The impact of IL2ra induction therapy in kidney transplantation using tacrolimus- and mycophenolate-based immunosuppression

Basiliximab vs. No Induction Therapy in Kidney Transplant Recipients with a Low Immunological Risk Profile Receiving Tacrolimus/Mycophenolate/Steroids Maintenance Immunosuppression

Background: Induction therapy with basiliximab is recommended in kidney transplant (KT) recipients with a low immunological risk (LIR) profile. Whether basiliximab is associated with a decreased risk of acute rejection (AR) and graft loss is controversial. Methods: In our institution, LIR patients (absence of anti-HLA antibodies before KT) are inducted with basiliximab in case of living-donor KT, while deceased-donor KT recipients receive no induction. Maintenance immunosuppression is similar, including a combination of tacrolimus (Tac), mycophenolate (MPA) and steroids. In this single-center retrospective study, we included all adult LIR patients who underwent KT between 1 January 2015 and 31 December 2022. Results: Of the 471 patients included, 354 received no induction and 117 received basiliximab. The median (IQR) number of HLA A-B-DR mismatches was 3 (2-3) and 2 (2-4) in the no induction group and the basiliximab group, respectively. The cumulative incidences in the no induction group vs. the basiliximab group of acute rejection and graft loss over 5 years post-KT were similar at 8.9% vs. 7.8% (p = 0.8) and 8.5% vs. 4.2% (p = 0.063), respectively. In multivariable Cox regression analysis, delayed graft function emerged as an independent risk factor for acute rejection (hazard ratio [HR] 2.75, 95% confidence interval [CI] 1.23-6.13, p = 0.014) and graft loss (HR 9.32, CI 4.10-21.1, p < 0.001). Conclusions: Basiliximab did not provide any advantage in terms of rate of acute rejection and graft survival within 5 years post KT compared with a strategy without induction therapy in patients with a low immunological risk profile receiving triple maintenance immunosuppression Tac/MPA/steroids.

Role of Induction in a Haplomatch, Related, Low-Risk, Living-Donor Kidney Transplantation with Triple Drug Immunosuppression: A Single-Center Study

BACKGROUND

The role of induction in low-risk, living-donor kidney transplants being treated with tacrolimus, mycophenolate mofetil, and prednisolone is debatable.

MATERIALS AND METHODS

This was a retrospective study that consisted of patients undergoing living kidney transplantation between February 2010 and June 2021 with a related haplomatch donor, with maintenance immunosuppression of tacrolimus, mycophenolate mofetil, and prednisolone. High-risk transplants, such as second or more transplants, immunologically incompatible transplants, and steroid-free transplants, were excluded. Patients were divided into three groups: no induction, basiliximab induction, and thymoglobulin induction, and the outcomes of all three were compared.

RESULTS

A total of 350 transplants were performed. There was a significant difference in the recipient sex distribution (P = 0.0373) and the number of preemptive transplants (P = 0.0272) between the groups. Other parameters were comparable. Biopsy-proven acute rejection (BPAR) was significantly less frequent in the thymoglobulin group than in the no-induction (5.3% vs. 17.5%; P = 0.0051) or basiliximab (5.3% vs. 18.8%; P = 0.0054) group. This persisted even after we performed multivariate regression analysis (thymoglobulin vs. no-induction group, P = 0.0146; thymoglobulin vs. basiliximab group, P = 0.0237). There was no difference in BPAR between the basiliximab and no-induction groups. There were no differences in other outcomes between the groups.

CONCLUSION

In a low-risk haplomatch, related, living-donor kidney transplant on tacrolimus, mycophenolate mofetil, and prednisolone, BPAR was significantly lower with thymoglobulin as opposed to no induction or basiliximab induction with a similar short-term patient and death-censored graft survival and infection rates. Basiliximab did not provide any benefit over no induction.

The impact of induction therapy in low-immunological risk kidney transplant recipients regardless of HLA matching

BACKGROUND

Induction agents have proved to reduce the rate of acute rejection (AR) in kidney transplant recipients (KTRs) without improving long-term graft and patient survival (PS).

OBJECTIVE

This study evaluates the utility of induction therapy in low immunological risk KTRs regardless of donor-to-recipient HLA matching.

METHODS

We retrospectively reviewed the records of 218 patients undergoing kidney transplantation (KT). These patients were divided into two groups according to the usage of induction therapy: 82 did not receive any induction therapy (Group I), and 136 patients received either Anti-IL2 receptor antibodies or anti-thymocyte globulin (Group II). All patients had panel reactive antibody (PRA) < 20% and absence of donor-specific antibodies (DSA). The difference in outcomes were assessed at different intervals following KT.

