DIOS-203

DIOS-203 is a preclinical, nanobody-based antiviral candidate being developed by DiosCURE Therapeutics as a multivalent single-chain antibody construct targeting SARS-CoV-2 for the treatment and potential prevention of COVID-19.[3][7][11][13] It consists of engineered combinations of camelid-derived single-domain antibodies (VHHs/nanobodies) that bind distinct epitopes on the coronavirus spike glycoprotein, enabling high-avidity, synergistic neutralization and inactivation of virions, including variants with rapidly mutating spike proteins.[1][4][9][13] Designed using detailed structural information on VHH–spike interactions and functional and evolutionary experiments, DIOS-203 exemplifies next-generation passive immunotherapy that aims to provide potent, manufacturable, and potentially more tissue-penetrant antibody-based protection compared with conventional monoclonal antibodies.[1][3][4][11][13][15]