In clinical trials, Zimura slowed the progression of GA over12 months in individuals with age-related macular degeneration.214 QR-504a from ProQR Therapeutics is an investigationalRNA ASO therapeutic that is in ongoing phase I/II clinical trials.216 QR-504a is designed to slow vision loss inindividuals with Fuchs endothelial corneal dystrophy (FECD) whichresults from trinucleotide repeat expansion mutations in the Transcriptionfactor 4 (TCF4) gene.217. This evidence concerns the gene TCF4 and Fuchs endothelial corneal dystrophy.