Abstract
INTRODUCTION: Clinical trials in neovascular age-related macular degeneration (nAMD) using anti-vascular endothelial growth factor (ant-VEGF) injections use disease activity (DA) criteria to shorten, maintain or increase the interval between injections. Differences in these DA criteria may contribute to differences in the proportions of patients with macular fluid at key time points or achieving extended dosing intervals in these trials. We identified, collated and evaluated DA criteria from pivotal anti-VEGF nAMD trials to understand how differences impact on these studies and real-world visual acuity and extending dosing outcomes. METHODS: This was a systematic review of literature on Pubmed for randomised clinical trials in nAMD using a proactive treatment regimen. We excluded case reports, review articles and studies on fewer than 50 participants. RESULTS: Twelve clinical trials (LUCAS, VIEW, TREX-AMD, FLUID, TREND, RIVAL, ALTAIR, CANTREAT, ARIES, TREX-Conbercept, HAWK & HARRIER, TENAYA & LUCERNE) investigating anti-VEGF treatment of nAMD were identified according to our search strategy. Different studies utilised a different combination of DA criteria. Specifically, six trials included visual acuity change; four included macular thickness change; one included visual acuity change if associated with macular thickness change; one with qualitative optical coherence tomography (OCT) features; four with qualitative OCT features if also associated with visual acuity change; 10 with macular haemorrhage and five with other fluorescein angiographic features. CONCLUSION: Different clinical trials use different DA criteria when altering the interval between anti-VEGF injections. This makes it difficult to draw meaningful conclusions about secondary outcomes such as proportion of patients treated at extended dosing intervals or proportions of eyes with persistent subretinal or intraretinal fluid. Standardising DA criteria in clinical trials and preferentially using those easily applied in a real-world setting would lead to results more achievable in real-world settings and for a meaningful comparison of treatment durability.