Usability of the Ranibizumab 0.5 mg Prefilled Syringe: Human Factors Studies to Evaluate Critical Task Completion by Healthcare Professionals

Abstract

Both the simulated-use and actual-use usability studies yielded consistent data, showing that healthcare professionals are able to use the ranibizumab PFS by successfully performing all critical tasks involved in preparing and delivering an intravitreal injection. The simulated-use usability testing was sufficiently realistic and representative of real-world use, and was appropriate and preferred over actual-use usability testing for proper evaluation of the product user interface. Ranibizumab is approved in the United States to treat various eye conditions, including neovascular (wet) age-related macular degeneration, macular edema following retinal vein occlusion, diabetic macular edema, diabetic retinopathy, and myopic choroidal neovascularization. It is administered as an injection into the eye once a month, and is available in a vial from which medication needs to be withdrawn using a standard syringe with a 19-gauge filter needle. The filter needle is then replaced by a smaller gauge needle for the intravitreal injection. The recent U.S. Food and Drug Administration approval of a 0.5 mg ranibizumab prefilled syringe eliminates the need for withdrawing medication from a vial and changing needles prior to use. The studies described in this report assessed the usability of the ranibizumab prefilled syringe by retina specialists and ophthalmic medical personnel in simulated- and actual-use settings. Twelve tasks that included unpacking, preparing, and properly administering the prefilled syringe for intravitreal injection were evaluated by a study assessor. Task performances were evaluated for use errors, close calls, and operational difficulties. Participants successfully performed all the tasks without any critical errors in both simulated-use and actual-use human factors usability studies, and most participants found the syringe to be "Easy" or "Very Easy" to use.

Evaluation of a Novel Prefilled Syringe Concept for Ophthalmic Applications: A Formative Human Factors Study

“…Notably, tip cap inspection was not considered an Essential or Safety Critical Task in formative or summative testing of the ranibizumab PFS (26). Most of the remaining use errors were related to lack of frequent experience with PFS devices for IVI, transference behaviors from existing products, or incorrect technique around the IVI procedure itself.…”

“…Some of these complications have been associated with medication preparation (8)(9)(10)(11)(12), and particular concern has been raised regarding introduction of silicone oil (SO) droplets into the eye from silicone-lubricated syringes used during the procedure (13-25), especially when conventional hypodermic syringes are used. These issues have spurred the development of delivery devices intentionally designed for IVI, such as the recently approved ranibizumab prefilled syringe (PFS) (26). Use of PFSs to deliver IVIs offers the potential to reduce injection time, lower the risk of contamination, endophthalmitis, intraocular air bubbles, and SO droplets, and increase dosing accuracy (8,(27)(28)(29)(30)(31)(32)(33)(34).…”

<p>Prefilled syringes for intravitreal drug delivery</p>

“…Therefore, using the PFS, the physician simply removes the syringe cap, attaches the injection needle, and adjusts the dose prior to administration. Retina specialists and ophthalmic medical personnel have successfully performed both simulated-use and actual-use usability studies (with the PFS) with reported ease and without any critical errors 14. Reduction in these steps in the administration of intravitreal injections comes with some advantages which are detailed in the following sections.…”