RCT223

RCT223 is an investigational transfer RNA (tRNA)-based genetic medicine being developed by ReCode Therapeutics for the treatment of cystic fibrosis caused by premature termination codon (nonsense) mutations in the CFTR gene. Using a read-through, premature termination codon–suppressing tRNA delivered with ReCode’s lipid nanoparticle platforms, RCT223 is designed to bypass disease-causing stop mutations during translation, enabling production of full-length, functional CFTR protein in airway epithelial cells. In preclinical studies using patient-derived human bronchial epithelial cells, RCT223 restored CFTR channel function for at least 72 hours after a single administration and maintained or increased CFTR function with repeated dosing, supporting its potential as a disease-modifying therapy for individuals who do not benefit from existing CFTR modulators.