Oseltamivir phosphate (GS 4104) is the phosphate salt of oseltamivir, a synthetic derivative prodrug of ethyl ester with antiviral activity. By blocking neuraminidases on the surfaces of influenza viruses, oseltamivir interferes with host cell release of complete viral particles.

Oseltamivir Phosphate, anti-Neu1 antibodies, and matrix metalloproteinase-9-specific inhibitor blocks Neu1 activity associated with EGF-stimulated TNBC MDA-MB-231 cells[2]. Oseltamivir slows the spread of influenza (flu) virus between cells in the body by stopping the virus from chemically cutting ties with its host cell.

Oseltamivir Phosphate monotherapy may be the effective treatment therapy for TNBC(Triple-negative breast cancers)[2]. It is efficacious in treating infections caused by H5N1 and H9N2 influenza viruses in mice[3]. After dosing, the prodrug (Oseltamivir phosphate) is readily absorbed from the gastrointestinal tract and rapidly converted into the active metabolite, OC. In all patient groups, OC has high bioavailability and is systemically distributed to infection sites at concentrations sufficient to inhibit a range of influenza virus neuraminidases[4].

Cells are incubated in 96-well plates (5,000 cells/well) and allowed to adhere for 24 hours in 1× DMEM media containing 10% FCS. The media are replaced with fresh DMEM media containing 5% FCS with or without various concentrations of tamoxifen or OP for indicated time periods. Cell viability is tested using WST-1 cell proliferation assay.(Only for Reference)