RESULTS

The rate of bacterial infections at one year (p-value = 0.032) and the frequency of CMV disease (p-value = 0.044) were significantly higher in Group II (with induction therapy). The duration of hospital stay, the rate and severity of acute rejection, the occurrence of delayed graft function, the rate and type of surgical complications at one year, and the graft function and survival at one and three years were similar between the two groups (p-value = NS). In addition, the financial burden is much less in Group I (without induction therapy), reducing the total cost of the transplant procedure.

CONCLUSION

We conclude that induction therapy in low-immunological risk kidney transplant patients is not a must regardless of donor-to-recipient HLA matching. Therefore, induction therapy did not yield significant health results, but had negative financial consequences.

Induction Therapy and Outcomes following Kidney Transplantation in Recipients of Previous Heart or Liver Transplants

INTRODUCTION

Optimal induction for kidney transplantation in patients with previous nonrenal organ transplantation is unclear. We aimed to evaluate the impact of induction therapy on the outcomes following kidney transplantation in patients who underwent prior heart or liver transplantation.

METHODS

Using the UNOS database, patients who underwent isolated heart or liver transplant from 2000 to 2016 followed by subsequent kidney transplant and maintained on calcineurin inhibitor (CNI)/mycophenolic acid (MPA) regimen were identified and stratified into three groups according to the induction used for kidney transplant: No induction, induction with interleukin-2 receptor antibody (IL-2RA), or T-cell depleting induction with Thymoglobulin. The outcomes were compared between no induction vs. IL-2RA and T-cell depleting induction, and IL-2RA vs. T-cell depleting induction.

RESULTS

Adjusted risk for delayed graft function was significantly higher for T-cell depleting vs. no induction (OR 4.56, 95% CI 1.14-18.3, P = 0.03) and trended higher for IL-2RA vs. no induction (OR 2.96, 95% CI 0.84-10.33, P = 0.08) among kidney after heart group and significantly higher for T-cell depleting vs. no induction (OR 2.88, 95% CI 1.40-5.95, P = 0.004) and IL-2RA induction (OR 1.88, 95% CI 1.12-3.17, P = 0.02) among kidney after liver patients. Adjusted graft failure and patient death risks were similar in patients who got IL-2RA or depleting inductions vs. no induction and IL-2RA vs. depleting induction groups in kidney after heart and kidney after liver groups.

CONCLUSIONS

The use of induction was not associated with graft or patient survival benefits for kidney transplantation in patients who had prior heart or liver transplants and maintained on CNI and MPA regimen.

Use and Outcomes of Induction Therapy in Well-Matched Kidney Transplant Recipients

BACKGROUND AND OBJECTIVES

The optimal induction treatment in low-immune risk kidney transplant recipients is uncertain. We therefore investigated the use and outcomes of induction immunosuppression in a low-risk cohort of patients who were well matched with their donor at HLA-A, -B, -DR, -DQB1 on the basis of serologic typing.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Our study was an observational study of first adult kidney-only transplant recipients in the United States recorded by the Organ Procurement and Transplant Network.

RESULTS

Among 2976 recipients, 57% were treated with T cell-depleting antibodies, 28% were treated with an IL-2 receptor antagonist, and 15% were treated without induction. There was no difference in allograft survival, death-censored graft survival, or death with function between patients treated with an IL-2 receptor antagonist and no induction therapy. In multivariable models, patients treated with T cell-depleting therapy had a similar risk of graft loss from any cause, including death (hazard ratio, 1.19; 95% confidence interval, 0.98 to 1.45), compared with patients treated with an IL-2 receptor antagonist or no induction. The findings were consistent in subgroup analyses of Black recipients, patients grouped by calculated panel reactive antibody, and donor source. The incidence of acute rejection at 1 year was low (≤5%) and did not vary between treatment groups.

CONCLUSIONS

Use of induction therapy with T cell-depleting therapy or IL-2 receptor antagonists in first kidney transplant recipients who are well matched with their donor at the HLA-A, -B, -DR, -DQB1 gene loci is not associated with improved post-transplant outcomes.

