Sex-dependent differences in liver drug concentrations in mice treated with nanoATV/r. Mice were treated intramuscularly with 20 or 50 mg/kg nanoATV/r or 50 mg/kg nanoATV on days 0, 3, 7, 14, and 21 and livers were collected on day 28. Liver ATV (A) and RTV (B) concentrations were determined by UPLC tandem MS. Males, solid bars; females, hatched bars. Data are expressed as mean ± S.E.M. *Significantly different than respectively treated male mice (P < 0.05). N = 4 to 5 (nanoATV/r-treated males); N = 3 (nanoATV/r-treated females; nanoATV-treated males); N = 2 (nanoATV-treated females).