A Multiple Dose Study of AVD-104 for Geographic Atrophy (GA) Secondary to Age-Related Macular Degeneration (AMD) (SIGLEC)

Inclusion Criteria: Part 1: BCVA in the study eye using ETDRS Chart Visual Acuity Scale (VAS) of 5 to 55 letters (equivalent to Snellen VA of approximately 20/800 - 20/80) If GA is multifocal, at least one focal lesion must be ≥ 1.25 mm2 (0.5 DA) GA may be center involved. Part 2: BCVA in the study eye using ETDRS Chart VAS of 24 letters or better (equivalent to Snellen VA of 20/320 or better) Confirmed diagnosis of AMD that is non-center involving (i.e., non-sub-foveal) GA in 75% of participants. Center involvement allowed in 25% of participants. The entire GA lesion must be completely visualized on the macula centered image and must be able to be imaged in its entirety and not contiguous with any areas of peripapillary atrophy. Exclusion Criteria: Participants are excluded from the study if any of the following criteria apply: Part 1 and 2 - Presence of the following ocular conditions - in the Study Eye: Exudative AMD or choroidal neovascularization (CNV), including any evidence of retinal pigment epithelium rips or evidence of neovascularization anywhere based on spectral domain optical coherence tomography (SD-OCT) imaging and/or fluorescein angiography as assessed by the Reading Center. Any ocular condition other than GA secondary to AMD that may require surgery or medical intervention during the study period or, in the opinion of the Investigator, could compromise visual function during the study period.