Induction Therapy and Therapeutic Antibodies

Prevention of allograft rejection is one of the crucial goals in solid organ transplantation to ensure durability of the graft and is chiefly mediated by cellular and humoral pathways targeting cell surface alloantigens. The risk of rejection is highest in the first post-transplant year and wanes with time albeit the risk always exists and varies with the type of organ transplanted. Induction therapies refer to the use of high-intensity immunosuppression in the immediate post-operative period to mitigate the highest risk of rejection. This term encompasses chiefly the use of antibody therapies directed against one of the key pathways in T-cell activation or abrogating effects of circulating alloantibodies. These antibodies carry more potent immunomodulatory effect than maintenance immunosuppressive therapy alone and many of them lead to durable immune cell depletion. A variety of monoclonal and polyclonal antibodies have been utilized for use not only for induction therapy, but also for treatment of allograft rejection when it occurs and as components of desensitization therapy before and after transplantation to modulate circulating alloantibodies.

Early Monitoring and Subsequent Gain of Tacrolimus Time-In-Therapeutic Range May Improve Clinical Outcomes After Living Kidney Transplantation

BACKGROUND

The early identification of recipients at high risk of graft loss is clinically relevant after kidney transplantation. The authors explored whether the earlier monitoring of tacrolimus (Tac) time-in-therapeutic range (TTR) is predictive of and a subsequent gain in TTR improves transplant outcomes.

METHODS

The TTR within 3, 6, 9, and 12 months was evaluated. Multivariate Cox analyses were performed to explore when TTR was predictive of transplant outcomes. Patients were divided into 3 groups based on incremental TTR change [TTR gain (increase >10%), TTR stable (maintained within 10%), and TTR loss (decrease >10%)] and 4 groups based on predefined cutoff values [low-low (LL), low-high (LH), high-low (HL), and high-high (HH)] using 6- and 12-month TTRs. Death-censored graft loss and patient death were primary outcomes.

RESULTS

Nonlinear associations were observed between 6-, 9-, and 12-month TTR and death-censored graft and patient survival rates. In multivariate analysis, every 10% increase in 6-, 9-, and 12-month TTRs was associated with reduced patient death [hazard ratio (HR): 0.83; HR: 0.68; HR: 0.61, respectively] and graft loss (HR: 0.88; HR: 0.73; HR: 0.66, respectively). A nonlinear relationship was observed between transplant outcomes and incremental changes in TTR. TTR gain and stable TTR contributed to higher graft survival (HR: 0.20; HR: 0.21) and patient survival (HR: 0.14; HR: 0.15) rates than TTR loss, whereas the former 2 had comparable outcomes. Furthermore, compared with those in the HH group, the LL and HL groups had inferior graft survival (HR: 3.33; HR: 5.17) and patient survival (HR: 5.15; HR: 8.94) rates, whereas the LH group had similar outcomes (P = 0.63, P = 0.97). Nonadherence was the main controllable risk factor for low TTR.

CONCLUSIONS

The 6-month TTR identified patients at higher risk of worse outcomes. The subsequent gain of TTR may contribute to better transplant outcomes.

The Management of Immunosuppression in Kidney Transplant Recipients with COVID-19 Disease: An Update and Systematic Review of the Literature

Background and Objectives: In the era of the coronavirus disease 2019 (COVID-19) pandemic, the management of immunosuppressive (IS) therapy in kidney transplant (KT) recipients affected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) requires attention. It is not yet understood whether IS therapy may protect from the cytokine storm induced by SARS-CoV-2 infection or a temporary adjustment/withdrawal of IS therapy to restore the immune system may be necessary. We performed a systematic literature review to investigate the current management of IS therapy in KT recipients with COVID-1. Materials and Methods: Out of 71 articles published from 1 February 2020 until 30 October 2020, 554 KT recipients with SARS-CoV-2 infection were identified. Results: Modifications of IS therapy were based on the clinical conditions. For asymptomatic patients or those with mild COVID-19 symptoms, a "wait and see approach" was mostly used; a suspension of antimetabolites drugs (347/461, 75.27%) or mTOR inhibitors (38/48, 79.2%) was adopted in the majority of patients with symptomatic COVID-19 infections. For CNIs, the most frequent attitude was their maintenance (243/502, 48.4%) or dose-reduction (99/502, 19.72%) in patients asymptomatic or with mild COVID-19 symptoms, while drug withdrawal was the preferred choice in severely symptomatic patients (160/450, 31.87%). A discontinuation of all IS drugs was used only in severely symptomatic COVID-19 patients on invasive mechanical ventilation. Renal function remained stable in 422(76.17%) recipients, while 49(8.84%) patients experienced graft loss. Eight (1.44%) patients experienced a worsening of renal function. The overall mortality was 21.84%, and 53(9.56%) patients died with functioning grafts. Conclusion: A tailored approach to the patient has been the preferred strategy for the management of IS therapy in KT recipients, taking into account the clinical conditions of patients and the potential interactions between IS and antiviral drugs, in the attempt to balance the risks of COVID-19-related complications and those due to rejection or graft loss.

