Leupeptin

Leupeptin， a broad-spectrum covalent inhibitor of serine， cysteine， and threonine proteases， showed inhibitory activity against Mpro， with a 50% inhibitory concentration (IC50) value of 127.2 μM in vitro in our study here. Leupeptin can also inhibit SARS-CoV-2 in Vero cells， with 50% effective concentration (EC50) values of 42.34 μM.[1]