Zentek Ltd. announced that its wholly-owned subsidiary Triera Biosciences Ltd. (Triera) has completed testing demonstrating that its C19HBA SARS-CoV-2 universal aptamer built on the proprietary high-binding affinity aptamer platform has shown a promising safety and toxicity profile in preclinical testing. This is a critical step in the path towards the development of a human therapeutic. Previously, the Company reported successful efficacy when C19HBA was tested as a prophylaxis and as a therapeutic.

In repeated trials against SARS-CoV-2 variants, C19HBA has matched or exceeded the clinical protection compared to a leading monoclonal antibody (LMA). In a trial completed in February 2024 by the Miller lab at McMaster University, the safety and toxicity of C19HBA was assessed through a study that administered 258 µM of C19HBA intranasally to one cohort of mice with a similar sized cohort receiving sham treatment. After two hours, half the mice from each cohort were sacrificed while the remaining mice were infected with a lethal challenge of the ancestral variant of SARS-CoV-2. After 24 hours all infected mice were sacrificed, and serum and BAL fluid samples were collected.

These samples were analyzed for inflammatory cell infiltration and full cytokine panel. The inflammatory cell infiltration study demonstrated that mice treated with C19HBA had similar levels of macrophages, neutrophils, and monocytes as the naïve mice both at the two-hour mark after C19HBA administration and 24 hours after infection. The cytokine panel analyzed 44 different biomarkers from the Bronchoalveolar Lavage ("BAL") BAL fluid of sacrificed mice.

The major cytokine markers, VEGF-A and TNFa were consistent between naïve mice and those treated with C19HBA.