Evidence of Interleukin-2-Receptor-Antibody Induction in Low-Risk Living Donor Kidney Transplantation: A Single-Center Pilot Study

BACKGROUND

The recommended standard immunosuppressive therapy for renal transplant recipients comprises an initial induction therapy mainly with an interleukin-2-receptor antibody (IL2-RA) and a triple maintenance therapy. With tacrolimus and mycophenolate acid it is unknown whether IL2-RA application affects the short- and long-term results. This question is addressed in the present analysis.

METHODS

From July 2007 to June 2019 a total of 127 living donor kidney transplant recipients meeting the center-specific definition of immunologic low risk situation (first transplantation, HLA-mismatch ≤3, panel reactive antibody ≤10%) were identified. In 83 recipients with a first-degree relationship to the donor we omitted the IL2-RA induction (IL2-RA-). The remaining 44 recipients, mostly not first-degree relatives, served as controls (IL2-RA+). Biopsy-proven acute rejection and long-term patient and graft survival rates were compared.

RESULTS

Biopsy-proven acute rejection rates after 3 months were similar in both groups with 4.8% (IL2-RA-) vs 13.7% (IL2-RA+; P = .0937), including borderline rejection rates of 18.0% (IL2-RA-) vs 18.3% (IL2-RA+; P = 1.000), respectively. Ten-year long-term survival rates were comparable between the IL2-RA- and the IL2-RA+ group with 95.6% vs 93.5% (patient survival; P = .5465) and 92.1% vs 90.6% (death-censored graft survival; P = .8893).

CONCLUSION

For low-risk living donor kidney transplant recipients with first-degree relationship to the donor, it is safe to omit induction therapy with IL2-RA.

Implication of interleukin-2 receptor antibody induction therapy in standard risk renal transplant in the tacrolimus era: a meta-analysis

Background

Interleukin-2 (IL-2) antagonist has been used as an induction therapy in many centres in calcineurin inhibitor-sparing regimens. Tacrolimus has overwhelmingly replaced cyclosporine in the maintenance immunosuppressive protocols in many transplant centres. The aim of our study and meta-analysis is to explore the effect of IL-2 induction therapy on the rate of rejection and patient and graft survival in standard-risk renal transplant patients with tacrolimus-based maintenance immunotherapy. Secondary aims included assessment of the effect of IL-2 induction therapy on creatinine change and the risk of cytomegalovirus (CMV) infection.

Methods

We conducted a systematic review in different databases to identify studies and research work that assessed the effect of IL-2 antibody induction therapy on renal transplant outcomes. Inclusion criteria for our meta-analysis were all studies that compared IL-2 induction therapy with placebo or no induction therapy in standard-risk renal transplant recipients on tacrolimus-based maintenance immunosuppressive therapy. Data collected were the name of the first author, journal title, year of publication, country where the study was conducted, number of patients in the IL-2 induction therapy arm and in the placebo arm, number of patients who had biopsy-proven rejection and graft survival in each arm. A random effects model was used for the meta-analysis.

Results

Of the 470 articles found in different databases, 7 were included in the meta-analysis. Forest plot analysis for rate of rejection during the follow-up period post-transplant showed no significant difference between the groups. There was no evidence of heterogenicity between included studies (I ² = 21.8%, P = 0.27). The overall risk difference was -0.02 [95% confidence interval (CI) -0.05-0.01]. A random effects meta-analysis for patient and graft survival was performed using forest plot analysis and showed no significant effect of IL-2 receptor (IL-2R) antibody induction on patient or graft survival compared with placebo. The overall risk difference was -0.01 (95% CI -0.04-0.01) and 0.00 (95% CI -0.00-0.01), respectively. Three of the included studies showed no effect of basiliximab on creatinine change, two showed no effect on risk of CMV infection and two showed less risk of post-transplant diabetes in the basiliximab group.

Conclusion

IL-2R antibody induction therapy has no significant effect on the rate of rejection or patient or graft survival in standard-risk renal transplant recipients on tacrolimus-based maintenance immunotherapy. More randomized controlled studies are needed.

