AT-527(Bemnifosbuvir hemisulfate), a hemisulfate salt of AT-511, a guanosine nucleotide prodrug, is a potent and orally active HCV viral replication inhibitor. AT-527 is highly effective in the control of SARS-CoV-2 (COVID-19) infection in vitro (EC90=0.47 μM). Bemnifosbuvir hemisulfate has pangenotypic antiviral activity[1][2][3].Bemnifosbuvir hemisulfate has pan-genotypic antiviral activities that inhibits HCV genotype 1a (HCV GT1a), HCV GT1b, HCV GT2a, HCV GT3a, HCV GT4a, and HCV GT5a replication with EC50 values of 12.8 nM, 12.5 nM, 9.2 nM, 10.3 nM, 14.7 nM, and 28.5 nM, respectively[1]. In normal human airway epithelial cells, the concentration of Bemnifosbuvir hemisulfate required to inhibit replication of SARS-CoV-2 by EC90 is 0.47 μM, very similar to its EC90 against HCoV-229E, HCoV-OC43 and SARS-CoV in Huh-7 cells[2].When given orally to rats (500 mg/kg) and monkeys (30 mg/kg, 100 mg/kg or 300 mg/kg), Bemnifosbuvir hemisulfate preferentially delivers high levels of AT-9010 in the liver in vivo[1].

FOY 251 is a metabolite of Camostat and a pollen protease inhibitor for prevention and control of allergy.

Sisunatovir (RV521), an orally available inhibitor of the RSV fusion (RSV-F) protein, exhibits potent efficacy against a panel of clinical isolates of RSV-A and RSV-B viruses, with IC50s of 1.4 nM and 1.0 nM, respectively.

Sisunatovir, also known as RV521, is a highly potent fusion inhibitor with efficacy against a panel of clinical isolates of RSV-A and RSV-B viruses. RV521 exhibited a mean IC50 of 1.2 nM against a panel of RSV A and B laboratory strains and clinical isolates with antiviral efficacy in the Balb/C mouse model of RSV infection. Oral bioavailability in preclinical species ranged from 42 to >100% with evidence of highly efficient penetration into lung tissue. In healthy adult human volunteers experimentally infected with RSV, a potent antiviral effect was observed with a significant reduction in viral load and symptoms compared to placebo.

Colchicine is a potent therapeutic tool against COVID-19. Colchicine is a tricyclic alkaloid that is extracted from the plant Colchicum autumnale. Colchicine acts as a potent inhibitor of tubulin polymerization.

GRL-1720 is an irreversible, covalent inhibitor of SARS-CoV-2 main protease (Mpro) with EC50 of 15 µM.

PF00835231(SARS-CoV-2 inhibitor 5h) is areversible-covalent inhibitor of SARS-CoV-2 main protease (Mpro) with EC50 of 4.2 µM. Compound 5h blocks the infectivity and cytopathicity of the virus with high potency and without any detectable cytotoxicity even at 200 µM.PF-00835231 is a potent inhibitor of CoV-2 3CLpro with IC50 of 4 nM and shows suitable pharmaceutical properties to warrant further development as an intravenous treatment for COVID-19.