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

Quantifying Patient Capabilities and Setting the Stage for Future Development: Insights from a Sensor-Augmented Simulated Use Study with Pen Injectors

Background

While formative and summative usability testing is essential to confirm safe and effective product use, it may not be sufficient to comprehensively understand user capabilities and limitations in device interactions. Therefore, this research aims to quantify user handling forces for different device handling steps of pen injectors through sensor-augmented simulated use studies.

Research Design and methods

The study involved 46 participants who were divided into two groups: a healthy control group and a group of users with dexterity impairments. All participants were instructed to perform simulated handling steps using non-functional dummy devices equipped with force and torque sensors. Each handling step was performed twice: first at what participants considered a comfortable force level and then at their maximum force. The study then analyzed force data to investigate the impact of user characteristics and device geometry on force exertion during the different handling steps.

Results

The study demonstrates differences in the perceived comfortable and maximum force levels between the control and patient groups. These force levels decrease slightly with the user's age and level of dexterity impairment. Furthermore, the forces applied by the users are dependent on the geometry of the device and the holding pattern.

Conclusion

The results highlight the significance of sensor-augmented simulated use studies as a tool for providing quantitative insights into users' ability to exert force while handling self-injection devices. These data offer comprehensive insights that inform the definition of performance requirements and specifications for injection device design, thereby supporting the advancement of future self-injection devices.

Drug delivery improvements to enable a flexible care setting for monoclonal antibody medications in oncology - Analogue-based decision framework

INTRODUCTION

The substantial acceleration in healthcare spending together with the expenditures to manage the COVID19 pandemic demand drug delivery solutions that enable a flexible care setting for high-dose monoclonal antibodies (mAbs) in oncology.

AREAS COVERED

This expert opinion introduces an analogue-based framework applied to guide decision-making for associated product improvements for mAb medications that are either already authorized or in late-stage clinical development. The four pillars of this framework comprise (1) the drug delivery profile of current and emerging treatments in the market, (2) the needs and preferences of people treated with mAbs, (3) existing healthcare infrastructures, and (4) country-dependent reimbursement and procurement models. The following product optimization examples for mAb-based treatments are evaluated based on original research and review articles in the field: subcutaneous formulations, an established drug delivery modality to reduce parenteral dosing complexity, fixed-dose combinations, an emerging concept to complement combination therapy, and (connected) on-body delivery systems, an identified future opportunity to support dosing outside of a controlled healthcare institutional environment.

EXPERT OPINION

Leveraging existing synergies and learnings from other disease areas is a measure to reduce associated development and commercialization costs and thus to provide sustainable product offerings already at the initial launch of a medication.

Usability and effects on gait of an optimized schoolchildren backpack

BACKGROUND: Backpacks used by children is a global concern, because may cause musculoskeletal discomforts and pain. OBJECTIVE: The purpose of this study was to test the usability and effects on gait kinematics wearing the Trunkpack versus a traditional backpack and no backpack. METHODS: Twenty-four children (9 to 11 years old) from a public school participated in this study. The usability was evaluated after a five-week testing period using a questionnaire. Gait kinematics was evaluated (Vicon) when the children were wearing a standard backpack, an optimized backpack (Trunkpack), and no backpack. Both backpacks were loaded with 10% of body weight. RESULTS: Was observed more trunk, hip and knee flexion when the children carried a standard backpack in comparison using the Trunkpack and not carrying a backpack (p < 0.01). The Trunkpack and no backpack were similar. The Trunkpack was well accepted by the schoolchildren (81% positive responses); 79% liked the head opening, 88% liked the waist straps, and 83% liked the facility to put and take objects in and out of the Trunkpack. CONCLUSION: Trunkpack requires less postural adjustments during gait than a standard backpack. Gait kinematics with the Trunkpack was comparable to the gait without carrying a backpack.

Formative Study on the Wearability and Usability of a Large-Volume Patch Injector

Background

The subcutaneous self-administration of biologics using a single large-volume bolus dose requires novel large-volume patch injectors. However, the usability and wearability of such on-body devices has rarely been investigated thus far. Therefore, this formative simulated use experiment studies the overall handling and acceptability in terms of the size and weight of a novel 10 mL large-volume patch injector device platform.