A genetic link between CXCR5 and IL2RA gene polymorphisms and susceptibility to multiple sclerosis

OBJECTIVES

Multiple sclerosis (MS) is a T-cell-mediated disease of the central nervous system that develops in individuals possessing a complex susceptibility trait. We explored relationship between gene polymorphisms in MS.

METHODS

To identify the associations of CXCR5 and IL2RA gene polymorphisms with susceptibility to MS, we recruited 263 MS patients from the Han nationality and 138 from the Hui nationality as MS group and 284 healthy volunteers from the Han nationality and 156 from the Hui nationality as controls. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was employed to test gene polymorphisms of IL2RA (rs2104286 and rs12722489). Sequenom MassARRAY system was applied to analyze genotyping of CXCR5 (rs3922).

RESULTS

The genotypes and allele frequency distributions at the loci of IL2RA rs2104286 and rs12722489 showed significant differences between the MS and control groups. The gene polymorphisms at the loci of IL2RA rs2104286 and rs12722489 may increase the onset risk of MS. IL2RA-rs2104286 showed a positive relationship with CXCR5-rs3922. The same relationship was also observed between IL2RA-rs12722489 and CXCR5-rs3922. The genotypes and allele frequencies of loci of rs2104286 and rs12722489 were significantly different in MS clinical subtypes and severity (EDSS score). Additionally, CAC and TGC haplotype at rs3922-rs12722489-rs2104286 may reduce the risk of MS, while CGT and TGT haplotypes increase the risk.

CONCLUSION

The gene polymorphisms at the loci of IL2RA rs2104286 and rs12722489 are closely associated with susceptibility to MS in the Han and Hui nationalities.

Role of induction therapy in low immunological risk-kidney transplant recipients: A mate-kidney analysis

We aimed to evaluate the impact of induction on outcomes in low-immunological risk kidney transplant recipients (KTRs) using a mate-kidney model. Using OPTN/UNOS database, we identified three groups of low-immunological risk KTRs (first transplant, panel reactive antibody <20%, human leukocyte antigen mismatches ≤3) with each group containing recipients of mate-kidneys from same donor and differed by induction received: group 1: no induction vs interleukin-2 receptor antibody (IL2RA) induction; group 2: no induction vs depleting antibody induction; group 3: IL2RA vs depleting antibody induction. Outcomes were compared between mate-kidney recipients in each group in an adjusted model. Total of 1034 mate-kidney recipients were identified: group 1, n = 192; group 2, n = 362 and group 3, n = 480. Adjusted risk for DGF was higher (OR 1.89, 95% CI 1.09-3.25,.P = 0.02) and one-year acute rejection trended lower (OR 0.53, 95% CI 0.25-1.11, P = 0.09) among depleting antibody induced patients in group 2. Adjusted five-year graft survivals were similar between mate-kidney recipients in all three groups. Adjusted patient death risk was significantly lower in depleting antibody induced patients in group 2 (HR 0.48, 95% CI 0.26-0.88, P = 0.02) and trended lower in IL2RA induced patient in group 1 (HR 0.32, 95% CI 0.10-1.01, P = 0.05). Perioperative antibody induction was associated with lower patient death risk in low-immunologic risk KTRs.

Use of polyclonal/monoclonal antibody therapies in transplantation

INTRODUCTION

For over thirty years, antibody (mAb)-based therapies have been a standard component of transplant immunosuppression, and yet much remains to be learned in order for us to truly harness their therapeutic capabilities. Current mAbs used in transplant directly target and destroy graft-destructive immune cells, interrupt cytokine and costimulation-dependent T and B cell activation, and prevent down-stream complement activation. Areas covered: This review summarizes our current approaches to using antibody-based therapies to prevent and treat allograft rejection. It also provides examples of promising novel mAb therapies, and discusses the potential for future mAb development in transplantation. Expert opinion: The broad capability of antibodies, in parallel with our growing ability to synthetically modulate them, offers exciting opportunities to develop better biologic therapeutics. In order to do so, we must further our understanding about the basic biology underlying allograft rejection, and gain better appreciation of how characteristics of therapeutic antibodies affect their efficacy.

Induction Therapy for Kidney Transplant Recipients: Do We Still Need Anti-IL2 Receptor Monoclonal Antibodies?

