Estimated <i>in vivo</i> % residual human mitochondrial polymerase- activity in resting cells.

In vivo concentration ranges were 3TC-TP = 12.2–40.5; FTC-TP = 1.5–19.4; TFV-DP = 0.16–1.17; CBV-TP = 0.44–0.88; d4T-TP = 0.034–0.56; and AZT-TP = 0.0056–0.056 , respectively [56], [71], [73]–[75], assuming an average cell volume of for resting T-cells [72]. *calculated as the ratio of average effect on polymerase- and wildtype reverse transcriptase of HIV-1: . †mitochondrial toxicity of AZT has been attributed to mechanisms other than inhibition (see Discussion section).