previous laboratory dialing torque study results. There appears to be a "torque comfort zone." Torques above 50 N mm reduced subjective handling comfort. Further, larger scale studies are needed to establish that dialing torque affects pen users' comfort.

Dose accuracy and injection force of different insulin glargine pens.

BACKGROUND: Dose accuracy and injection force, representing key parameters of insulin pens, were determined for three pens delivering insulin glargine-based copies, Pen Royale (WR) and DispoPen (WD) for Glaritus® (Wockhardt) and GanLee Pen (GL) for Basalin® (Gan & Lee), compared with pens of the originator, ClikSTAR® (CS) and SoloSTAR® (SS) for Lantus® (Sanofi). METHODS: Using the weighing procedure recommended by DIN EN ISO 11608-1:2000, dose accuracy was evaluated based on nonrandomized delivery of low (5 U), mid (30 U), and high (60 U) dosage levels. Injection force was measured by dispensing the maximum dose of insulin (60 U for the GL, WR, and WD; 80 U for the SS and CS) at dose speeds of 6 and 10 U/s. RESULTS: All tested pens delivered comparable average doses within the DIN EN ISO 11608-1:2000 limits at all dosage levels. The GL revealed a higher coefficient of variation (CV) at 5 U, and the WR and WD had higher CVs at all dosage levels compared with the CS and SS. Injection force was higher for the WR, WD, and GL compared with the CS and SS at both dose speeds. In contrast to the CS and SS with an end-of-content feature, doses exceeding the remaining insulin could be dialed with the WR, GL, and WD and, apparently, dispensed with the WD. CONCLUSIONS: All pens fulfilled the dose accuracy requirements defined by DIN EN ISO 11608-1:2000 standards at all three dosage levels, with the WR, WD, and GL showing higher dosage variability and injection force compared with the SS and CS. Thus, the devices that deliver insulin glargine copies show different performance characteristics compared with the originator.

Dose accuracy of the ClikSTAR, NovoPen 4, and Luxura insulin pens: results of laboratory and field studies.

BACKGROUND: A high dosing accuracy is needed to maintain normal glycemia in patients with diabetes. This study investigated the dose accuracy of the commonly used reusable insulin pens ClikSTAR®, NovoPen® 4, and Luxura®. METHODS: Pens were tested in a laboratory setting by one trained technician who delivered four doses of 30 U from each of 15 pens per pen model (a total of 60 doses from each pen model). Pens were also tested in a simulated clinical setting by 48 people with diabetes. Each participant delivered 27 doses: three doses of 30 U from each of three pens per pen model. Overall, the technician delivered 180 doses and the participants 1296 doses. RESULTS: All pens met the tolerance limits defined by the German edition of the International Standardization Organization (ISO) 11608-1:2000 standard [30 ± 1.5 U (28.5-31.5 U)]. All doses were delivered within the limits proposed by the ISO, except for two doses with Luxura in the clinical setting. In laboratory testing, the mean dose delivered by ClikSTAR (29.69 U) or Luxura (29.89 U) was less than the expected 30 U and significantly less than the mean dose delivered by NovoPen 4 (30.04 U; p < .001 for both comparisons). Similar results were observed in the simulated clinical setting. NovoPen 4 had the greatest variance in laboratory testing but the least in the simulated clinical setting. CONCLUSIONS: This study demonstrates comparable dose accuracy and variability of the ClikSTAR, Luxura, and NovoPen 4 insulin pens. The slight differences in mean doses between pens are unlikely to be clinically significant.

Injection force of reusable insulin pens: Novopen 4, Lilly Luxura, Berlipen, and ClikSTAR.

BACKGROUND: Insulin pen devices are used by approximately half of insulin users worldwide. The injection force of insulin pens is a key element in their design. This study aimed to demonstrate that the sanofi-aventis reusable ClikSTAR® (CS) pen has an improved injection force over existing insulin pens. METHODS: The injection force of four reusable insulin pens--Novopen® 4 (NP4; Novo Nordisk), Luxura® (LL; Eli Lilly and Co.), Berlipen® (BP; Haselmeier GmbH), and CS (sanofi-aventis)--was tested in a laboratory setting. Injection force was tested using two methods: six dispense rates between 6 and 24.66 U/s (constant volume flow rate) and constant button speeds of 4 and 8 mm/s. RESULTS: The CS required a lower mean injection force versus NP4, LL, and BP at both doses and all dispense rates. Mean injection force was 45%, 126%, and 60% higher for NP4, LL, and BP versus CS, respectively (p < .05 for each of the comparisons), for a flow rate of 6 U/s at 60 U dose. Mean injection force in all pens increased with the dispense rate, but the injection force remained significantly lower for CS versus all other pens (p < .05). The injection force for CS was significantly lower for 60 U at 10 and 17.03 U/s than for 80 U. CONCLUSIONS: The study demonstrated that CS pens require a lower injection force at a wide range of different injection speeds than other reusable insulin pens. This is an important benefit for patients with diabetes, especially those with limited dexterity.

Dose accuracy of SoloSTAR and FlexPen as assessed in a clinical setting.

AIMS: This study aimed to compare the accuracy of SoloSTAR(sanofi-aventis, Paris, France) and FlexPen (Novo Nordisk, Bagsvaerd, Denmark) to deliver doses of insulin when used by insulin/device-naive people attending a local healthcare practice. METHODS: For the determination of dose accuracy, SoloSTAR containing insulin glargine (lot 672) and FlexPen containing insulin aspart (lot SH70557) were used for all tests. The participants were given instruction by an independent monitor on how to use the pens. To be consistent, users were trained to hold the pens in situ for 10 s at the end of injection to ensure that the full dose was injected. Forty-eight subjects performed three dose deliveries of 20 units (into a sponge) with each pen type. The method of injecting into a sponge aimed to mimic real-life practice; this approach is commonly used to ensure the patient has a correct injection technique before the patient self-administers the injection. RESULTS: The delivery (n = 144) of individual doses of 20 units was not statistically different (P = 0.187) between SoloSTAR (mean +/- SD, 19.75 +/- 0.30 units) and FlexPen (19.80 +/- 0.33 units). In total, 2% of doses from both devices were <19 units; 98% were within 19-21 units. CONCLUSIONS: Both SoloSTAR and FlexPen were similarly accurate when used by device-naive subjects to deliver 20-unit doses of insulin. This is likely to have beneficial clinical effects in terms of glycemic control, as well as improved patient confidence that insulin pens accurately deliver doses of insulin.