Induction therapy with antilymphocyte biological agents is widely used after kidney transplantation, most commonly T lymphocyte-depleting rabbit-derived antithymocyte globulin (rATG) or an IL-2 receptor antagonist (IL2RA). Early randomized trials showed that rATG or IL2RA induction reduces early acute rejection, prompting recommendations by Kidney Disease Improving Global Outcomes that IL2RA induction be used routinely in first-line therapy after kidney transplantation, with lymphocyte-depleting induction reserved for high-risk cases. These studies, however, mainly used outdated maintenance regimens. No large randomized trial has examined the effect of IL2RA or rATG induction versus no induction in patients receiving tacrolimus, mycophenolic acid and steroids. With this triple maintenance therapy, the addition of induction may achieve an absolute risk reduction for acute rejection of only 1-4% in standard-risk patients without improving graft or patient survival. In contrast, rATG induction lowers the relative risk of acute rejection by almost 50% versus IL2RA in patients with high immunological risk. These recent data raise questions about the need for IL2RA in kidney transplantation, as it may no longer be beneficial in standard-risk transplantation and may be inferior to rATG in high-risk situations. Updated evidence-based guidelines are necessary to support clinicians deciding whether and what induction therapy is required for their transplant patients today.

Acute Rejection Rates and Graft Outcomes According to Induction Regimen among Recipients of Kidneys from Deceased Donors Treated with Tacrolimus and Mycophenolate

BACKGROUND AND OBJECTIVES

IL-2 receptor antagonist (IL2-RA) is recommended as a first-line agent for induction therapy in renal transplantation. However, this remains controversial in deceased donor renal transplantation (DDRT) maintained on tacrolimus (TAC)/mycophenolic acid (MPA) with or without steroids.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We studied the United Network for Organ Sharing Registry for patients receiving DDRT from 2000 to 2012 maintained on TAC/MPA at transplantation hospital discharge (n=74,627) to compare outcomes of IL2-RA and other induction agents. We initially divided the cohort into two groups on the basis of steroid use at the time of discharge: steroid (n=59,010) versus no steroid (n=15,617). Each group was stratified into induction categories: IL2-RA, rabbit antithymocyte globulin (r-ATG), alemtuzumab, and no induction. The main outcomes were incidence of acute rejection within the first year and overall graft failure (defined as graft failure and/or death) post-transplantation. Propensity score (PS), specifically inverse probability of treatment weight, analysis was used to minimize selection bias caused by nonrandom assignment of induction therapies.

RESULTS

Median (25th, 75th percentiles) follow-up times were 3.9 (1.1, 5.9) and 3.2 (1.1, 4.9) years for steroid and no steroid groups, respectively. Acute rejection within the first year and overall graft failure within 5 years of transplantation were more common in the no induction category (13.3%; P<0.001 and 28%; P=0.01, respectively) in the steroid group and the IL2-RA category (11.1%; P=0.16 and 27.4%; P<0.001, respectively) in the no steroid group. Compared with IL2-RA, PS-weighted and covariate-adjusted multivariable logistic and Cox analyses showed that outcomes in the steroid group were similar among induction categories, except that acute rejection was significantly lower with r-ATG (odds ratio [OR], 0.68; 95% confidence interval [95% CI], 0.62 to 0.74). In the no steroid group, compared with IL2-RA, odds of acute rejection with r-ATG (OR, 0.80; 95% CI, 0.60 to 1.00) and alemtuzumab (OR, 0.68; 95% CI, 0.53 to 0.88) were lower, and r-ATG was associated with better graft survival (hazard ratio, 0.86; 95% CI, 0.75 to 0.99).

CONCLUSIONS

In DDRT, compared with IL2-RA induction, no induction was associated with similar outcomes when TAC/MPA/steroids were used. r-ATG seems to offer better graft survival over IL2-RA in steroid avoidance protocols.

Basiliximab induction in kidney transplantation with donation after cardiac death donors

Basiliximab is a monoclonal antibody that binds to the α-chain of the interleukin (IL)-2 receptor. It is used as induction therapy in kidney transplantation. The objective of the present study was to evaluate induction therapy with single-dose basiliximab (Simulect^®) in kidney transplantation with donation after cardiac death (DCD) donors. A total of 33 DCD kidney transplants were performed between December 2010 and July 2013 in patients who received single-dose basiliximab (20 mg) as induction therapy. The maintenance immunosuppression included calcineurin inhibitor (cyclosporine A or tacrolimus), mycophenolate mofetil and corticosteroids. The follow-up time was 1 year. The mean ages of the DCD donors and recipients were 29.3 and 41.1 years, respectively. Within the 1-year follow-up, the overall incidence of acute rejection was 9.1%. There were 10 cases of delayed graft function among the recipients. Mean serum creatinine values at 1 week and at 1, 3, 6, 9 and 12 months post-transplantation were 257.6, 238.2, 194.5, 159.3, 137.9 and 110.8 µmol/l, respectively, with a favorable trend to allograft function recovery over time. The 1-year patient and graft survival rates were 96.9 and 90.9%, respectively, with an infection rate of 24.2%. Increased alanine aminotransferase/aspartate transaminase levels in only 2 patients were considered to be associated with basiliximab. This experience with single-dose basiliximab for induction therapy in DCD kidney transplantation showed that favorable clinical outcomes were achieved in terms of graft survival and function within 1 year.

