A randomized, double-blind trial of basiliximab immunoprophylaxis plus triple therapy in kidney transplant recipients

The Effect of Induction Therapy on Antibody-Mediated Rejection in Kidney Transplantation: A Network Meta-Analysis Using Recent Data

BACKGROUND

Various induction regimens are available for kidney transplantation (KT); however, which is superior remains unclear. Moreover, although the induction regimens are effective and important for reducing side effects, their respective relationships with antibody-mediated rejection (AMR) after transplantation remain unclear. Therefore, this study aimed to elucidate the most effective induction regimen for AMR reduction through network analysis.

METHODS

We performed a comprehensive search of databases, including basiliximab, alemtuzumab, antithymocyte globulin (ATG), and daclizumab as induction regimens for KT from inception to September 1, 2022. Using a network meta-analysis, we investigated the priorities of 5 induction regimens for patient survival, graft failure, and graft rejection after ABO-incompatible KT.

RESULTS

In total, 25 studies comprising 1768 people were included in this network meta-analysis. The primary outcome was the AMR rate of other induction regimens compared with that of basiliximab, whereas the secondary outcomes were heart failure, stroke, hospitalization, peripheral artery disease, myocardial infarction, anemia, leukopenia, herpes zoster, or adverse events. Notably, ATG reduced the AMR rate by 59% (odds ratio, 0.41; 95% credible interval, 0.20-0.90), whereas the other drugs did not show statistical significance. Furthermore, secondary outcomes did not significantly differ between the induction regimens.

CONCLUSION

ATG is widely used in KT induction regimens. Our results showed that ATG reduced the risk of AMR in KT recipients when compared with other induction drugs; therefore, it appears to be an efficient choice of induction regimen to reduce AMR after KT.

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 and maintenance immunosuppression in pediatric kidney transplantation-Advances and controversies

Advances in immunosuppression have improved graft survival in pediatric kidney transplant recipients; however, treatment-related toxicities need to be balanced against the possibility of graft rejection. Several immunosuppressive agents are available for use in transplant recipients; however, the optimal combinations of agents remain unclear, resulting in variations in institutional protocols. Lymphocyte-depleting antibodies, specifically ATG, are the most common induction agent used for pediatric kidney transplantation in the US. Basiliximab may be used for induction in immunologically low-risk children; however, pediatric data are scarce. CNIs and antiproliferative agents (mostly Tac and mycophenolate in recent years) constitute the backbone of maintenance immunosuppression. Steroid-avoidance maintenance regimens remain controversial. Belatacept and mTOR inhibitors are used in children under specific circumstances such as non-adherence or CNI toxicity. This article reviews the indications, mechanism of action, efficacy, dosing, and side effect profiles of various immunosuppressive agents available for pediatric kidney transplantation.

Randomized trial of steroid free immunosuppression with basiliximab induction in adult live donor liver transplantation (LDLT)

BACKGROUND

Corticosteroids are an integral part of immunosuppression following solid organ transplantation, despite their metabolic complications. We conducted a randomized trial to evaluate the efficacy of steroid-free immunosuppression following live donor liver transplantation (LDLT).

METHODS

We randomized 104 patients stratified based on pre-transplant diabetic status to either a steroid-free arm (SF-arm) (Basiliximab + Tacrolimus and Azathioprine,n = 52) or Steroid arm (S-Arm) (Steroid + Tacrolimus + Azathioprine,n = 52). The primary endpoint was the occurrence of metabolic complications (new-onset diabetes after transplant (NODAT), new-onset systemic hypertension after transplant (NOSHT), post-transplant dyslipidemia) within 6 months after transplant. Secondary endpoints included biopsy-proven acute rejection (BPAR) within six months, patient and graft survival at 6 months.

RESULTS

The incidence NODAT was significantly higher in S-arm at 3 months (64.5%vs. 28.1%,p-0.004) and 6 months (51.6% vs. 15.6%,p-0.006). Likewise, the incidence of NOSHT (27.8% vs. 4.8%,p-0.01) and hypertriglyceridemia (26.7% vs. 8%,p-0.03) at six months was significantly higher in S-arm. However, there were no differences in BPAR (19.2% vs. 21.2%, p-0.81), time to first rejection (58 vs. 53 days, p-0.78), patient and graft survival (610 vs. 554 days,p- 0.22).

CONCLUSION

Following LDLT, basiliximab induction with tacrolimus and azathioprine maintenance resulted in significantly lower metabolic complications compared to the triple-drug regimen of steroid, tacrolimus, and azathioprine.

Infectious Complications of Biological and Small Molecule Targeted Immunomodulatory Therapies

The past 2 decades have seen a revolution in our approach to therapeutic immunosuppression. We have moved from relying on broadly active traditional medications, such as prednisolone or methotrexate, toward more specific agents that often target a single receptor, cytokine, or cell type, using monoclonal antibodies, fusion proteins, or targeted small molecules. This change has transformed the treatment of many conditions, including rheumatoid arthritis, cancers, asthma, and inflammatory bowel disease, but along with the benefits have come risks. Contrary to the hope that these more specific agents would have minimal and predictable infectious sequelae, infectious complications have emerged as a major stumbling block for many of these agents. Furthermore, the growing number and complexity of available biologic agents makes it difficult for clinicians to maintain current knowledge, and most review articles focus on a particular target disease or class of agent. In this article, we review the current state of knowledge about infectious complications of biologic and small molecule immunomodulatory agents, aiming to create a single resource relevant to a broad range of clinicians and researchers. For each of 19 classes of agent, we discuss the mechanism of action, the risk and types of infectious complications, and recommendations for prevention of infection.

