Stapled Peptides Based on Human Angiotensin-Converting Enzyme 2 (ACE2) Potently Inhibit SARS-CoV-2 Infection <i>In Vitro</i>
Francesca Curreli, Sofia M. Benedict Victor, Shahad Ahmed, Aleksandra Drelich, Xiaohe Tong, Chien‐Te K. Tseng, Christopher D. Hillyer, Asim K. Debnath
Abstract
SARS-CoV-2 is a novel virus with many unknowns. No vaccine or specific therapy is available yet to prevent and treat this deadly virus. Therefore, there is an urgent need to develop novel therapeutics. Structural studies revealed critical interactions between the binding site helix of the ACE2 receptor and SARS-CoV-2 receptor-binding domain (RBD). Therefore, targeting the entry pathway of SARS-CoV-2 is ideal for both prevention and treatment as it blocks the first step of the viral life cycle. We report the design of four double-stapled peptides, three of which showed potent antiviral activity in HT1080/ACE2 cells and human lung carcinoma cells, A549/ACE2. Most significantly, the active stapled peptides with antiviral activity against SARS-CoV-2 showed high α-helicity (60 to 94%). The most active stapled peptide, NYBSP-4, showed substantial resistance to degradation by proteolytic enzymes in human plasma. The lead stapled peptides are expected to pave the way for further optimization of a clinical candidate.