The study is designed to identify the maximum tolerated dose (MTD) for intravitreal (IVT) administration of GEM103 in subjects with geographic atrophy (GA) secondary to dry AMD. Safety and tolerability of a single dose of GEM103 will be assessed based on the occurrence of dose-limiting toxicities (DLTs). Each subject will be followed for safety, pharmacokinetic (PK), clinical, and biomarker evaluations. Three escalating dose cohorts are planned.

This is a Phase 1, multicenter, open-label, single-dose, dose-escalation study in subjects with GA secondary to dry AMD to investigate the safety, tolerability, pharmacodynamics (PD), and immunogenicity of IVT injections of GEM103 to a single eye.

The study is designed to identify the MTD for IVT administration of GEM103. Safety and tolerability of a single dose of GEM103 will be assessed based on the occurrence of DLTs. Three escalating dose cohorts are planned.

Subjects will undergo clinical and ophthalmic assessments for inclusion eligibility into the study. Enrolled subjects will receive GEM103 and be followed for safety, PK, clinical, and biomarker evaluations.

Inclusion Criteria:

1. At least 50 years old at the time of signed informed consent
2. Able to cooperate sufficiently for adequate ophthalmic visual function testing and anatomic assessment and provide informed consent prior to initiation of any study procedure
3. Best corrected visual acuity (BCVA) in study eye between 5-45 letters
4. Confirmed diagnosis of central GA in the study eye and eligible total GA lesion size

Exclusion Criteria:

1. Presence of the following ocular conditions - in the study eye:

   • Exudative AMD or choroidal neovascularization (CNV)
   • Any ocular disease or condition that could impact the subject's ability to participate in the study or be a contraindication to IVT injection
   • Any intraocular surgery (with the exception of intraocular lens replacement surgery more than 3 months prior to consent)

2. Presence of any of the following ocular conditions - in either eye:

   • History of herpetic infection
   • Ongoing treatment with antiangiogenic therapies in the fellow eye or completed treatment in the study eye

3. Any prior or ongoing medical condition (e.g. ocular other than dry AMD, systemic, psychiatric) or clinically significant screening laboratory value that may present a safety risk, interfere with study compliance, interfere with consistent study follow-up, or confound data interpretation throughout the longitudinal follow-up period

4. Female subjects must not be pregnant or lactating

5. Current use of medications known to be toxic to the lens, retina, or optic nerve