Transitional changes in the incidence of hip osteonecrosis among renal transplant recipients

BACKGROUND

Immunosuppressive therapy for renal allograft recipients has changed substantially since the introduction of the anti-CD25 monoclonal antibody, basiliximab. We hypothesized that recent improvements in immunosuppressive treatment may reduce the incidence of osteonecrosis of the femoral head (ONFH). This study aimed to investigate transitional changes in the incidence of OFNH among renal transplant recipients by MRI.

METHODS

Participants comprised 110 patients who had undergone renal transplantation from 2003 to 2012, during which time basiliximab was in regular use at our institute (Recent group), and 232 patients who had undergone RT between 1986 and 2003 (Past group). We compared ONFH incidence between the two groups and evaluated risk factors for ONFH, including immunosuppressants (calcineurin inhibitors, basiliximab, and/or steroids) and postoperative renal function.

RESULTS

Incidence of ONFH was lower in the Recent group (0%) than in the Past group (3.4%; p = 0.043). In the Recent group, age was greater, ABO/human leukocyte antigen incompatibility was worse, while steroid dose was decreased and post-transplant renal function was improved. Cumulative methylprednisolone dose at postoperative week 2 and delayed graft function were identified as risk factors for ONFH.

CONCLUSION

Risk of ONFH after renal transplantation has fallen with the advent of regular use of basiliximab, although this agent does not appear to be a factor directly associated with the incidence of ONFH.

STUDY DESIGN

Clinical prognostic study (Level III case control study).

Pulmonary Infections in Immunocompromised Hosts: Clinical

Pulmonary infections in immunocompromised patients remain a significant contributor to mortality, morbidity, and health care-associated costs in such a vulnerable patient population. Their epidemiology is changing, set forth by new trends in immunosuppressive regimens and also prophylaxis. The host characteristics, presenting clinical symptomatology, along with radiographic patterns, have also evolved. The microbiology diagnostics are now enriched with nonculture methods for better identification of the causative pathogens. Chest imaging remains the cornerstone of the initial workup. Our article will examine the new trends in epidemiology, clinical findings, and diagnostics for immunocompromised patients with pulmonary infections (transplant recipients, neutropenic hosts, HIV-infected patients, and patients with autoimmune conditions). We will also review the differential diagnosis that most of the times includes malignancies and drug or radiation-related toxicities.

Immunosuppressive therapy for kidney transplantation in adults: a systematic review and economic model

BACKGROUND

End-stage renal disease is a long-term irreversible decline in kidney function requiring renal replacement therapy: kidney transplantation, haemodialysis or peritoneal dialysis. The preferred option is kidney transplantation, followed by immunosuppressive therapy (induction and maintenance therapy) to reduce the risk of kidney rejection and prolong graft survival.

OBJECTIVES

To review and update the evidence for the clinical effectiveness and cost-effectiveness of basiliximab (BAS) (Simulect(®), Novartis Pharmaceuticals UK Ltd) and rabbit anti-human thymocyte immunoglobulin (rATG) (Thymoglobulin(®), Sanofi) as induction therapy, and immediate-release tacrolimus (TAC) (Adoport(®), Sandoz; Capexion(®), Mylan; Modigraf(®), Astellas Pharma; Perixis(®), Accord Healthcare; Prograf(®), Astellas Pharma; Tacni(®), Teva; Vivadex(®), Dexcel Pharma), prolonged-release tacrolimus (Advagraf(®) Astellas Pharma), belatacept (BEL) (Nulojix(®), Bristol-Myers Squibb), mycophenolate mofetil (MMF) (Arzip(®), Zentiva; CellCept(®), Roche Products; Myfenax(®), Teva), mycophenolate sodium (MPS) (Myfortic(®), Novartis Pharmaceuticals UK Ltd), sirolimus (SRL) (Rapamune(®), Pfizer) and everolimus (EVL) (Certican(®), Novartis) as maintenance therapy in adult renal transplantation.

METHODS

Clinical effectiveness searches were conducted until 18 November 2014 in MEDLINE (via Ovid), EMBASE (via Ovid), Cochrane Central Register of Controlled Trials (via Wiley Online Library) and Web of Science (via ISI), Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects and Health Technology Assessment (The Cochrane Library via Wiley Online Library) and Health Management Information Consortium (via Ovid). Cost-effectiveness searches were conducted until 18 November 2014 using a costs or economic literature search filter in MEDLINE (via Ovid), EMBASE (via Ovid), NHS Economic Evaluation Database (via Wiley Online Library), Web of Science (via ISI), Health Economic Evaluations Database (via Wiley Online Library) and the American Economic Association's electronic bibliography (via EconLit, EBSCOhost). Included studies were selected according to predefined methods and criteria. A random-effects model was used to analyse clinical effectiveness data (odds ratios for binary data and mean differences for continuous data). Network meta-analyses were undertaken within a Bayesian framework. A new discrete time-state transition economic model (semi-Markov) was developed, with acute rejection, graft function (GRF) and new-onset diabetes mellitus used to extrapolate graft survival. Recipients were assumed to be in one of three health states: functioning graft, graft loss or death.

RESULTS

Eighty-nine randomised controlled trials (RCTs), of variable quality, were included. For induction therapy, no treatment appeared more effective than another in reducing graft loss or mortality. Compared with placebo/no induction, rATG and BAS appeared more effective in reducing biopsy-proven acute rejection (BPAR) and BAS appeared more effective at improving GRF. For maintenance therapy, no treatment was better for all outcomes and no treatment appeared most effective at reducing graft loss. BEL + MMF appeared more effective than TAC + MMF and SRL + MMF at reducing mortality. MMF + CSA (ciclosporin), TAC + MMF, SRL + TAC, TAC + AZA (azathioprine) and EVL + CSA appeared more effective than CSA + AZA and EVL + MPS at reducing BPAR. SRL + AZA, TAC + AZA, TAC + MMF and BEL + MMF appeared to improve GRF compared with CSA + AZA and MMF + CSA. In the base-case deterministic and probabilistic analyses, BAS, MMF and TAC were predicted to be cost-effective at £20,000 and £30,000 per quality-adjusted life-year (QALY). When comparing all regimens, only BAS + TAC + MMF was cost-effective at £20,000 and £30,000 per QALY.