Methods

Twenty-three participants, including patients and healthcare professionals, simulated two injections with the large-volume patch injector, each lasting 17 min. During the injections, the patient participants performed predefined movements and activities with the on-body devices. Perceived usability and wearability were assessed through observation by the moderator and participant-reported feedback using five-point Likert scales and open-ended interviews.

Results

All participants successfully completed the simulated injections. Only non-serious usability issues were identified. Users rated the device acceptability in terms of wearability and usability with high ratings.

Conclusion

The results suggest the safe and effective usage of a novel prefilled large-volume patch injector that enables the subcutaneous delivery of a single bolus dose of up to 10 mL with an injection duration of 15 min. The participants of the simulated use study successfully used the device regardless of the disease state, age, or body size and habitus.

User-Centric Approach to Specifying Technical Attributes of Drug Delivery Devices: Empirical Study of Autoinjector-Cap Removal Forces

PURPOSE

The subcutaneous delivery of biologics using pre-filled autoinjector devices continues to attract broad scholarly interests. However, research still lacks a detailed understanding of user perceptions as the basis for specifying the clinically relevant technical attributes of a device, such as the cap-removal force. Therefore, this article studies the ability of users to remove the autoinjector cap, as well as the effects of the cap-removal force and user characteristics on the perceived ease of decapping.

PATIENTS AND METHODS

Forty-two participants among patients, caregivers, and healthcare professionals removed the protective cap using non-functional devices with different target cap-removal forces between 25 N and 55 N. Data were collected on the ability of the users to effectively decap the device and their perceived ease of decapping. Linear regression was then applied to quantify the impact of the decapping force and patient characteristics on the perceived ease of decapping.

RESULTS

The participants of the study effectively decapped all autoinjector devices irrespective of age, sex, and dexterity impairments. Moreover, the study reveals that the perceived ease of decapping decreases significantly with increasing decapping force and participants' dexterity impairments.

CONCLUSION

The study provides initial empirical evidence on the ability of users to decap autoinjector devices and shows how increasing the cap-removal force and dexterity impairments reduce the perceived ease of decapping.

DropSafe safety pen needle helps to prevent accidental needlesticks after injections: results of a simulated clinical study

Background

Most needlestick injuries (NSIs) result from unsafe needle devices. DropSafe safety pen needle (SPN) was designed to help prevent such injuries before, during and after use through a built-in sharps injury prevention feature (SIPF).

Methods

A two-phase study was undertaken. For the pilot study, five non-healthcare users (NHCUs) performed evaluations. For the validation study, 30 evaluators comprising 10 healthcare professionals (HCPs) and 20 NHCUs performed evaluations. The aim of the study was to validate the performance of the SIPF of the SPN and to collect feedback from the evaluators on several aspects of the safety device. Participants performed simulated injections into an orange.

Results

The results show that no device failures were observed, and all manipulations were performed without a needlestick or without contact with the needle after injection. The safety feature of the SPN was activated successfully. It was shown that: the label on the seal was legible; the SPNs were easy to attach to the pen injector; injections were easy to perform; it was clear when safety feature was activated; removing the SPN from the injection pen was easy; and the written instructions were easy to understand.

Conclusion

The performance of the safety feature of SPN was successfully evaluated in terms of the prevention of NSIs. User feedback demonstrate that the device's ease of use, handling and instructions for use ensure safety and effectiveness of the SPN when used as intended.

A portfolio of biologic self-injection devices in rheumatology: how patient involvement in device design can improve treatment experience

Biologic drugs (e.g. anti-tumor necrosis factors) are effective treatments for multiple chronic inflammatory diseases including rheumatoid arthritis, axial spondyloarthritis, and psoriatic arthritis. Administration of biologic drugs is usually via subcutaneous self-injection, which provides many patient benefits compared to infusions including increased flexibility, reduced costs, and reduced caregiver burden. However, it is also associated with challenges such as needle phobia, patient treatment misconceptions and incorrect drug administration, and can be impacted by dexterity problems. Evidence suggests these problems, along with other drug administration challenges (e.g. patient forgetfulness, busy lifestyles, and polypharmacy), can reduce patient adherence to treatment. To combat these challenges, patient feedback has been used to develop a range of self-injection devices, including pre-filled syringes, pre-filled pens, and electronic injection devices. Providing different devices for drug administration gives patients the opportunity to choose a device that addresses the challenges they face as an individual. Research suggests involving patients in medical device development, providing patients with a choice of devices and enrolling individuals in patient support programs can empower patients to take control of their treatment journey. By providing a portfolio of self-injection devices, designed based on patient needs, patient experience will improve, potentially improving adherence and hence, long-term treatment outcomes.

