October 2021

Extended intervals for wet AMD patients with high retreatment needs: informing the risk during COVID-19, data from real-world evidence

Kelvin Yi Chong Teo, Vuong Nguyen, Daniel Barthelmes, Jennifer J Arnold, Mark C Gillies, Chui Ming Gemmy Cheung


Background/objective: Some clinicians may be forced to temporarily extend treatment intervals in neovascular age-related macular degeneration (nAMD) eyes with frequent retreatments to reduce the number of visits during the COVID-19 pandemic. To provide an indication of what these outcomes may be, we studied eyes with active lesions with unplanned treatment interval extensions before the pandemic occurred.

Methods: We compared eyes with active disease despite ≤6 weekly injections whose next injection was extended to ≥7 weeks and those whose intervals were not extended. We identified 1559 (16%) of 9602 eyes from the Fight Retinal Blindness! (FRB!) registry (2013 and 2018) that fit this criteria. Eyes were further stratified into four groups by the mean interval over the following 6 months: (1) ≤6 weeks (81%), (2) 7-9 weeks (9%), (3) 10-12 weeks (5%) and (4) >12 weeks (5%).

Results: There was a significant loss in VA in eyes extended to >12 weeks compared to the non-extended group (adjusted VA change, mean (95% CI): ≤6 weeks, 0.4 (-1.5 to 2.2), versus >12 weeks, -4.7 (-7.4 to -2.1), letters, p = 0.03 and a threefold increase in relative risk of losing ≥15 letters (absolute risk (14% versus 4%, p < 0.01)). Conclusion: Mean VA remained stable for 6 months in eyes requiring frequent treatment despite retreatment interval extension up to 10-12 weeks. There was a significant short-term risk to vision when retreatment interval was extended beyond 12 weeks, hence extensions to this level should be considered cautiously. These data may be useful for physicians who are considering reducing visits to mitigate the risk of COVID-19.