Computational modeling of intravitreal ranibizumab kinetics: Predicting macular drug concentration and half-life
Jabia Mostofa Chowdhury
Abstract
Ranibizumab is a key anti-VEGF therapeutic used to improve treatment efficacy and reduce injection frequency in neovascular retinal diseases. Because experimental pharmacokinetic data in humans are limited, computational modeling provides an effective means to predict ocular drug behavior. In this study, a three-dimensional computational model of the human eye was developed in COMSOL Multiphysics 6.3 to analyze the pharmacokinetics of ranibizumab following intravitreal injection.
Introduction
Neovascular eye diseases, including age-related macular degeneration (AMD), diabetic retinopathy (DR), and retinal vein occlusion (RVO), are characterized by abnormal blood vessel growth driven by overexpression of vascular endothelial growth factor (VEGF) [1,2]. These conditions represent a significant and growing public health concern, affecting millions of individuals worldwide.
Methods
Vitreous humor
Vitreous humor is a colorless, viscoelastic gel-like substance that is the largest part of the eye. Interestingly, no blood vessels are present in this part; rather, its gelatinous consistency is attributed to the presence of hyaluronic acid and collagen [21–23].
Results
Our pharmacokinetic study compares the ranibizumab concentration profiles in the vitreous for all four modeled scenarios, summarized in Fig 2. We attempted to investigate the impact of vitreous modeling on the drug transport mechanism in human vitreous. The results provide a controlled assessment of the extent to which partial liquefaction alone alters intravitreal pharmacokinetics.
Discussion
The present study developed a three-dimensional computational framework to investigate the intravitreal pharmacokinetics of ranibizumab and to estimate drug concentration dynamics at the macular region, the primary therapeutic target in neovascular retinal diseases. The model captures key transport mechanisms, including diffusion and convection within the vitreous humor, and evaluates the influence of vitreous structure and elimination pathways.
Acknowledgments
The author thanks Dr. Ashlee N. Ford Versypt for her valuable guidance during this work. The author also acknowledges Texas A&M University–Texarkana for its academic support.
Citation: Chowdhury JM (2026) Computational modeling of intravitreal ranibizumab kinetics: Predicting macular drug concentration and half-life. PLoS One 21(5): e0348811. https://doi.org/10.1371/journal.pone.0348811
Editor: Yalong Dang, Sanmenxia Central Hospital, Henan University of Science and Technilogy, CHINA
Received: November 23, 2025; Accepted: April 21, 2026; Published: May 7, 2026
Copyright: © 2026 Jabia Mostofa Chowdhury. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: All relevant data are within the manuscript.
Funding: The author(s) received no specific funding for this work.
Competing interests: The authors have declared that no competing interests exist.
