Everolimus-based immunosuppression in a case of ABO-incompatible liver transplantation with calcineurin inhibitor-related posterior occipital syndrome

Modification of immunosuppressive therapy as risk factor for complications after liver transplantation

Management of complications post-liver transplantation (LT) includes immunosuppressive manipulations with the aim to reduce the overall burden of immunologic suppression and compensate for renal, cardiovascular, metabolic toxicities, and for the increased oncologic risk. Two approaches can be implemented to reduce immunosuppression-related adverse events: upfront schedules tailored to the pretransplant individual patient's risk profile versus downstream modifications in the event of immunosuppression-related complications. Upfront strategies are supported by evidence originating from prospective randomized trials and consist of triple/quadruple schedules whereby calcineurin inhibitors (CNI)-exposure is reduced with combination of anti-CD25 monoclonal antibodies, antimetabolites and corticosteroids. Quadruple regimens allow for staggering of CNI introduction and higher renal function in the early term, but their superiority in the long term has not yet been established. A more recent upfront schedule contemplates early (4 weeks) introduction of mammalian target of rapamycin inhibitor (mTORi) everolimus and allows for reduction of CNI up to 4 years posttransplantation. Incorporation of mTORi has the potential to prolong time to recurrence for patients with hepatocellular carcinoma. However, as suggested by the available evidence, downstream immunosuppressive manipulations are more frequently adopted in clinical practice. These encompass CNI replacement and immunosuppression withdrawal. Switching CNI to mTORi monotherapy is the option most commonly adopted to relieve renal function and compensate for posttransplant malignancies. Its impact is dependent on interval from transplantation and underlying severity of renal impairment. Introduction of mTORi is associated with longer overall survival for patients with extrahepatic posttransplant malignancies, but results are awaited for recurrences of hepatocellular carcinoma. Immunosuppression withdrawal seems feasible (70%) in very long term survivors (>10 years), but is not associated with reversal of immunosuppression-related complications. Awaiting novel immunosuppressive drug categories, integration of upfront strategies with the aim to reduce CNI-exposure and a low threshold for adjustment in the posttransplant course are both advisable to improve long-term outcomes of LT.

Everolimus with early withdrawal or reduced-dose calcineurin inhibitors improves renal function in liver transplant recipients: A systematic review and meta-analysis

Calcineurin inhibitors (CNI) are the mainstay of immunosuppression after liver transplantation (LT), but CNIs are associated with significant nephrotoxicity. Recently, mTOR inhibitors such as sirolimus and everolimus (EVR) have been used with or without CNIs in LT recipients for their renal-sparing effect. We conducted a systematic review and meta-analysis of randomized controlled trials (RCT) that examined the effect of EVR with CNI minimization or withdrawal on renal function in LT recipients. RCT of primary adult LT recipients with baseline GFR >30 mL/min who received EVR with CNI minimization or withdrawal were included. Four RCTs (EVR n=465, control n=428) were included. In three RCTs, EVR was initiated 4 weeks following LT; these studies were used to assess the primary outcome. All four studies were used to assess the secondary outcomes. Based on this study, EVR use with CNI minimization in LT recipients is associated with improved renal function at 12 months by GFR of 10.2 mL/min (95% CI: 2.75-17.8). EVR use was not associated with an increased risk of biopsy-proven acute rejection (RR 0.68, 95% CI: 0.31-1.46), graft loss (RR 1.60, 95% CI: 0.51-5.00), or mortality (RR 1.34, 95% CI 0.62-2.90). However, it was associated with an increased risk of overall infections (RR 1.45, 95% CI: 1.10-1.91).