Immunosuppressive Medications

Immunosuppressive agents are commonly used in the nephrologist's practice in the treatment of autoimmune and immune-mediated diseases and transplantation, and they are investigational in the treatment of AKI and ESRD. Drug development has been rapid over the past decades as mechanisms of the immune response have been better defined both by serendipity (the discovery of agents with immunosuppressive activity that led to greater understanding of the immune response) and through mechanistic study (the study of immune deficiencies and autoimmune diseases and the critical pathways or mutations that contribute to disease). Toxicities of early immunosuppressive agents, such as corticosteroids, azathioprine, and cyclophosphamide, stimulated intense investigation for agents with more specificity and less harmful effects. Because the mechanisms of the immune response were better delineated over the past 30 years, this specialty is now bestowed with a multitude of therapeutic options that have reduced rejection rates and improved graft survival in kidney transplantation, provided alternatives to cytotoxic therapy in immune-mediated diseases, and opened new opportunities for intervention in diseases both common (AKI) and rare (atypical hemolytic syndrome). Rather than summarizing clinical indications and clinical trials for all currently available immunosuppressive medications, the purpose of this review is to place these agents into mechanistic context together with a brief discussion of unique features of development and use that are of interest to the nephrologist.

Induction Therapies in Live Donor Kidney Transplantation on Tacrolimus and Mycophenolate With or Without Steroid Maintenance

BACKGROUND AND OBJECTIVES

Induction therapy with IL-2 receptor antagonist (IL2-RA) is recommended as a first line agent in living donor renal transplantation (LRT). However, use of IL2-RA remains controversial in LRT with tacrolimus (TAC)/mycophenolic acid (MPA) with or without steroids.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The Organ Procurement and Transplantation Network registry was studied for patients receiving LRT from 2000 to 2012 maintained on TAC/MPA at discharge (n=36,153) to compare effectiveness of IL2-RA to other induction options. The cohort was initially divided into two groups based on use of maintenance steroid at time of hospital discharge: steroid (n=25,996) versus no-steroid (n=10,157). Each group was further stratified into three categories according to commonly used antibody induction approach: IL2-RA, rabbit anti-thymocyte globulin (r-ATG), and no-induction in the steroid group versus IL2-RA, r-ATG and alemtuzumab in the no-steroid group. The main outcomes were the risk of acute rejection at 1 year and overall allograft failure (graft failure or death) post-transplantation through the end of follow-up. Propensity score-weighted regression analysis was used to minimize selection bias due to non-random assignment of induction therapies.

RESULTS

Multivariable logistic and Cox analysis adjusted for propensity score showed that outcomes in the steroid group were similar between no-induction (odds ratio [OR], 0.96; 95% confidence interval [95% CI], 0.86 to 1.08 for acute rejection; and hazard ratio [HR], 0.99; 95% CI, 0.90 to 1.08 for overall allograft failure) and IL2-RA categories. In the no-steroid group, odds of acute rejection with r-ATG (OR, 0.73; 95% CI, 0.59 to 0.90) and alemtuzumab (OR, 0.53; 95% CI, 0.42 to 0.67) were lower; however, overall allograft failure risk was higher with alemtuzumab (HR, 1.27; 95% CI, 1.03 to 1.56) but not with r-ATG (HR, 1.19; 95% CI, 0.97 to 1.45), compared with IL2-RA induction.

CONCLUSIONS

Compared with no-induction therapy, IL2-RA induction was not associated with better outcomes when TAC/MPA/steroids were used in LRT recipients. r-ATG appears to be an acceptable and possibly the preferred induction alternative for IL2-RA in steroid-avoidance protocols.

