Join Regulatory Compliance Associates® Inc. (RCA) and Nelson Labs at booth #902 during PDA Universe of Pre-Filled Syringes and Injection Devices Conference in Denver, CO March 22 – 27, 2026. The event will be held at the Gaylord Rockies Resort & Convention Center.
The PDA Universe of Pre‑Filled Syringes and Injection Devices Conference 2026 brings together global experts advancing the next generation of injectable drug delivery. Designed for professionals across formulation science, drug delivery, device development, and combination products, the conference spotlights how science, technology, and user experience converge to drive safer, smarter, and more sustainable solutions.
Event Participants
Jessica Schafersman – Poster Presentation
Title: The “Clinical Usability Study” for Prefilled-Syringe Combination Products: Purpose, Need, and How It Compares with Human Factors Validation and Clinical Safety Studies
Prefilled syringes are now the preferred presentation for many injectable biologics, including anti-VEGF agents for retinal disease. As combination products, they are evaluated from both a drug perspective (safety and clinical effectiveness) and a device perspective (safe use by intended users). When sponsors demonstrate through use-related risk analysis and comparison to a well-established reference syringe that no new risks are introduced, the U.S. Food and Drug Administration (FDA) may waive the need for a formal human factors validation study.
However, sponsors may still be asked late in development to conduct a “clinical usability study,” often without defined methodology or acceptance criteria. This case study evaluates the purpose and necessity of such studies by comparing them to human factors validation and clinical safety studies. Drawing on FDA guidance, international usability standards, and public regulatory records, it shows that clinical usability studies are not a defined study type and, as commonly conducted for simple syringes, do not meet the expectations of either model. The findings highlight both their limited value and the need for clearer regulatory expectations.
Learning Objectives
This case study examination has two aims. The first, expository, is to define and compare three study types that are routinely conflated: the human factors validation study, the clinical safety study, and the clinical usability study. The second, evaluative, is to argue that the clinical usability study, as commonly requested and executed for simple, well-characterized prefilled syringes, satisfies the formal expectations of neither established model it resembles, and that this is a remediable gap in guidance rather than an inherent feature of the problem.