LIMITATIONS

For included trials, there was substantial methodological heterogeneity, few trials reported follow-up beyond 1 year, and there were insufficient data to perform subgroup analysis. Treatment discontinuation and switching were not modelled.

FUTURE WORK

High-quality, better-reported, longer-term RCTs are needed. Ideally, these would be sufficiently powered for subgroup analysis and include health-related quality of life as an outcome.

CONCLUSION

Only a regimen of BAS induction followed by maintenance with TAC and MMF is likely to be cost-effective at £20,000-30,000 per QALY.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42014013189.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Immunosuppressive therapy for kidney transplantation in children and adolescents: systematic review and economic evaluation

BACKGROUND

End-stage renal disease is a long-term irreversible decline in kidney function requiring kidney transplantation, haemodialysis or peritoneal dialysis. The preferred option is kidney transplantation followed by induction and maintenance immunosuppressive therapy to reduce the risk of kidney rejection and prolong graft survival.

OBJECTIVES

To systematically review and update the evidence for the clinical effectiveness and cost-effectiveness of basiliximab (BAS) (Simulect,(®) Novartis Pharmaceuticals) and rabbit antihuman thymocyte immunoglobulin (Thymoglobuline,(®) Sanofi) as induction therapy and immediate-release tacrolimus [Adoport(®) (Sandoz); Capexion(®) (Mylan); Modigraf(®) (Astellas Pharma); Perixis(®) (Accord Healthcare); Prograf(®) (Astellas Pharma); Tacni(®) (Teva); Vivadex(®) (Dexcel Pharma)], prolonged-release tacrolimus (Advagraf,(®) Astellas Pharma); belatacept (BEL) (Nulojix,(®) Bristol-Myers Squibb), mycophenolate mofetil (MMF) [Arzip(®) (Zentiva), CellCept(®) (Roche Products), Myfenax(®) (Teva), generic MMF is manufactured by Accord Healthcare, Actavis, Arrow Pharmaceuticals, Dr Reddy's Laboratories, Mylan, Sandoz and Wockhardt], mycophenolate sodium, sirolimus (Rapamune,(®) Pfizer) and everolimus (Certican,(®) Novartis Pharmaceuticals) as maintenance therapy in children and adolescents undergoing renal transplantation.

DATA SOURCES

Clinical effectiveness searches were conducted to 7 January 2015 in MEDLINE (via Ovid), EMBASE (via Ovid), Cochrane Central Register of Controlled Trials (via Wiley Online Library) and Web of Science [via Institute for Scientific Information (ISI)], Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects and Health Technology Assessment (HTA) (The Cochrane Library via Wiley Online Library) and Health Management Information Consortium (via Ovid). Cost-effectiveness searches were conducted to 15 January 2015 using a costs or economic literature search filter in MEDLINE (via Ovid), EMBASE (via Ovid), NHS Economic Evaluation Databases (via Wiley Online Library), Web of Science (via ISI), Health Economic Evaluations Database (via Wiley Online Library) and EconLit (via EBSCOhost).

REVIEW METHODS

Titles and abstracts were screened according to predefined inclusion criteria, as were full texts of identified studies. Included studies were extracted and quality appraised. Data were meta-analysed when appropriate. A new discrete time state transition economic model (semi-Markov) was developed; graft function, and incidences of acute rejection and new-onset diabetes mellitus were used to extrapolate graft survival. Recipients were assumed to be in one of three health states: functioning graft, graft loss or death.

RESULTS

Three randomised controlled trials (RCTs) and four non-RCTs were included. The RCTs only evaluated BAS and tacrolimus (TAC). No statistically significant differences in key outcomes were found between BAS and placebo/no induction. Statistically significantly higher graft function (p < 0.01) and less biopsy-proven acute rejection (odds ratio 0.29, 95% confidence interval 0.15 to 0.57) was found between TAC and ciclosporin (CSA). Only one cost-effectiveness study was identified, which informed NICE guidance TA99. BAS [with TAC and azathioprine (AZA)] was predicted to be cost-effective at £20,000-30,000 per quality-adjusted life year (QALY) versus no induction (BAS was dominant). BAS (with CSA and MMF) was not predicted to be cost-effective at £20,000-30,000 per QALY versus no induction (BAS was dominated). TAC (with AZA) was predicted to be cost-effective at £20,000-30,000 per QALY versus CSA (TAC was dominant). A model based on adult evidence suggests that at a cost-effectiveness threshold of £20,000-30,000 per QALY, BAS and TAC are cost-effective in all considered combinations; MMF was also cost-effective with CSA but not TAC.

LIMITATIONS

The RCT evidence is very limited; analyses comparing all interventions need to rely on adult evidence.

CONCLUSIONS

TAC is likely to be cost-effective (vs. CSA, in combination with AZA) at £20,000-30,000 per QALY. Analysis based on one RCT found BAS to be dominant, but analysis based on another RCT found BAS to be dominated. BAS plus TAC and AZA was predicted to be cost-effective at £20,000-30,000 per QALY when all regimens were compared using extrapolated adult evidence. High-quality primary effectiveness research is needed. The UK Renal Registry could form the basis for a prospective primary study.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42014013544.

FUNDING

The National Institute for Health Research HTA programme.

