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Enrolment characteristics in age-related macular degeneration clinical trials: a cross-sectional study

Eye volume 39, pages 1153–1159 (2025)Cite this article

Subjects

Abstract

Background/Objectives

To investigate demographic enrolment characteristics in age-related macular degeneration (AMD) trials.

Subjects/Methods

Clinicaltrials.gov was searched with “age-related macular degeneration” to identify RCTs with double, triple, or quadruple masking. Trial (e.g., study location, phase, masking, trial initiation year, and sponsor origin) and patient demographic data were collected. Sex-based AMD disease burdens were retrieved from the Global Burden of Disease database to calculate pooled female population-to-prevalence ratios (PPRs). Equitable trial enrolment was defined as PPR between 0.8–1.2. Demographic proportions were evaluated across trial characteristics using the Kruskal–Wallis test (alpha = 0.05) followed by post hoc comparisons. Secondary outcomes included absolute number of enrolled female, racial, and ethnic groups, and the association of trial characteristics with these demographics.

Results

We included 106 trials (77,939 patients; 46.3% female), spanning 1990–2020. The pooled female PRR was 0.88 (95% confidence interval [CI]: 0.82, 0.94). PPR values were inconclusive studies with quadruple blinding; phase I, III, IV, or not applicable status; foreign (non-US) site; US-only and foreign-only sponsor; and an initiation year before 2010. There was no significant difference in PPR between sublevels of analysed trial characteristics. Of the 74 (69.8%) trials that adequately detailed race, White participants comprised the largest group (N = 57,917; 82% of total participants). Thirty-seven (34.9%) trials adequately detailed ethnicity. The absolute enrolment of race and ethnic groups did not generally exhibit significant difference between sublevels of analysed trial characteristics.

Conclusions

Female enrolment was commensurate to their disease burden across all trial characteristics. Race and ethnicity were under-reported. Future trials should prioritise equitable study enrolment strategies.

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Data availability

Available upon reasonable request to the corresponding author.

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Author information

Authors and Affiliations

  1. Faculty of Medicine, The University of British Columbia, 317-2194 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada

    Brendan K. Tao

  2. Department of Ophthalmology and Vision Science, University of Toronto, Suite 400, 340 College Street, Toronto, ON, M5T 3A9, Canada

    Jim S. Xie, Peng Yan, Rajeev Muni & Radha P. Kohly

  3. Temerty Faculty of Medicine, University of Toronto, 6 Queen’s Park Crescent West, Toronto, ON, M5S 1A8, Canada

    Victoria Leung

  4. Faculty of Medicine, University of Ottawa, 451 Smyth Road #2044, Ottawa, ON, K1H 8M5, Canada

    Milin Patel

  5. Faculty of Science, McMaster University, 1280 Main Street West, Hamilton, ON, L8S 4L8, Canada

    Jeffrey Xu

  6. Ottawa Hospital Eye Institute, University of Ottawa, 501 Smyth Road, Ottawa, ON, K1H 8M2, Canada

    Cody Lo

  7. Department of Ophthalmology and Visual Science, The University of British Columbia, 2550 Willow St., Vancouver, BC, V5Z 3N9, Canada

    Nawaaz Nathoo, Wai-Ching Lam & Eduardo V. Navajas

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  1. Brendan K. Tao
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Contributions

Conceptualisation: BT, JSX, RK; methodology: BT, JSX; software: BT; validation: all authors; formal analysis: BT; investigation: BT, JSX, VL, MP, JX; resources: BT; data curation: BT, JSX, VL, MP, JX; writing original draft: all authors; writing review & editing: all authors; visualisation: BT; supervision: JSX, CL, PY, NN, WCL, EVN, RM, RK; project administration: BT; funding acquisition: not applicable.

Corresponding author

Correspondence to Radha P. Kohly.

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The authors declare no competing interests.

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Under article 2.4 of the Tri-Council Policy Statement, institutional review board approval was waived since all data were sources from published primary research and publicly available registries. No identifiable information was generated by this work.

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Tao, B.K., Xie, J.S., Leung, V. et al. Enrolment characteristics in age-related macular degeneration clinical trials: a cross-sectional study. Eye 39, 1153–1159 (2025). https://doi.org/10.1038/s41433-024-03572-6

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