Formative and validation human factors studies of a new disposable prefilled injection device for subcutaneous delivery of acthar gel (repository corticotropin injection).

Background: The administration of repository corticotropin injection (Acthar Gel) via a single-dose prefilled injector (SelfJect) is intended to provide a simple, ergonomic alternative to traditional injection. Iterative human factors (HF) studies were conducted to identify potential use deviations and ensure appropriate device use.

Research design and methods: This article presents seven formative studies, a validation study (with prior pilot validation studies), and a supplemental validation study with participants including lay users, patients, caregivers, and healthcare providers. Participant interactions with SelfJect and the user interface were assessed. Use deviations, user preferences, and participants' ability to successfully complete tasks were evaluated to generate modifications to the device and user interface.

Results: In the validation study, 91% of participants successfully administered their first injection. Use errors were rare with simulated-use (6.9%) and knowledge-based (1.6%) testing. Use deviations were commonly attributed to experimental artifact or information oversight, and device warming had the most use errors (49% of participants), even with extensive testing and adjustments to the user interface.

Conclusions: SelfJect was able to be used in a safe and effective manner by the intended users. Iterative HF studies informed the mitigation of use-related risks to reduce the occurrence of use deviations during simulated use.