Pharmacologic targeting of regulatory T cells for solid organ transplantation: current and future prospects

The last three decades have witnessed significant advances in the development of immunosuppressive medications used in kidney transplantation leading to a remarkable gain in short-term graft function and outcomes. Despite these major breakthroughs, improvements in long-term outcomes lag behind due to a stalemate between drug-related nephrotoxicity and chronic rejection typically due to donor-specific antibodies. Regulatory T cells (Tregs) have been shown to modulate the alloimmune response and can exert suppressive activity preventing allograft rejection in kidney transplantation. Currently available immunosuppressive agents impact Tregs in the alloimmune milieu with some of these interactions being deleterious to the allograft while others may be beneficial. Variable effects are seen with common antibody induction agents such that basiliximab, an IL-2 receptor blocker, decreases Tregs while lymphocyte depleting agents such as antithymocyte globulin increase Tregs. Calcineurin inhibitors, a mainstay of maintenance immunosuppression since the mid-1980s, seem to suppress Tregs while mammalian targets of rapamycin (less commonly used in maintenance regimens) expand Tregs. The purpose of this review is to provide an overview of Treg biology in transplantation, identify in more detail the interactions between commonly used immunosuppressive agents and Tregs in kidney transplantation and lastly describe future directions in the use of Tregs themselves as therapy for tolerance induction.

Usefulness of Tacrolimus without Basiliximab in Well-Matched Living-Donor Renal Transplant Recipients in Korea

OBJECTIVES

Basiliximab is used alongside tacrolimus-based immunosuppression for routine induction therapy, even for well-matched living-donor renal transplant recipients. Because tacrolimus is a different drug from cyclosporine, this study examined the utility of tacrolimus-based immunosuppression without basiliximab for well-matched living-donor renal transplant recipients.

MATERIALS AND METHODS

This prospective study evaluated 36 patients who underwent 1 to 3 human leukocyte antigens mismatched living-donor renal transplants without basiliximab induction therapy between April 2012 and March 2015 (group 1). All transplants were ABO compatible and T-flow negative and were followed until April 2015. Tacrolimus-based triple therapy was used for maintenance immunosuppression. The control group comprised 72 age- and sex-matched patients who underwent 1 to 3 human leukocyte antigens mismatched living-donor renal transplants with basiliximab induction therapy during the same period (group 2).

RESULTS

Two patients in group 1 and 12 patients in group 2 had infection,with cytomegalovirus infection and Pneumocystis pneumonia infection occurring only in group 2 and BK virus and urinary tract infection reported in both groups, with a similar incidence. One patient from group 2 had sepsis. Although the incidence of infection tended to be lower in group 1 than in group 2 (5.6% vs 16.7%), the overall incidence of infection was not significantly different (P=.135). In addition, there were no significant differences in incidence of acute rejection between groups 1 and 2 (2.8% vs 4.2%; P=.699). All patients showed stable renal function after treatment.

CONCLUSIONS

Tacrolimus-based triple drug maintenance immunosuppression without basiliximab might be an optimal treatment choice for individuals undergoing well-matched living-donor renal transplant.

Blocking MHC class II on human endothelium mitigates acute rejection

Acute allograft rejection is mediated by host CD8⁺ cytotoxic T lymphocytes (CTL) targeting graft class I major histocompatibility complex (MHC) molecules. In experimental rodent models, rejection requires differentiation of naive CD8⁺ T cells into alloreactive CTL within secondary lymphoid organs, whereas in humans, CTL may alternatively develop within the graft from circulating CD8⁺ effector memory T cells (T_EM) that recognize class I MHC molecules on graft endothelial cells (EC). This latter pathway is poorly understood. Here, we show that host CD4⁺ T_EM, activated by EC class II MHC molecules, provide critical help for this process. First, blocking HLA-DR on EC lining human artery grafts in immunodeficient mice reduces CD8⁺ CTL development within and acute rejection of the artery by adoptively transferred allogeneic human lymphocytes. Second, siRNA knockdown or CRISPR/Cas9 ablation of class II MHC molecules on EC prevents CD4⁺ T_EM from helping CD8⁺ T_EM to develop into CTL in vitro. Finally, implanted synthetic microvessels, formed from CRISPR/Cas9-modified EC lacking class II MHC molecules, are significantly protected from CD8⁺ T cell-mediated destruction in vivo. We conclude that human CD8⁺ T_EM-mediated rejection targeting graft EC class I MHC molecules requires help from CD4⁺ T_EM cells activated by recognition of class II MHC molecules.

Effects of interleukin 2 receptor blockers on patient and graft survival in renal-transplanted children

Background:

Monoclonal antibodies block interleukin-2 receptors on alloantigen-reactive T-Lymphocytes and induce selective immunosuppression. It is postulated that induction therapy with these agents in pediatric transplantation may decrease acute rejection and improve graft survival with no significant side effect or increase in the incidence of viral infections.

Objectives:

The aim of this study was to examine the effects of interleukin 2 receptor blockers on patient and graft survival in renal-transplanted children.

Patients and Methods:

One hundred and eighty six children aged 7-13 years who received renal transplantation in university-affiliated hospital between 2003 and 2012 were enrolled in the study. All patients received prednisolone, cyclosporine and mycophenolate mofetil or azathioprine as basic immunosuppressive therapy. Patients were divided into two groups according to receiving induction therapy with IL2-receptor blockers. We investigated for acute rejection episodes, Cytomegalovirus (CMV) and BK virus infection and one and three year’s survival of the patients and the grafts

Results:

From 186 renal-transplanted children included in this study, 36 patients were in treated group (group 1) and 150 patients in control group (group 2). The mean age of the patients was 10.4 ± 2 years and 55.6% were males. In first six months of transplantation, eight patients in group one had one episode of acute rejection and no one had two episodes. Early acute rejection rate was 8.36 (22%). In the control group, 37 patients had one episode and three patients had two episodes of acute rejection (rejection rate 28.6%). Therefore, early acute rejection rates were lower in group one. Late acute rejection rates did not show any difference in group 1 and group 2 (27.7% vs. 27.3% respectively). There was lower prevalence of steroid-resistance rejection in group 1 patients (5.5%) compared with 6.6% in group 2, but it did not reach statistical significance. None of the patients in IL2-R blocker group died at one year follow-up (patient survival 100%). However, in control group, four (2.6%) patients died toward the end of first year (patient survival 97.4%). When patients in group 1 and group 2 were age and sex matched with equal number the difference was significant (P < 0.05).

