NanoViricides, Inc. announced that antiviral activity of NV-387 against RSV/A2 is strong enough to have resulted in full survival of lethally infected animals was achieved. In this study, extended dosing of NV-387 given orally was compared with a high dose of ribavirin given orally for the same duration. Two doses were given on first day of dosing followed by one daily dose for next 9 days (for a total of 11 doses).

NV-387 given by this dosing regimen led to complete survival of the mice beyond the 21 days study period, with no signs of pathology (disease) apparent on the last day of observation. In contrast, ribavirin led to death of all animals by 14 days. Thus the company believe NV-387 oral treatment is capable of curing RSV infection.

There is currently no approved treatment for RSV other than ribavirin. A safe and effective treatment remains an unmet medical need. Ribavirin is the only currently approved drug for RSV infection, that can be used only as a last resort because of its extensive toxicity that limits its effectiveness.

Two vaccines have recently been approved for protection of persons 60+ years old from RSV infection (Arexvy®, GSK, and Abrysvo®, Pfizer). Abrysvo was recently approved for use in pregnant women for protection of infants. Synagis (palivizumab), an antibody, as well as a new antibody, nirsevimab (Beyfortus®) have been approved by the US FDA for protection of newborn children at risk of RSV disease, but not for treatment of RSV infection and disease.