Author’s Disclosure Block: Mélanie Hébert: Bayer, Grant/research support, Vision Health Research Network, Grant/research support, Fighting Blindness Canada, Grant/research support; Valérie Gagné: none; Jean-Philippe Rozon: none; Serge Bourgault: none; Mathieu Caissie: none; Laurence Letartre: none; Éric Tourville: none; Ali Dirani: none

Abstract Body
Purpose: To evaluate the real-world performance of the recently approved bispecific antibody faricimab in patients switched from other anti-vascular endothelial growth factor (VEGF) treatments for neovascular age-related macular degeneration (nAMD). Study Design: Single-center retrospective cohort study Methods: The study included all consecutive patients switched to faricimab injections for nAMD (n=226 eyes) between 2022 and 2024 at the Centre Oculaire de Québec. Effect on best-corrected visual acuity (BCVA), central macular thickness (CMT), and treatment intervals were assessed before the switch, during faricimab injections, and after a switchback in applicable patients. Results: Among 226 eyes treated, median BCVA prior to the anti-VEGF switch to faricimab was 0.32 [0.18, 0.56] and median CMT was 250 [225, 294] μm. Prior to the switch, eyes had received a median of 16 [7, 45] injections and the last interval was 38 [28, 49] days. After switching to faricimab, between the 1st and 3rd injections, BCVA improved significantly by one line of vision in a quarter of patients and remained stable vision in half (median 0.00 [-0.10, 0.04], p=0.02), while CMT decreased significantly by -7 [-27, 2] μm (p<0.001). At the last follow-up visit, the median number of injections was 7 [5, 10] injections and the treatment interval had increased to 49 [36, 63] days (p<0.001, as compared to last interval before switch).There were 1.3% (n=3) switchbacks to aflibercept after 4 to 9 faricimab injections. These patients were significantly younger at a median age of 67 years compared to 80 years (p=0.01). Reasons for switchback were varied with three having lost between one and two lines in vision by the 3rd injection which was later recuperated in two of them, and one experiencing a decrease in treatment interval under faricimab. After switching back to aflibercept, one patient had continued decreasing vision losing an additional three lines, one had stable vision despite CMT decreasing by 41 μm, while another only received a single injection to date. Conclusion: These real-world findings suggest that switching to faricimab injections significantly improve BCVA, decrease CMT, and decrease treatment intervals in patients with nAMD, especially during the loading phase. However, some patients may be non-responders and could benefit from a switchback to another anti-VEGF treatment