Conclusions:

Induction therapy with IL2-R blockers reduced the rate of early acute rejection, but had no effect on late acute rejections. Patient and graft survival were better in treated group, but did not reach statistical significance. A longer period of follow-up may be required to discern a clear advantage for induction therapy with these agents.

Risk of serious opportunistic infections after solid organ transplantation: interleukin-2 receptor antagonists versus polyclonal antibodies. A meta-analysis

BACKGROUND

We aimed to evaluate and quantify the risk of serious opportunistic infections after induction with polyclonal antibodies versus IL-2 receptor antagonists (IL-2RAs) in randomized clinical trials.

METHODS

PRISMA guidelines were followed and random-effects models were performed.

RESULTS

70 randomized clinical trials (10,106 patients) were selected: 36 polyclonal antibodies (n = 3377), and 34 IL-2RAs (n = 6729). Compared to controls, polyclonal antibodies showed higher risk of serious opportunistic infections (OR: 1.93, 95% CI: 1.34-2.80; p < 0.0001); IL-2RAs were associated with lower risk of serious opportunistic infections (OR: 0.80, 95% CI: 0.68-0.94; p = 0.009). Polyclonal antibodies were associated with higher risk of bacterial (OR: 1.58, 95% CI: 1.00-2.50; p = 0.049) and viral infections (OR: 2.37, 95% CI: 1.60-3.49; p < 0.0001), while IL-2RAs were associated with lower risk of cytomegalovirus (CMV) disease (OR: 0.73, 95% CI: 0.56-0.97; p = 0.032). Adjusted indirect comparison: compared to polyclonal antibodies, IL-2RAs were associated with lower risk of serious opportunistic infections (OR: 0.41, 95% CI: 0.34-0.49; p < 0.0001), bacterial infections (OR: 0.51, 95% CI: 0.39-0.67; p < 0.0001) and CMV disease (OR: 0.58, 95% CI: 0.34-0.98; p = 0.043). Results remained consistent across allografts.

CONCLUSION

The risk of serious opportunistic infections, bacterial infections and CMV disease were all significantly decreased with IL-2RAs compared to polyclonal antibodies.

Efficacy of basiliximab induction in poorly matched living donor renal transplantation

Non-depleting antibody induction has the best safety profile in transplant recipients without an increased risk of infection or malignancy. This observational study was performed in intermediate immunologic risk live donor renal transplants to assess basiliximab efficacy in patients on tacrolimus, mycophenolate, and prednisolone immunosuppression. A total of 46 patients on basiliximab induction were compared to risk matched 56 controls at the end of 6 and 12 months post-transplant. An additional cost of approximately Rs. 100,000/patient was incurred by the basiliximab group. The incidence of biopsy proven acute rejection in the control group (12.5%, 6 months and 20.5%, 1 year) and the basiliximab group (13%, 6 months and 18.9%, 1 year) was similar. At 6 months, there was a non-significant trend toward more steroid sensitive rejections and better glomerular filtration rate preservation in the basiliximab group (83.3%, 71.9 ml/min) versus the control group (28.6%, 62.2 ml/min). However, this difference was lost at 1 year (70.1 ml/min vs. 67.6 ml/min). The incidence of infections was similar and none of the patients had a malignancy. Death censored graft survival (94.6% basiliximab and 94.8% control) and the mean number of hospitalizations for all reasons at the end of 1 year were not different among the two groups. In our study, basiliximab induction did not confer an additional advantage in the intermediate risk live donor transplants in patients on tacrolimus and mycophenolate based triple drug immunosuppression.

Basiliximab: efficacy and safety evaluation in kidney transplantation

INTRODUCTION

Basiliximab is a chimeric monoclonal antibody directed against the alpha chain of interleukin-2 receptor (IL-2R). When administered intravenously at a dosage of 20 mg at the time of transplantation and 4 days later, basiliximab saturates the alpha chain of IL-2R for 4 weeks.

AREAS COVERED

This review evaluates the efficacy and safety of basiliximab in kidney transplantation. Randomized controlled trials showed that basiliximab can significantly reduce the incidence of acute rejection without increasing the risk of adverse events. When compared with other antibodies used for induction, basiliximab showed efficacy and safety profiles similar to daclizumab, another monoclonal antibody directed against the alpha chain of IL-2R. In comparison with rabbit anti-thymocyte globulins (rATG), basiliximab showed a similar efficacy. However, in patients at higher risk of rejection, rATG proved to be more effective. No serious safety problems related to basiliximab have been reported.

EXPERT OPINION

There is a solid evidence that basiliximab can significantly decrease the risk of acute rejection in kidney transplant recipients without increasing adverse events. This can allow decreased dosage or avoidance of glucocorticoids and reduced dosage of calcineurin inhibitors. On the basis of efficacy, tolerability, ease of administration, and cost effectiveness, basiliximab may be considered the drug of choice for the prophylaxis of acute rejection in standard renal transplant recipients.

Current state of renal transplant immunosuppression: Present and future

For kidney transplant recipients, immunosuppression commonly consists of combination treatment with a calcineurin inhibitor, an antiproliferative agent and a corticosteroid. Many medical centers use a sequential immunosuppression regimen where an induction agent, either an anti-thymocyte globulin or interleukin-2 receptor antibody, is given at the time of transplantation to prevent early acute rejection which is then followed by a triple immunosuppressive maintenance regimen. Very low rejection rates have been achieved at many transplant centers using combinations of these agents in a variety of protocols. Yet, a large number of recipients suffer chronic allograft injury and adverse events associated with drug therapy. Regimens designed to limit or eliminate calcineurin inhibitors and/or corticosteroid use are actively being pursued. An ideal immunosuppressive regimen limits toxicity and prolongs the functional life of the graft. This article contains a critical analysis of clinical data on currently available immunosuppressive strategies and an overview of therapeutic moieties in development.

