A Retrospective Study of Ranibizumab Treatment Regimens for Neovascular Age-Related Macular Degeneration (nAMD) in Australia and the United Kingdom

Introduction: Neovascular age-related macular degeneration (nAMD) is the leading cause of vision loss among persons aged 65 years and older. Anti-vascular endothelial growth factor (anti-VEGF) treatment is the recommended standard of care. The current study compares the effectiveness of ranibizumab in routine clinical practice in two countries that generally apply two different treatment regimens, treat-and-extend (T& E) in Australia or pro re nata (PRN) in the UK. Methods: This retrospective, comparative, non-randomised cohort study is based on patients' data from electronic medical record (EMR) databases in Australia and the UK. Treatment regimens were defined based on location, with Australia as a proxy for analysing T& E and UK as a proxy for analysing PRN. The study included patients with a diagnosis of nAMD who started treatment with ranibizumab between January 2009 and July 2014. A total of 647 eyes of 570 patients in Australia and 3187 eyes of 2755 patients in the UK with complete 12-months follow-up were analysed. Results: Baseline patient characteristics were comparable between the two cohorts. After 1 year of treatment, T& E-treated eyes achieved higher mean (+/- SE) visual acuity (VA) gains (5.00 +/- 0.54 letters [ 95% confidence interval (CI) 3.93-6.06]) than PRN-treated eyes [ 3.04 +/- 0.24 letters (95% CI 2.57-3.51); difference in means 2.07 +/- 0.69 (95% CI 0.73-3.41), p<0.001]. Non-inferiority of T& E compared to PRN was concluded based on the change in mean visual acuity gains at 12 months. Over the 12-month follow-up, T& E-treated eyes received a higher mean [+/- standard deviation (SD)] number of injections (9.29 +/- 2.43) than PRN-treated eyes (6.04 +/- 2.19) (p<0.0001).Australian patients had a lower mean (+/- SD) number of total clinic visits ( 10.29 +/- 2.90) than UK patients ( 11.47 +/- 2.93) ( p<0.0001). Conclusion: The higher injection frequency in the T& E cohort may account for the trend toward improved vision.