Clinical relevance of the time course of visual improvement following real-world anti-vascular endothelial growth factor (Anti-VEGF) therapy for neovascular age-related macular degeneration (nAMD)

Abstract

Purpose : To determine the time to achieve peak visual improvement (TPVI) in patients treated with ranibizumab or aflibercept for nAMD, and to determine whether TPVI influences visual outcomes

Methods : This retrospective analysis evaluated clinical history data from Australian patients undergoing anti-VEGF therapy for nAMD (14 clinics; 11 retina specialists; January 2000 to November 2022), consisting of treatment dates, drug administered and visual acuity (VA). All physicians used a treat-and-extend regimen, with full discretion over the choice of agent and treatment intervals. Snellen VA was recorded at each visit and converted to logMAR letters. TPVI was defined as the time between treatment initiation and the time at which the maximum vision was achieved.

ANOVA was used to test the relationship between TPVI and the following factors: treating physician; baseline vision; mean interval length; use of loading doses; anti-VEGF agent; switching of drugs; loss of vision subsequent to achieving peak vision; and overall visual change from treatment initiation to final VA.

Results : The mean TPVI across the cohort was 411 +/- 26 days (median: 119), varying significantly between physicians from 190 to 512 days (ANOVA p-value = 0.001) (Figure 1). Correspondingly, the mean number of injections to achieve PVI varied from 6.37 to 13.16 (overall mean: 9.52, median 4.0). Better baseline VA was associated with a significantly shorter mean TPVI: 379 days (median 120) for eyes with baseline VA > 80 Letters compared to 428 days (median 126) with baseline VA < 50 letters (p-value = 0.04) (Figure 2).

Eyes that were switched took significantly longer (529 days) to reach PVI compared to eyes that were not switched (348 days; p < 0.001).

Although somewhat statistically significant, relationships between TPVI and subsequent vision loss (r=-0.006; p = 0.67), actual PVI (r=0.336; p < 0.001), and final VA (r=0.117; p < 0.001) were weak.

Conclusions : The time taken to achieve peak vision only varies significantly by the treating physician. However, this has no influence on the visual outcomes achieved, in terms of maximum vision gained, subsequent loss of vision or overall visual change from baseline.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.

 

Time/number of injections to peak vision by doctor

 

Relationship between baseline vision and time to peak vision improvement (95% CI)