How to prevent medication errors: a multidimensional scaling study to investigate the distinguishability between self-injection platform device variants

Background: The importance of subcutaneous drug delivery using self-injection devices based on common device platforms continues to grow. The resulting broad adoption of potentially look-alike or similar devices, however, raises concerns over limited device distinguishability and ensuing risk of medication errors. The objective of the study is thus to understand whether and how users effectively distinguish between self-injection device variants. Methods: Seventy-four patients, caregivers, and healthcare professionals were asked to pairwise rate the similarity of eight platform autoinjector variants. Multidimensional scaling was then used to convert individual ratings into spatial configurations and thereby identify the attributes that influence device distinguishability. Results: Five different device attributes driving distinguishability were identified. Three of the attributes corresponded to single design features (the label color, device size and device shape). Two device attributes (the aspect ratio and chromaticity) combined distinct yet interrelated design features. Conclusions: The study provides initial empirical evidence that users are able to distinguish between device variants and as to what device attributes drive distinguishability. Furthermore, the results highlight patterns in how various user groups distinguish between device variants. These patterns relate with the user group characteristics (e.g. age, sight or dexterity) and the context of device usage (e.g. healthcare professionals).

Formative usability evaluation of a fixed-dose pen-injector platform device

Background

This article for the first time presents a formative usability study of a fixed-dose pen injector platform device used for the subcutaneous delivery of biopharmaceuticals, primarily for self-administration by the patient. The study was conducted with a user population of both naïve and experienced users across a range of ages. The goals of the study were to evaluate whether users could use the devices safely and effectively relying on the instructions for use (IFU) for guidance, as well as to benchmark the device against another similar injector established in the market. Further objectives were to capture any usability issues and obtain participants’ subjective ratings on the properties and performance of both devices.

Methods

A total of 20 participants in three groups studied the IFU and performed simulated injections into an injection pad.

Results

All participants were able to use the device successfully. The device was well appreciated by all users with, maximum usability feedback scores reported by 90% or more on handling forces and device feedback, and by 85% or more on fit and grip of the device. The presence of clear audible and visible feedbacks upon successful loading of a dose and completion of injection was seen to be a significant improvement over the benchmark injector.

Conclusion

The observation that the platform device can be safely and efficiently used by all user groups provides confidence that the device and IFU in their current form will pass future summative testing in specific applications.

Usability of a new disposable autoinjector platform device: results of a formative study conducted with a broad user population

This article presents a late-stage formative usability study of an autoinjector platform device. Such devices are used for the subcutaneous delivery of biopharmaceuticals, primarily for self-administration by the patient. Previous usability work on autoinjectors reported in the literature has been specific to single indications. This study was instead conducted with a broad user population, defined to represent user characteristics across a range of indications. The goals of the study were to evaluate whether users could use the devices safely and effectively, and could understand the instructions for use (IFU) as well as the accompanying training. Further objectives were to capture any usability issues and to obtain participants’ subjective ratings on the IFU and training as well as the confidence and comfort in using the device. A total of 43 participants in 5 groups received training and performed simulated injections either into an injection pad or a mannequin. All participants were able to successfully use the device. The device was well appreciated by all users, with a reported degree of confidence in using the device of 98%, of user comfort of 93%, and of comprehensibility of IFU and training of 98%. These values are higher than other comparable results reported in the literature. The presence of both audible and visible feedback during injection was seen to be a significant factor contributing to injection success. The observation that the device can be safely and efficiently used by all tested user groups provides confidence that the device and IFU in their current form will pass future summative testing in specific applications.