Treat and extend versus fixed regimen in neovascular age related macular degeneration: A systematic review and meta-analysis

Purpose: To compare efficacy of treat and extend (T&E) versus fixed regimen treatment protocols in neovascular age-related macular degeneration (nAMD). Methods: Randomized clinical trials (RCTs) comparing T&E versus fixed regimen protocols for nAMD were systematically searched. Primary outcome was to compare the mean best corrected visual acuity (BCVA) change in T&E regimen versus fixed regimen. Secondary outcomes were change in the mean optical coherence tomography (OCT) central retinal thickness (CRT) and mean number of injections. Standardized mean difference (SMD) along with 95% confidence intervals (CIs) were calculated. Random-effect models were used for meta-analyses. Results: Four RCTs were included, with a total of 649 and 621 eyes in the T&E and fixed regimen cohort at 12 months, and 267 and 249 eyes at 24 months. Pooled analysis of mean BCVA change included all four RCTs at 12 months and two RCTs at 24 months, showing no difference between the two groups (12-month: SMD = 0.08, 95% CI: -0.20 to 0.35, p = 0.55; 24-month: SMD = 0.04, 95% CI: -0.13 to 0.21, p = 0.64). Pooled analysis of OCT CRT change at 12 months included three studies, showing no difference between the two groups (SMD = 0.03, 95% CI: -0.46 to 0.51, p = 0.91). Pooled analysis of mean injection number included all four RCTs at 12 months and two RCTs at 24 months, showing significant difference between the two groups (12-month: SMD = -1.11, 95% CI: -1.67 to -0.56, p < 0.001; 24-month: SMD = -1.34, 95% CI: -1.54 to -1.15, p < 0.001). Conclusion: A T&E regimen proved as effective as a fixed dosage regimen throughout a 24-month follow-up and with a lower number of injections.