During the post-transplant follow-up phase, patients were followed up for 48 weeks for evidence of recurrent HCV infection. All participating sites planned to use a standard post-transplantation immunosuppressive regimen of solumedrol/prednisone, tacrolimus,

and/or mycophenolate mofetil (up to 2 g/day) for the first 12 weeks after transplantation. GSK126 research buy Antibody induction was prohibited during the study. The primary efficacy end point was post-transplantation virologic response (pTVR), defined as HCV-RNA level less than the lower limit of quantification (LLOQ, 25 IU/mL) at 12 weeks post-transplant in patients who had HCV-RNA levels less than the LLOQ at their last assessment before transplantation. According to the original study analysis plan, only patients who received at least 12 weeks of treatment before transplantation were to be included in the efficacy analysis. However, this restriction was not used in the analysis, therefore the efficacy population includes patients who received any duration of treatment (Table 2 shows the overall results for both populations). Other secondary efficacy end points included an evaluation of safety and tolerability. Plasma HCV-RNA levels were measured with the COBAS TaqMan HCV

Test, version 2.0, for use with the High Pure System (Roche Molecular Systems). Population sequencing Romidepsin concentration of the HCV NS5B-encoding region of the viral polymerase was performed using standard sequencing technology on all baseline (pretreatment) viral samples. Deep sequencing with an assay cut-off Montelukast Sodium value of 1% was performed for all patients who qualified for resistance testing as a result of an incomplete virologic response on treatment, post-treatment relapse, post-transplant recurrence, or early termination with HCV-RNA levels greater than 1000 IU/mL. Nucleoside inhibitor-associated variants were defined as N142T, L159F, L230F, and V321A, and any substitutions at position S282 of NS5B. Drug susceptibility testing was performed using a replicon system with either patient population samples or site-directed mutants. Assuming an observed week 12 pTVR rate of 50%, we calculated that a sample size

of 31 would be sufficient to show that the 1-sided 95% upper bound of the confidence interval (using a normal approximation of the binomial) for the recurrence rate would be 65%. See the Supplementary Appendix for a detailed description of the statistical methods. The study was approved by the institutional review board or independent ethics committees at participating sites and was conducted in compliance with the Declaration of Helsinki, Good Clinical Practice guidelines, and local regulatory requirements. The study was designed and conducted according to protocol by the sponsor (Gilead) in collaboration with the principal investigators. The sponsor collected the data, monitored study conduct, and performed the statistical analyses.