Autoinjectors for large-volume subcutaneous drug delivery: a review of current research and future directions.

Introduction: The growing interest in subcutaneous delivery of larger single-dose volumes using handheld autoinjectors raises questions about the feasible upper limits for injection volume and rate. This review critically evaluates the literature on subcutaneous administration with dose volumes greater than 1.0 mL. In so doing, it examines how previous work has addressed limitations and considerations for designing and developing large-volume autoinjectors.

Areas covered: This article synthesizes 31 studies on large-volume subcutaneous delivery through a systematic review process and structures their findings based on three themes critical to developing large-volume autoinjectors: injection tolerability, suitability for self-administration, and pharmacokinetic equivalence with existing dosing options. This review highlights the answers provided by previous studies and identifies promising avenues for future research.

Expert opinion: This review finds that the literature supports the feasibility of delivering single large-dose subcutaneous volumes, providing a foundation for large-volume autoinjectors. Moreover, the review guides future research to address questions within and across themes critical to large-volume autoinjector development, helping to provide health-care professionals and patients with more effective and convenient dosing options.