Current landscape for T-cell targeting in autoimmunity and transplantation

In recent years, substantial advances in T-cell immunosuppressive strategies and their translation to routine clinical practice have revolutionized management and outcomes in autoimmune disease and solid organ transplantation. More than 80 diseases have been considered to have an autoimmune etiology, such that autoimmune-associated morbidity and mortality rank as third highest in developed countries, after cardiovascular diseases and cancer. Solid organ transplantation has become the therapy of choice for many end-stage organ diseases. Short-term outcomes such as patient and allograft survival at 1 year, acute rejection rates, as well as time course of disease progression and symptom control have steadily improved. However, despite the use of newer immunosuppressive drug combinations, improvements in long-term allograft survival and complete resolution of autoimmunity remain elusive. In addition, the chronic use of nonspecifically targeted immunosuppressive drugs is associated with significant adverse effects and increased morbidity and mortality. In this article, we discuss the current clinical tools for immune suppression and attempts to induce long-term T-cell tolerance induction as well as much-needed future approaches to produce more short-acting, antigen-specific agents, which may optimize outcomes in the clinic.

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.

Long-term outcome of ATG vs. Basiliximab induction

BACKGROUND

An evaluation of the long-term efficacy and incidence of adverse events after induction therapy with antithymocyte globulin (ATG) vs. Basiliximab in renal transplant patients.

METHODS

Sixty recipients receiving ATG induction and a dual immunosuppression with Tacrolimus and steroids were compared retrospectively with 60 patients treated with Basiliximab. The following characteristics were evaluated: concomitant immunosuppression, recipient age, donor age, time on dialysis, cold ischemia time, year of transplantation and HLA mismatches.

RESULTS

The 6-year patient survival in the ATG group was 91·7% compared to 85% in the Basiliximab group (not significant, n.s.). Graft survival at 6 years was 89·7% and. 83·6% in the ATG and the Basiliximab group (n.s.), respectively. Incidence of biopsy proven acute rejection episodes (33·3% vs. 26·7%) and delayed graft function (30% vs. 33·3%) were similar in both groups. Kidney function was not significantly different at 1 and 6 years. CMV infections were more prevalent in the ATG arm (22% vs. 5%; P = 0·05), and a significantly higher rate of haematological complications was observed following ATG induction.

CONCLUSIONS

ATG induction was associated with an improved (but n.s.) trend in patient and graft survival. Patients induced with ATG had a higher rate of CMV infections and haematological complications.

Antibody immunosuppressive therapy in solid-organ transplant: Part I

Currently, a wide variety of both polyclonal and monoclonal antibodies are being routinely utilized to prevent and treat solid organ rejection. More commonly, these agents are also administered in order to delay introduction of calcineurin inhibitors, especially in patients with already compromised renal function. While these antibody therapies dramatically reduced the incidence of acute rejection episodes and improved both short and long-term graft survival, they are also associated with an increased incidence of opportunistic infections and neoplastic complications. Therefore, effective patient management must necessarily balance these risks against the potential benefits of the therapy.

Analytic Review: Neurological Complications of Transplantation

Recipients of solid organ or hematopoietic cell transplants are at risk of life-threatening neurological disorders including encephalopathy, seizures, infections and tumors of the central nervous system, stroke, central pontine myelinolysis, and neuromuscular disorders—often requiring admission to, or occurring in, the intensive care unit (ICU). Many of these complications are linked directly or indirectly to immunosuppressive therapy. However, neurological disorders may also result from graft versus host disease, or be an expression of the underlying disease which prompted transplantation, as well as injury induced during radiation, chemotherapy, surgery, and ICU stay. In rare cases, neuroinfectious pathogens may be transmitted with the transplanted tissue or organ. Diagnosis may be a challenge because clinical symptoms and findings on neuroimaging lack specificity, and a biological specimen or tissue diagnosis is often needed for definitive diagnosis. Management is centered on preventing further neurological injury, etiology-targeted therapy, and balancing the benefits and toxicities of specific immunosuppressive agents.

The role of basiliximab in the evolving renal transplantation immunosuppression protocol

Basiliximab is a chimeric mouse-human monoclonal antibody directed against the alpha chain of the interleukin-2 (IL-2) receptor on activated T lymphocytes. It was shown in phase III trials to reduce the number and severity of acute rejection episodes in the first year following renal transplantation in adults and children, with a reasonable cost-benefit ratio. The drug does not increase the incidence of opportunistic infections or malignancies above baseline in patients treated with conventional calcineurin inhibitor-based immunosuppression. In the field of renal transplantation, basiliximab does not increase kidney or patient survival, despite the reduction in the number of rejection episodes. Basiliximab may reduce the incidence of delayed graft function. In comparison with lymphocyte-depleting antibodies basiliximab appears to have equal efficacy in standard immunological risk patients. Recently, IL-2 receptor monoclonal antibodies have been used with the objective of reducing or eliminating the more toxic elements of the standard immunosuppression protocol. Several trials have incorporated basiliximab in protocols designed to avoid or withdraw rapidly corticosteroids, as well as protocols which substitute target-of-rapamycin (TOR) inhibitors for calcineurin inhibitors.

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

BACKGROUND

IL2 receptor antagonist (IL2ra) induction therapy has gained favor due to an excellent safety profile and improved outcomes in randomized trials using cyclosporine-based immunosuppression. However, there have been no large randomized trials or retrospective analyses examining the effect of IL2ra versus no induction using tacrolimus and mycophenolate (TAC/MPA)-based therapy.

