FIG 2.

Box plots of tenofovir plasma concentrations in patients having the ABCC4 4131 TT genotype versus those having the TG or GG genotype by whether the patients were using ritonavir-boosted protease inhibitors as a comedication. ABCC4 4131T → G genotypes are shown on the x axis. The medians and interquartile ranges of tenofovir plasma concentrations are shown on the y axis. Among patients who did not use a ritonavir-boosted protease inhibitor, the median tenofovir plasma concentration was 85.0 ng/ml in patients with the ABCC4 4131 TG/GG genotype, whereas it was 80.0 ng/ml in those with the TT genotype. Among patients using a ritonavir-boosted protease inhibitor, the median tenofovir plasma concentration in patients with the ABCC4 4131 TG/GG genotype was 118.0 ng/ml, whereas it was 103.5 ng/ml in those with the TT genotype. After controlling for body weight, eGFR, and concomitant use of a ritonavir-boosted protease inhibitor, patients having the ABCC4 4131 TG/GG genotype had, on average, a 30% higher mean tenofovir plasma concentration than those having the TT genotype (P = 0.007).