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bioRxiv · 10.1101/2025.10.03.680220

Investigation of anti-SARS CoV-2 multimeric bicyclic peptide inhibitors in a range of pre-clinical therapeutic settings

Abstract

The spread of respiratory viruses, such as Influenza and SARS-CoV-2 has presented significant challenges over the last 30 years with few effective therapeutic options available to this day. Bi-cyclic peptides represent a unique, modular, modality in the antiviral armamentarium against future pandemics. This study provides a deeper evaluation of multivalent bi-cyclic (Bicycle(R)) molecule efficacy in several preclinical SARS-CoV-2 challenge settings. We explore both pre-exposure prophylaxis and post-exposure therapeutic settings via subcutaneous and intranasal routes of administration. We contextualize this further in bespoke scenarios of immune compromisation, and viral transmission. Promisingly, in all studies we observe efficacy, significantly reducing infectious viral burden at each study endpoint. These data further support candidacy of Bicycle molecules as a differentiated antiviral therapeutic class in the context of pandemic preparedness. ImportanceThe COVID-19 pandemic, triggered a rapid wave of innovation, accelerating the delivery of new vaccine technology and anti-viral treatments. In our first paper, we described the discovery and molecular optimization of Bicycle molecules as a novel drug class for the potential treatment of SARS CoV-2. Here, we have performed deeper characterization of these molecules in established animal models that simulate SARS-CoV-2 transmission, testing more convenient delivery routes, such as intra-nasal. The Bicycle molecules demonstrated positive outcomes in each of these studies and suggest that Bicycle molecules, as convenient and effective anti-viral treatments, could be an important addition to help future preparedness against new viral pandemics.

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BibTeXRIS

Harman, M. A. J., Gaynor, K. U., Papa, G., Pellegrino, S., Bezerra, G. A., McGuinness, B., Jeffrey, P., Beswick, P., Stanway, S., van Rietschoten, K., Chen, L., Drulyte, I., Herriott, J., Kijak, E., Gallardo Toledo, E., Tatham, L., Sharma, P., Bentley, E., Sharp, J., Kirby, A., Owen, A., Stewart, J. P., Skynner, M. J.. 2025-10-05. Investigation of anti-SARS CoV-2 multimeric bicyclic peptide inhibitors in a range of pre-clinical therapeutic settings. https://doi.org/10.1101/2025.10.03.680220

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