Metabolite-to-endogenous nucleotide ratio boxplots across eight tissues for FTCtp (A) and TFVdp (B). Dotted lines represent literature-derived 90% effective concentrations. NHP, nonhuman primate; BLQ, below limit of quantification; N/A, not applicable; FGT, female genital tract; FTCtp, emtricitabine triphosphate; TFVdp, tenofovir diphosphate. Testes were only evaluated in NHPs. *, P < 0.05 via Wilcoxon rank-sum test with Benjamini Hochberg P value adjustment procedure.