Long-term exposure to belatacept in recipients of extended criteria donor kidneys

Conversion from calcineurin inhibitor-based immunosuppression to mammalian target of rapamycin inhibitors or belatacept in renal transplant recipients

The calcineurin inhibitors (CNIs) remain the standard of care for maintenance immunosuppression following renal transplantation. CNIs have demonstrated their effectiveness in reducing acute cellular rejection; however, some evidence suggests that these compounds negatively affect native renal function and are associated with allograft injury in renal transplant recipients. CNIs have also been linked with hypertension, new-onset diabetes after transplantation, tremor, and thrombotic microangiopathy, which have significant consequences for long-term allograft function and patient health overall. Thus, converting patients to a non-CNI-based regimen may improve renal function and also provide extrarenal benefits. A number of studies have been conducted that explore CNI conversion strategies in renal transplant recipients in an effort to improve long-term allograft function and survival. These include converting to alternative, non-nephrotoxic, maintenance immunosuppressants, such as the mammalian target of rapamycin inhibitors (sirolimus and everolimus) and the costimulation blocker belatacept. In this review of literature, evidence for the potential renal and extrarenal benefits of conversion to these non-CNI-based regimens is evaluated. Clinical challenges, including the adverse event profiles of non-CNI-based regimens and the selection of candidates for conversion, are also examined.

A network meta-analysis of the efficacy of belatacept, cyclosporine and tacrolimus for immunosuppression therapy in adult renal transplant recipients

Belatacept is a first in-class co-stimulation blocker developed for primary maintenance immunosuppression following renal transplantation. The objective of this study was to estimate the efficacy of belatacept relative to tacrolimus and cyclosporine among adults receiving a single kidney transplant. A systematic review was conducted of randomized clinical trials (RCTs) published between January 1990 and December 2013 using EMBASE, MEDLINE, the Cochrane Central Register of Controlled Trials, and unpublished study reports from two belatacept RCTs. Bayesian network meta-analysis (NMA) methods were used to compare the efficacy measures, mortality, graft loss, acute rejection and glomerular filtration rate (GFR). Heterogeneity was quantified using statistical metrics and potential sources were evaluated using meta-regression and subgroup analysis. A total of 28 RCTs comparing tacrolimus with cyclosporine, and three comparing belatacept with cyclosporine, were identified. All three agents provided comparable graft and patient survival, despite a higher risk of acute rejection associated with belatacept and cyclosporine. Belatacept was associated with significant improvement in GFR versus cyclosporine. Compared with tacrolimus, this difference was clinically meaningful yet statistically non-significant. The probability of being the best treatment was highest for belatacept for graft survival (68%), patient survival (97%) and renal function (89%), and highest for tacrolimus for acute rejection (99%).Variability in donor, recipient, and trial characteristics was present in the included RCTs; however, minimal statistical heterogeneity was detected in the analysis of acute rejection, graft or patient survival, and none of the characteristics were found to be significantly associated with relative effect. Although the direction of effect of immunosuppressants on GFR was consistent across RCTs, precise estimation of its magnitude was limited by a small number of RCTs and heterogeneity in relative effect sizes. Clinicians often seek an alternative to CNIs due to their nephrotoxic effects. The results of this indirect comparison indicate that belatacept is an effective immunosuppressive agent in renal transplantation among adults.

Beneficial effect of conversion to belatacept in kidney-transplant patients with a low glomerular-filtration rate

Belatacept has been found to be efficient at preserving good kidney function in maintenance kidney-transplant patients. Herein, we report on the use of belatacept as a rescue therapy for two kidney-transplant patients presenting with severe adverse events after treatment with calcineurin inhibitors (CNIs) and mammalian target-of-rapamycin (mTOR) inhibitors. Two kidney-transplant patients developed severely impaired kidney function after receiving CNIs. The use of everolimus was associated with severe angioedema. Belatacept was then successfully used to improve kidney function in both cases, even though estimated glomerular-filtration rate before conversion was <20 mL/min. These case reports show that belatacept can be used as a rescue therapy, even if kidney function is very low in kidney-transplant patients who cannot tolerate CNIs and/or mTOR inhibitors.