In the EVEROTAC 6-month prospective, open-label pharmacokinetic study, 35 renal transplant patients were randomized to receive EVR 0.75-mg bid or 1.5-mg bid in combination with standard-dose TAC (0.075-mg/kg bid adjusted

to achieve target C0 of 10–15 ng/mL from days 1–14 posttransplant, and then 5–10 ng/mL thereafter to month 6). EVR C0 levels were maintained between 3 and 8 ng/mL from day 42. From day 4 onward, exposure to TAC was similar with both doses of EVR (AUC: 162 ± 61 vs 171 ± 75 ng·h/mL). Significant differences in AUC were not seen, despite the EVR dose, because TAC dosing was adjusted to achieve target levels. Although the pharmacokinetic data suggest that neither EVR dose resulted in statistically significant differences in TAC exposure, the doses of TAC required to maintain target concentrations were buy Lumacaftor higher when administered with EVR 1.5 mg bid than with EVR 0.75-mg bid (12.5 mg vs 9.5 mg at day 14, and 9 mg vs 6 mg at day 42; p < 0.05 for both comparisons). Further, EVR appeared to decrease TAC exposure in a concentration-dependent manner. The data suggest that concomitant treatment with EVR 1.5-mg bid was effective in minimizing BYL719 exposure to TAC. However, further minimization of TAC exposure would likely require doses

of EVR greater than 3 mg/day because this dose was not enough to achieve EVR levels > 3 ng/mL during the first 2 weeks. From the limited

data discussed above, the findings suggest that co-administration with TAC does not influence exposure to EVR. The reported effects of EVR on TAC exposure, however, are, inconsistent. Bay 11-7085 There are only limited published data evaluating the interaction between SRL and TAC. In a recent pharmacokinetic study, both time- and concentration-dependent increases in TAC and SRL were reported. The study assessed drug exposure in 25 de novo kidney transplant patients, who, within 24 h of the transplant surgery were randomized to receive either SRL (15-mg loading dose, 5 mg for 7 days, and 2 mg thereafter) or MMF (2 g/day) for 6 months [37]. Both groups received TAC (0.10–0.15 mg/kg/dose) and corticosteroids. TAC doses were adjusted to keep blood concentration between 10 and 20 ng/mL for the first 30 days, 8–15 ng/mL during months 2 and 3, and 5–10 ng/mL thereafter. From day 7 to month 6, dose-normalized AUC0–12 for TAC increased by 59% in patients receiving SRL and 65% in patients receiving MMF. Over the same period, the dose-normalized AUC0–24 for SRL increased by 65%. Direct concentration-dependent correlations occurred between TAC and SRL blood levels. Increasing TAC or SRL doses were associated with parallel increases in exposure of SRL (p = 0.016) and TAC (p = 0.012), respectively (Fig. 2A and B).