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The EyeFlowCell: Development of a 3D-Printed Dissolution Test Setup for Intravitreal Dosage Forms
Tobias Auel1, Linus Großmann1, Lukas Schulig2
1Center of Drug Absorption and Transport, Department of Biopharmaceutics and Pharmaceutical Technology, Institute of Pharmacy, University of Greifswald, 17489 Greifswald, Germany.
Pharmaceutics
|September 28, 2021
Summary
A new EyeFlowCell (EFC) model using polyacrylamide gel better simulates intravitreal drug release than standard methods. This gel-based system provides more accurate predictions for drug delivery to the eye.
Area of Science:
- Ophthalmology
- Pharmaceutics
- Biomedical Engineering
Background:
- Intravitreal drug delivery requires accurate in vitro models to predict in vivo performance.
- Current compendial methods may not adequately simulate the viscoelastic properties of the human vitreous body.
- Developing advanced dissolution models is crucial for optimizing ophthalmic drug formulations.
Purpose of the Study:
- To develop and validate the EyeFlowCell (EFC), a novel in vitro dissolution model for intravitreal dosage forms.
- To compare drug release profiles from model implants using the EFC versus compendial methods (USP Apparatus 4 and 7).
- To assess the EFC's ability to predict drug release in the human vitreous environment.
Main Methods:
- The EyeFlowCell (EFC) was designed as a 3D-printed flow-through cell incorporating a polyacrylamide (PAA) gel core with an agarose sheath.
- Drug release studies were conducted using hydroxypropyl methylcellulose implants containing triamcinolone acetonide or fluorescein sodium.
- Drug release was measured in the EFC, USP Apparatus 4, and USP Apparatus 7, with simulated eye movements (EyeMoS).
Main Results:
- The EFC demonstrated significantly slower drug release compared to USP Apparatus 4 and 7 for both model drugs.
- Fluorescein sodium release completed in 40 min (USP 4) versus 72 hours in the EFC.
- Triamcinolone acetonide release completed in 35 min (USP 4) and 150 min (USP 7) versus 96 hours in the EFC.
Conclusions:
- Standard compendial dissolution methods may overestimate intravitreal drug release rates.
- The gel-based EyeFlowCell (EFC) provides a more physiologically relevant simulation of the vitreous body.
- The EFC shows potential for more accurate prediction of drug release from intravitreal implants.
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