METHODS

A retrospective analysis from the Scientific Renal Transplant Registry of adult, primary kidney transplant recipients from 2000 to 2008 with initial immunosuppression of TAC/MPA and prednisone, who received IL2ra induction therapy or no induction therapy (n=28,686) was performed. The primary outcome was acute rejection at 1 year, and secondary outcomes were graft and patient survival at 1 and 3 years. Multivariable analysis was used to control for factors shown to influence the incidence of acute rejection, and separate analyses were performed for deceased versus living donors.

RESULTS

Acute rejection at 1 year was significantly lower with IL2ra (11.6%) versus no induction therapy (13.0%; P=0.001). One-year (95.7% vs. 95.8%) and 3-year (87.5% vs. 87.8%) graft survival, and 1-year (97.4% vs. 97.5%) and 3-year (92.8% vs. 93.2%) patient survival, was not different between those receiving IL2ra and no induction therapy. On multivariable analysis, the relative risk of acute rejection with IL2ra was 0.90 (95% CI, 0.85-0.96; P=0.001), and the effect was greater in living donors (relative risk, 0.82; P<0.001) than deceased donors (relative risk, 0.95; P=0.23).

CONCLUSION

The benefit of IL2ra induction with TAC/MPA/prednisone maintenance immunosuppression is less than previously reported due to a low baseline incidence of acute rejection.

Interleukin-2 receptor antibody does not reduce rejection risk in low immunological risk or tacrolimus-treated intermediate immunological risk renal transplant recipients

AIM

The use of interleukin-2 receptor antibody (IL-2Ra) induction has been associated with reduced rejection rates in renal transplant recipients. However, the effect of IL-2Ra induction on graft and patient outcomes in renal transplant recipients with differing immunological risk remains unclear.

METHODS

Using Australia and New Zealand Dialysis and Transplant Registry, renal transplant recipients in Australia between 1995 and 2005 were included. Recipients were stratified into low immunological risk (primary grafts with < or = 2 human leucocyte antigen (HLA)-mismatches and panel-reactive antibody (PRA) < 10%) or intermediate immunological risk (subsequent grafts or >2 HLA-mismatches or PRA > 25%) recipients. Recipients receiving T-cell depletive induction therapy or steroid and/or calcineurin-free inhibitor regimens were excluded. Outcomes analysed included the presence of rejection at 6 months, estimated glomerular filtration rate at 1 and 5 years, graft and patient survival.

RESULTS

218 of 1220 (18%) low-risk and 883 of 3204 (28%) intermediate-risk recipients received IL-2Ra. In intermediate-risk recipients, IL-2Ra induction was associated with a 26% reduction in the incidence of acute rejection; but this benefit was restricted only to recipients initiated on cyclosporine-based immunosuppressive regimens. In contrast, the use of IL-2Ra in low-risk recipients was not associated with reduced rejection risk. There was no association between IL-2Ra induction and other graft or patient outcomes in both low- and intermediate-risk recipients.

CONCLUSION

This registry analysis suggests that IL-2Ra induction may be associated with a reduction in rejection risk in cyclosporine-treated intermediate immunological risk recipients, but not in low-risk renal transplant recipients.

Is there any role for antithymocyte induction in renal transplantation?

The use of an antibody induction agent in kidney transplantation lowers the risk of an acute rejection episode and may improve graft outcomes. Antithymocyte globulin (ATG) is the most commonly used antibody induction agent for kidney transplantation in the United States, despite its significant side effect profile and cost compared to the interleukin-2 receptor antagonists (IL2-RA). Our review suggests the IL2-RA are safe and well tolerated, and provide equal clinical benefit to ATG at a lower cost. We propose that there is insufficient evidence to justify the use of ATG induction in kidney transplantation.

Heterogeneity of induction therapy in Spain: changing patterns according to year, centre, indications and results

Background. The use of induction drugs has increased markedly over the last 15 years in the USA, but there are few data about their use in other countries. Moreover, there are not enough data about when they are indicated and their long-term effects. The aim of our study was to know the rates of use and the drugs used as induction therapy, in which patients they were prescribed and the long-term graft survival effect in Spain.

Methods. We conducted a retrospective cohort study with adult patients (4861) receiving a kidney allograft in Spain over four different years (1990, 1994, 1998 and 2002) with a functioning graft at the end of the first post-transplant year. Induction therapy was defined as when the patient received polyclonal antibodies, OKT3 monoclonal antibodies or anti-CD25 monoclonal antibodies.

Results. From 1990 to 2002, the use of induction therapy in Spain changed, with a progressive reduction in the use of OKT3 and an increasing use of anti-CD25 antibodies. There were great differences in the rate of induction use from one centre to another, although with a common trend to greater use at each centre. Induction therapy was mainly prescribed in patients with a higher rejection risk (higher panel reactive antibody (PRA) titres and mismatches and re-transplants) and in older and diabetic recipients. Lastly, patients who were treated with induction therapy had significant higher allograft survival than those who did not (P value = 0.035).

Conclusions. The use of induction therapy in Spain has changed, with an increasing use of monoclonal antibodies in recent years. Induction therapy has a protective role in long-term graft survival.

Interleukin 2 receptor antagonists for kidney transplant recipients

BACKGROUND

Interleukin 2 receptor antagonists (IL2Ra) are used as induction therapy for prophylaxis against acute rejection in kidney transplant recipients. Use of IL2Ra has increased steadily since their introduction, but the proportion of new transplant recipients receiving IL2Ra differs around the globe, with 27% of new kidney transplant recipients in the United States, and 70% in Australasia receiving IL2Ra in 2007.

OBJECTIVES

To systematically identify and summarise the effects of using an IL2Ra, as an addition to standard therapy, or as an alternative to another immunosuppressive induction strategy.