The risk of acute rejection and the influence of induction agents in lower-risk African American kidney transplant recipients receiving modern immunosuppression

BACKGROUND

While kidney transplant recipients of African American (AA) descent are frequently considered at increased risk of acute rejection, the value of induction therapy is not defined in settings of lower immunologic risk and modern immunosuppression.

METHODS

Using the Scientific Registry of Transplant Recipients database, we identified 23,244 primary kidney transplant recipients with panel-reactive antibody (PRA) = 0% treated with TAC/MPA and prednisone from 2000 to 2008. We compared acute rejection, graft survival (GS), and patient survival rates among AA and non-AA and further stratified by induction therapy (none, IL2ra, or rATG).

RESULTS

One-yr acute rejection was higher in AA than in non-AA overall (14.5% vs. 9.9%, hazard ratio [HR] for acute rejection [AR] 1.43, p < 0.0001) and was higher regardless of induction agent use. Induction therapy was associated with a reduction in AR, but no benefit in GS in AA or non-AA. In AA, rATG (adjusted relative risk [RR] 0.81, CI 0.70-0.94) and IL2ra (adjusted RR 0.80, CI 0.68-0.93) were similarly effective in reducing AR rates, but did not reach comparable outcomes as in non-AA.

CONCLUSION

African Americans who are at otherwise lower immunologic risk have a higher risk of rejection despite modern immunosuppression. Depleting or non-depleting induction therapy similarly reduces but does not entirely mitigate this increased risk, with no impact on three-yr GS.

Selection of induction therapy in kidney transplantation

Currently available immunosuppressive agents can be classified into three categories: induction agents, maintenance therapy, and treatment for rejection. This review article will focus on induction immunosuppression. There are three antibodies which are used for induction therapy: the lymphocyte-depleting agents - anti-thymocyte globulin and alemtuzumab, and basiliximab which is nondepleting. Historically, immunosuppressant selection was solely based on efficacy for prevention of rejection. In the current era of transplantation, it is now common practice in the transplant community to select induction therapy on the basis of risk-benefit considerations for each patient. This article will focus on the efficacy of available induction agents and the selection of induction agent based on donor and recipient risk factors.

Multivariate analysis of antibody induction therapy and their associated outcomes in live donor kidney transplantation in the recent era

The majority of kidney transplant recipients in the United States receive antibody induction, but its impact on outcomes in living donor transplant is not well-described. We used Organ Procurement and Transplant Network/United Network for Organ Sharing (OPTN/UNOS) data as of November 2009 to compare acute rejection (AR) and graft survival among all primary adult living donor kidney recipients of no antibody induction, antithymocyte globulin (ATG) and interleukin-2 receptor antagonists (IL-2RA) in an earlier era (1998-2002; n=21,919) and a later era (2003-2008, n=26,837). The incidence of AR in the overall cohort decreased from 18.5% in 1998 to 8% in 2008. From 1998 to 2002, antibody induction was associated with a decreased risk of acute rejection at six months (RR 0.67, 95% CI 0.62-0.72) and one yr (RR 0.71, 0.65-0.76), while in the recent era, induction was not associated with acute rejection at six months (RR 0.97, 0.88-1.07) or one yr (RR 1.01, 0.91-1.10). There was no difference in graft survival over five yr with antibody induction in either era. Although antibody induction was associated with a decreased risk of AR from 1998 to 2002, it was not associated with a decreased risk of acute rejection from 2003 to 2008, nor was it associated with a difference in graft survival in either era.

Endorsement of the Kidney Disease Improving Global Outcomes (KDIGO) guidelines on kidney transplantation: a European Renal Best Practice (ERBP) position statement

KDIGO (Kidney Disease: Improving Global Outcomes) is an international independent body aiming to 'improve the care and outcomes of kidney disease patients worldwide, through the development and implementation of clinical practice guidelines'. Recently, the KDIGO work group has produced comprehensive clinical practice guidelines for the care of kidney transplant recipients (KTRs). The guideline makes recommendations for immunosuppression, graft monitoring, as well as prevention and treatment of infection, cardiovascular disease, malignancy and other complications that are common in KTRs, including haematological and bone disorders. Because most guidelines were 'soft' rather than 'strong', and because global guidelines need to be adapted and implemented into the regional context where they are used, the European Renal Best Practice (ERBP) Advisory Board appointed a work group of transplant nephrologists and surgeons to review the newest KDIGO guideline and comment on its relevance and applicability for European KTRs. In this article, we concentrate only on those guidelines which we considered worth amending or adapting. All guidelines not mentioned are fully endorsed.