HIV-1, NRTIs

Tenofovir alafenamide fumarate (GS-7340 fumarate) antiviral activities are similar across all cell types, ranging from 5 to 7 nM, while the CC ₅₀ varies from 4.7 to 42 μM for MT-4 and MT-2 cells, respectively. The antiviral activity of TAF is evaluated against a panel of HIV-1 and HIV-2 isolates, including HIV-1 group M subtypes A to G, as well as group N and O isolates. Overall, for the 29 primary HIV-1 isolates tested in PBMCs, TAF EC ₅₀ s range from 0.1 to 12 nM, with a mean EC ₅₀ of 3.5 nM compared to a mean EC ₅₀ of 11.8 nM for AZT, which is used as an internal control. For the HIV-2 isolates, the mean EC ₅₀ s are 1.8 nM for TAF and 6.4 nM for AZT.

Tenofovir alafenamide fumarate (GS-7340 fumarate) is an amidate prodrug of Tenofovir with good oral bioavailability and increases plasma stability compared to Tenofovir disoproxil fumarate (TDF).