Evaluating the usability and safety of the semaglutide single-dose pen-injectors through summative (human factors) usability testing.

AIMS/INTRODUCTION: A single-dose, shield-activated pen-injector for each of the three approved dose variants (0.25, 0.5 and 1 mg) of once-weekly subcutaneous semaglutide has been developed to improve usability. This analysis presents findings from the summative usability testing process for the single-dose semaglutide pen-injectors, including the pen-injector four-pack cartons and instructions for use. MATERIALS AND METHODS: A total of 60 adults representing four user groups were included: patients with/without pen-injector experience, non-pharmacist healthcare professionals and pharmacists (each n = 15). Participants carried out four tasks: (i) pen-injector carton retrieval; (ii) first simulated injection; (iii) pen-injector retrieval; and (iv) second simulated injection. All participants carried out task 1, and patients and non-pharmacist healthcare professionals took part in tasks 2-4 (n = 45). The number and types of use errors, close calls and operational difficulties were evaluated, and participants subjectively rated the ease of each task on a scale of 1 (difficult) to 7 (easy). RESULTS: No potentially serious use errors and only one non-serious use error were reported. Eight participants committed use errors with no potential for harm, one participant committed an unclassified use error, one participant encountered a close call with no potential for harm and one participant experienced an operational difficulty. Mean ease-of-use ratings were 6.7 (task 1), 5.9 (task 2), 6.6 (task 3) and 6.9 (task 4). CONCLUSIONS: All three dose variants of the semaglutide single-dose pen-injector were considered easy to use (subjective feedback scores near 7) and not associated with any serious use errors, even when participants received no training before study participation.