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Patel, Praveen J., MA, MBBChir, FRCOphth; Tufail, Adnan, MD, FRCOphth for the ABC Trial Investigators

doi: 10.1097/IAE.0b013e31823f0ba3
Original Study: PDF Only

Purpose The purpose of this study was to evaluate a standardized retreatment strategy with intravitreal bevacizumab in the treatment of neovascular age-related macular degeneration.

Methods In this double-masked randomized trial, patients with neovascular age-related macular degeneration were randomized to intravitreous bevacizumab or standard care. Bevacizumab treatment was given at 6 weekly intervals with 3 consecutive injections (loading phase) followed by variable dosing to Week 54 using standardized retreatment criteria.

Results Three hundred and eighty retreatment decisions were made after 3 fixed injections for 64 patients randomized to bevacizumab that completed 1-year follow-up. The most common criterion for retreatment was persistent intraretinal fluid on optical coherence tomography imaging, and fluorescein angiography did not drive any retreatment decision. The mean (median) change in visual acuity and optical coherence tomography central macular thickness after the 3 loading treatments to Week 54 was +0.4 (+1.0) letters and +2.0 (+1.0) μm, respectively, with a mean (median) of 7.1 (7.0) injections. The median time to retreatment was 42 days with 12 of 69 injection-free episodes (17%) lasting more than 3 months.

Conclusion Sustained improvements in structure and function were achieved using this 6 weekly variable-dosing regimen with intravitreal bevacizumab. Most retreatment decisions were based on qualitative interpretation of optical coherence tomography scans.

We report details of the retreatment strategy used in the ABC trial, a double-masked, randomized, controlled trial of Avastin (bevacizumab) for choroidal neovascularization in age-related macular degeneration, providing Level I evidence for variable-dosing retreatment using bevacizumab with 6 weekly visits.

NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, United Kingdom.

Reprint requests: Praveen J. Patel, MA, MBBChir, FRCOphth, NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital, 162 City Road, London EC1V 2PD, United Kingdom; e-mail:

Supported by the Special Trustees of Moorfields Eye Hospital. The authors acknowledge (a proportion of their) financial support from the Department of Health through the award made by the National Institute for Health Research to Moorfields Eye Hospital's NHS Foundation Trust and UCL Institute of Ophthalmology for a Specialist Biomedical Research Centre for Ophthalmology.

The views expressed in this publication are those of the authors and not necessarily those of the Department of Health. Trial registration, current controlled trials number ISRCTN83325075.

Dr P. J. Patel has received travel reimbursement for educational meetings from Novartis and Allergan. Dr A. Tufail has participated in advisory boards for Novartis, Allergan, GSK, and Pfizer and has received lecturing fees from Allergan and GSK. P.J. Patel and A. Tufail involved in conception and design of study (A.T.); analysis and interpretation (P.J.P., A.T.); writing the article (P.J.P.); critical revisions (P.J.P. and A.T.); final approval (P.J.P., A.T.); data collection (P.J.P.); provision of patients and resources (ABC Trial Investigators listed in Appendix A); statistical expertise (P.J.P.); obtaining funding (A.T.); literature search (P.J.P.); and research technical and administrative support (Clinical trials Unit staff and Research Governance Department, Moorfields Eye Hospital). Both Praveen J. Patel and Adnan Tufail, contributed equally to the success of this clinical study.

ABC Trial Investigators are listed in Appendix A.

© 2019 by Ophthalmic Communications Society, Inc.