Pilot conversion trial from mycophenolic acid to everolimus in ABO-incompatible kidney-transplant recipients with BK viruria and/or viremia

Immunosuppression using everolimus (EVR) plus low-dose tacrolimus (Tac) is commonly used in organ transplantation. EVR has potential antiviral effects. Herein, the long-term outcomes and impacts of Tac-EVR on the BK virus are reported in ABO-incompatible kidney-transplant recipients. The initial immunosuppressive regimen combined steroids, Tac, and mycophenolic acid (MPA). At a median of 141 (34-529) days post-transplantation, seven stable ABO-incompatible kidney-transplant recipients were converted from MPA to EVR because of active BK replication, and compared with a reference group of fourteen ABO-incompatible patients receiving classical Tac plus MPA. At 1 month before conversion, at 1, 3 months after, and at last follow-up, clinical and biological parameters were monitored. The median time from conversion to the last follow-up was 784 (398-866) days. Conversion to EVR caused no change to rejection episodes or immunological status (isoagglutinin titers, anti-HLA antibodies). At last follow-up, median eGFR was similar in the Tac-MPA versus Tac-EVR group (40 [range: 14-56] vs. 54.5 ml/min/1.73 m(2) [range: 0-128], P = 0.07). The major adverse event was dyslipidemia. Interestingly, conversion from MPA to EVR decreased BK viral load in five patients. ABO-incompatible kidney-transplant recipients with an active BK virus infection may benefit from conversion to EVR.

Strategies to overcome the ABO barrier in kidney transplantation

Kidney transplantation across the ABO blood group barrier was long considered a contraindication for transplantation, but in an effort to increase donor pools, specific regimens for ABO-incompatible (ABOi) transplantation have been developed. These regimens are now widely used as an integral part of the available treatment options. Various desensitization protocols, commonly based on transient depletion of preformed anti-A and/or anti-B antibodies and modulation of B-cell immunity, enable excellent transplant outcomes, even in the long-term. Nevertheless, the molecular mechanisms behind transplant acceptance facilitated by a short course of anti-humoral treatment are still incompletely understood. With the evolution of efficient clinical programmes, tailoring of recipient preconditioning based on individual donor-recipient blood type combinations and the levels of pretransplant anti-A/B antibodies has become possible. In the context of low antibody titres and/or donor A2 phenotype, immunomodulation and/or apheresis might be dispensable. A concern still exists, however, that ABOi kidney transplantation is associated with an increased risk of surgical and infectious complications, partly owing to the effects of extracorporeal treatment and intensified immunosuppression. Nevertheless, a continuous improvement in desensitization strategies, with the aim of minimizing the immunosuppressive burden, might pave the way to clinical outcomes that are comparable to those achieved in ABO-compatible transplantation.

Multiple indications for everolimus after liver transplantation in current clinical practice

AIM: To assess our experience with the use and management of everolimus-based regimens post-liver transplantation and to redefine the potential role of this drug in current clinical practice.

METHODS: From October 1988 to December 2012, 1023 liver transplantations were performed in 955 patients in our Unit. Seventy-four patients (7.74%) received immunosuppression with everolimus at some time post-transplantation. Demographic characteristics, everolimus indication, time elapsed from transplantation to the introduction of everolimus, doses and levels administered, efficacy, side effects, discontinuation and post-conversion survival were analyzed.

RESULTS: Mean age at the time of conversion to everolimus was 57.7 ± 10 years. Indications for conversion were: refractory rejection 31.1%, extended hepatocellular carcinoma in explanted liver 19%, post-transplant hepatocellular carcinoma recurrence 8.1%, de novo tumour 17.6%, renal insufficiency 8.1%, severe neurotoxicity 10.8%, and others 5.4%. Median time from transplantation to introduction of everolimus was 6 mo (range: 0.10-192). Mean follow-up post-conversion was 22 ± 19 mo (range: 0.50-74). The event for which the drug was indicated was resolved in 60.8% of patients, with the best results in cases of refractory rejection, renal insufficiency and neurotoxicity. Results in patients with cancer were similar to those of a historical cohort treated with other immunosuppressants. The main side effects were dyslipidemia and infections. Post-conversion acute rejection occurred in 14.9% of cases. The drug was discontinued in 28.4% of patients.

CONCLUSION: Everolimus at low doses in combination with tacrolimus is a safe immunosuppressant with multiple early and late indications post-liver transplantation.