Conversion from twice-daily to once-daily tacrolimus does not reduce intrapatient variability in tacrolimus exposure.

BACKGROUND: Intrapatient variability (IPV) in tacrolimus exposure is associated with renal allograft failure. The aim of this study was to investigate whether conversion from the twice-daily tacrolimus formulation (Tac-TD) to a once-daily formulation (Tac-OD) leads to a lower IPV in tacrolimus exposure. METHODS: Two hundred forty-seven stable renal transplant recipients were converted from Tac-TD to Tac-OD (Advagraf) on a 1:1-mg total daily dose basis. After conversion, patients were followed for 12 months and tacrolimus predose whole-blood concentrations (C0), serum creatinine, estimated glomerular filtration rate, and proteinuria were measured. These parameters were compared with those collected at all outpatient visits in the 12-month period (±3 months) before conversion (Tac-TD period). The IPV was calculated based on the dose-adjusted tacrolimus C0. RESULTS: The Tac-OD formulation provided an excellent graft survival (100%), a low acute rejection rate (0.8%), and good tolerability. Renal function remained stable: estimated glomerular filtration rate 48 (16-90) versus 46 (12-90) mL/min (P = 0.15) before and after conversion, respectively. After conversion to Tac-OD, mean C0 was significantly lower, decreasing from 5.7 ± 1.5 to 5.0 ± 1.5 ng/mL, corresponding to a 12% reduction (P < 0.01). Both drugs had similar IPVs (Tac-TD: 17.3% ± 1.6% versus Tac-OD: 16.4% ± 1.6%, P = 0.31). CONCLUSIONS: Although conversion from Tac-TD to Tac-OD significantly reduces tacrolimus exposure as measured by C0 and seems safe, it does not reduce IPV in tacrolimus exposure.

Exploring health literacy and self-management after kidney transplantation: A prospective cohort study.

OBJECTIVE: Investigate the influence of health literacy and self-management on complications, kidney function and graft failure after kidney transplantation. METHODS: We included patients who received a kidney transplant between May 2012 and May 2013 and monitored outcomes until December 2018. Health literacy was measured using the Newest Vital Sign and self-management using the Partner in Health scale (before discharge, and after 6 and 12 months). Subscales are aftercare & knowledge, coping, recognition and management of symptoms, healthy lifestyle. Complications were categorized as rejection, viral infections, and bacterial infections. Kidney function was measured using eGFR and graft survival using days until failure. RESULTS: We included 154 patients. Higher health literacy at baseline and at 12 months was related to more viral infections (p = 0.02; p < 0.01). Lower 'coping' at baseline was related to more bacterial infections (p = 0.02). Higher 'after-care and knowledge' at 6 months (p < 0.01), and 'recognition and management of symptoms' at 6 months were associated with lower graft failure (p < 0.01). CONCLUSION: Health literacy did not influence kidney transplant related outcomes. Higher knowledge and management of symptoms were related to lower graft failure. PRACTICE IMPLICATIONS: Self-management support is a key focus for health care providers in the multidisciplinary team.

A Randomized Controlled Clinical Trial Comparing Belatacept With Tacrolimus After De Novo Kidney Transplantation.

BACKGROUND: Belatacept, an inhibitor of the CD28-CD80/86 costimulatory pathway, allows for calcineurin-inhibitor free immunosuppressive therapy in kidney transplantation but is associated with a higher acute rejection risk than ciclosporin. Thus far, no biomarker for belatacept-resistant rejection has been validated. In this randomized-controlled trial, acute rejection rate was compared between belatacept- and tacrolimus-treated patients and immunological biomarkers for acute rejection were investigated. METHODS: Forty kidney transplant recipients were 1:1 randomized to belatacept or tacrolimus combined with basiliximab, mycophenolate mofetil, and prednisolone. The 1-year incidence of biopsy-proven acute rejection was monitored. Potential biomarkers, namely, CD8CD28, CD4CD57PD1, and CD8CD28 end-stage terminally differentiated memory T cells were measured pretransplantation and posttransplantation and correlated to rejection. Pharmacodynamic monitoring of belatacept was performed by measuring free CD86 on monocytes. RESULTS: The rejection incidence was higher in belatacept-treated than tacrolimus-treated patients: 55% versus 10% (P = 0.006). All 3 graft losses, due to rejection, occurred in the belatacept group. Although 4 of 5 belatacept-treated patients with greater than 35 cells CD8CD28 end-stage terminally differentiated memory T cells/µL rejected, median pretransplant values of the biomarkers did not differ between belatacept-treated rejectors and nonrejectors. In univariable Cox regressions, the studied cell subsets were not associated with rejection-risk. CD86 molecules on circulating monocytes in belatacept-treated patients were saturated at all timepoints. CONCLUSIONS: Belatacept-based immunosuppressive therapy resulted in higher and more severe acute rejection compared with tacrolimus-based therapy. This trial did not identify cellular biomarkers predictive of rejection. In addition, the CD28-CD80/86 costimulatory pathway appeared to be sufficiently blocked by belatacept and did not predict rejection.

Inhibitory effect of tacrolimus on p38 mitogen-activated protein kinase signaling in kidney transplant recipients measured by whole-blood phosphospecific flow cytometry.

BACKGROUND: Tacrolimus (TAC), the cornerstone of immunosuppressive therapy after solid organ transplantation, inhibits calcineurin activation. Despite pharmacokinetic monitoring, patients frequently experience toxicity or lack of efficacy, which could be prevented by pharmacodynamic monitoring. In Jurkat T-cell lines, it has been shown that TAC, in addition to calcineurin, inhibits the p38 mitogen-activated protein kinase (MAPK) pathway, which is important in T-cell activation and is therefore a potential drug-specific biomarker. We studied whether TAC inhibits p38 MAPK signaling in primary human T cells and ex vivo in healthy volunteers and kidney transplant recipients. METHODS: Phorbol-12-myristate-13-acetate/ionomycin-induced MAPK signaling was measured by whole-blood phosphospecific flow cytometry. RESULTS: In vitro, 10-ng/mL TAC inhibited p38 MAPK phosphorylation by a mean of 27% in CD3, 26% in CD4, and 34% in CD8 T cells (P<0.01 compared with baseline). In healthy adults (n=4), 2 hr after a single oral dose of 10-mg TAC, the p38 MAPK activation was inhibited by 35% in CD3, CD4, and CD8 T cells (P<0.05 compared with baseline). In kidney transplant recipients (n=24), TAC predose concentrations (range, 3.2-10.5 ng/mL) were inversely correlated with p38 MAPK activation in CD3, CD4, and CD8 T cells (r=0.51, 0.34, and 0.37, respectively; P<0.01). CONCLUSIONS: TAC inhibits activation of the MAPK pathway in a dose-dependent manner in kidney transplant patients and may be a potential marker for immune monitoring.