Discovery of Sisunatovir (RV521), an Inhibitor of Respiratory Syncytial Virus Fusion.
Cockerill, G.S., Angell, R.M., Bedernjak, A., Chuckowree, I., Fraser, I., Gascon-Simorte, J., Gilman, M.S.A., Good, J.A.D., Harland, R., Johnson, S.M., Ludes-Meyers, J.H., Littler, E., Lumley, J., Lunn, G., Mathews, N., McLellan, J.S., Paradowski, M., Peeples, M.E., Scott, C., Tait, D., Taylor, G., Thom, M., Thomas, E., Villalonga Barber, C., Ward, S.E., Watterson, D., Williams, G., Young, P., Powell, K.(2021) J Med Chem 64: 3658-3676
- PubMed: 33729773 
- DOI: https://doi.org/10.1021/acs.jmedchem.0c01882
- Primary Citation of Related Structures:  
7KQD - PubMed Abstract: 
RV521 is an orally bioavailable inhibitor of respiratory syncytial virus (RSV) fusion that was identified after a lead optimization process based upon hits that originated from a physical property directed hit profiling exercise at Reviral. This exercise encompassed collaborations with a number of contract organizations with collaborative medicinal chemistry and virology during the optimization phase in addition to those utilized as the compound proceeded through preclinical and clinical evaluation. RV521 exhibited a mean IC 50 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.
Organizational Affiliation: 
Reviral Ltd., Stevenage Bioscience Catalyst, Gunnels Wood Road, Stevenage, Hertfordshire SG1 2FX, U.K.