Safety and tolerability of RPESC-RPE transplantation in patients with dry age-related macular degeneration: Low-dose clinical outcomes.

Retinal pigment epithelium (RPE) cell atrophy in dry age-related macular degeneration (AMD) compromises photoreceptor cell function, leading to vision loss. Stem cell-based RPE replacement therapy aims to reverse disease progression and restore vision. RPESC-RPE-4W, a post-mitotic adult RPE stem cell-derived RPE (RPESC-RPE) progenitor cell product, exhibits consistent safety and efficacy in preclinical studies. The first-in-human clinical trial of RPESC-RPE-4W completed low-dose cohort 1 interventions (NCT04627428). Six subjects received a subretinal suspension of 50,000 RPESC-RPE-4W cells. No significant inflammation, tumor, or product-related serious adverse events were observed. Best-corrected visual acuity in the three worse-seeing group A subjects improved by an average of +21.67 letters from baseline at 12 months. Three better-seeing group B subjects improved by an average of +3.0 letters at 6 months. The positive safety and tolerability outcomes for low-dose cohort 1 enabled dose escalation to mid-dose RPESC-RPE-4W therapy for dry AMD.