Apricitabine (SPD754) is a highly selective and orally active HIV-1 reverse transcriptase inhibitor (Ki=0.08 μM), the (-) enantiomer of 2′-deoxy-3′-oxy-4′-thiocytidine (dOTC) . Apricitabine inhibits DNA polymerase α, β and γ with Ki values of 300 μM, 12 μM and 112.25 μM, respectively. Apricitabine has shown good antiretroviral therapeutic efficacy in antiretroviral HIV-infected patients, with good tolerability and low selective resistance.

Apricitabine (SPD754 ; AVX754) is against clinical isolates of HIV-1 in cultured PBMCs with IC50 values of 0.2 μM, 1.45 μM, 2.2 μM and 2.4 μM for HIV-1RF, Wild type, 3TC resistant, 3TC and AZT resistant, respectively[1].
Apricitabine (SPD754 ; AVX754) has antiviral activities against HIV-1 clinical isolates resistant to nucleoside reverse transcriptase inhibitors in MT-4 cells, exhibits Mean IC50 values of 20 μM, 25 μM, 30 μM,21 μM,55 μM,32 μM and 71 μM. It is for HIV-1IIIB, Wild-type(control), Zidovudine-resistant/lamivudine-resistant, Zidovudine-resistant, Lamivudine-resistant, Abacavir-resistant and Stavudine-resistant viruses, respectively.[2]

Apricitabine (SPD754 ; AVX754) (intravenous injection ; 10 mg/kg ; once a day) exhibits the T1/2, AUC0–∞ values of 12.7 mins, 226.9 μg/min/ml in female rats[1]. Apricitabine (SPD754 ; AVX754) (oral adminstation ; 10 mg/kg ; once a day) exhibits a good oral bioavailability of 68% for males and 69.4% for females rats and the T1/2, AUC0–∞, Tmax, Cmax are 62.2 mins, 157.4 μg/min/ml and 37.3 mins, 1.16 μg/ml in female rats.[1]