SEARCH STRATEGY

We searched the Cochrane Renal Group's specialised register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE to identify new records, and authors of included reports were contacted for clarification where necessary.

SELECTION CRITERIA

Randomised controlled trials (RCTs) in all languages comparing IL2Ra to placebo, no treatment, other IL2Ra or other antibody therapy.

DATA COLLECTION AND ANALYSIS

Data was extracted and assessed independently by two authors, with differences resolved by discussion. Dichotomous outcomes are reported as relative risk (RR) and continuous outcomes as mean difference (MD) with 95% confidence intervals (CI).

MAIN RESULTS

We included 71 studies (306 reports, 10,537 participants). Where IL2Ra were compared with placebo (32 studies; 5,784 patients) graft loss including death with a functioning graft was reduced by 25% at six months (16 studies: RR 0.75, 95% CI 0.58 to 0.98) and one year (24 studies: RR 0.75, 95% CI 0.62 to 0.90), but not beyond this. At one year biopsy-proven acute rejection was reduced by 28% (14 studies: RR 0.72, 95% CI 0.64 to 0.81), and there was a 19% reduction in CMV disease (13 studies: RR 0.81, 95% CI 0.68 to 0.97). There was a 64% reduction in early malignancy within six months (8 studies: RR 0.36, 95% CI 0.15 to 0.86), and creatinine was lower (7 studies: MD -8.18 micromol/L 95% CI -14.28 to -2.09) but these differences were not sustained.When IL2Ra were compared to ATG (16 studies, 2211 participants), there was no difference in graft loss at any time point, or for acute rejection diagnosed clinically, but the was benefit of ATG therapy over IL2Ra for biopsy-proven acute rejection at one year (8 studies:, RR 1.30 95% CI 1.01 to 1.67), but at the cost of a 75% increase in malignancy (7 studies: RR 0.25 95% CI 0.07 to 0.87) and a 32% increase in CMV disease (13 studies: RR 0.68 95% CI 0.50 to 0.93). Serum creatinine was significantly lower for IL2Ra treated patients at six months (4 studies: MD -11.20 micromol/L 95% CI -19.94 to -2.09). ATG patients experienced significantly more fever, cytokine release syndrome and other adverse reactions to drug administration and more leucopenia but not thrombocytopenia. There were no significant differences in outcomes according to cyclosporine or tacrolimus use, azathioprine or mycophenolate, or to the study populations baseline risk for acute rejection. There was no evidence that effects were different according to whether equine or rabbit ATG was used.

AUTHORS' CONCLUSIONS

Given a 38% risk of rejection, per 100 recipients compared with no treatment, nine recipients would need treatment with IL2Ra to prevent one recipient having rejection, 42 to prevent one graft loss, and 38 to prevent one having CMV disease over the first year post-transplantation. Compared with ATG treatment, ATG may prevent some experiencing acute rejection, but 16 recipients would need IL2Ra to prevent one having CMV, but 58 would need IL2Ra to prevent one having malignancy. There are no apparent differences between basiliximab and daclizumab. IL2Ra are as effective as other antibody therapies and with significantly fewer side effects.

Anti-interleukin-2 receptor antibodies-basiliximab and daclizumab-for the prevention of acute rejection in renal transplantation

The use of antibody induction after kidney transplantation has increased from 25% to 63% in the past decade and roughly one half of the induction agent used is anti-interleukin-2 receptor antibody (IL-2RA, ie, basiliximab or daclizumab). When combined with calcineurin inhibitor (CNI)-based immunosuppression, IL-2RAs have been shown to reduce the incidence of acute rejection, one of the predictors of poor graft survival, without increasing risks of infections and malignancies in kidney transplantation. For low-immunological-risk patients, IL-2RAs, as compared with lymphocyte-depleting antibodies, are equally efficacious and have better safety profiles. For high-risk patients, however, IL-2RAs may be inferior to lymphocyte-depleting antibodies for the prophylaxis of acute rejection. In an effort to reduce toxicities of other immunosuppressive medications without increasing the risk of acute rejection and chronic graft loss, IL-2RAs have often been combined with steroid- and CNI-sparing immunosuppression protocols. More data support the benefits of early steroid withdrawal with IL-2RA in low-risk patients, but preferred induction therapy for high-risk patients has yet to be determined. Although CNI-sparing protocols with IL-2RA may preserve renal function and improve long-term survival in selected patients, further studies are needed to identify those who benefit most from this strategy.

Efficacy and safety of basiliximab in pediatric renal transplant patients receiving cyclosporine, mycophenolate mofetil, and steroids

BACKGROUND

Basiliximab, a monoclonal CD25 antibody has proofed effective in reducing acute rejection episodes in adults in various immunosuppressive regimens. The effect of basiliximab in the pediatric population is controversial.

METHODS

In a 12-month, double-blind, placebo-controlled trial, renal transplant patients aged 1 to 18 years were randomized to basiliximab or placebo with cyclosporine microemulsion, mycophenolate mofetil, and corticosteroids. The intent-to-treat population comprised 192 patients (100 basiliximab and 92 placebo).

RESULTS

The primary efficacy endpoint, time to first biopsy-proven acute rejection episode, or treatment failure by month 6, occurred in 16.7% of basiliximab-treated patients and 21.7% of placebo-treated patients (Kaplan-Meier estimates; hazard ratio 0.72, two-sided 90% confidence interval 0.416-1.26, n.s.). The rate and severity of subclinical rejections in protocol biopsies performed at 6 months posttransplant was higher in the basiliximab group (25.0%) than in the placebo group (11.7%). Patient and death-censored graft survival at 12 months was 97% and 99%, respectively, in the basiliximab cohort, and 100% and 99% among placebo-treated patients (n.s.). Renal function was similar in both treatment groups, and there were no significant between-treatment differences in the incidence of adverse events or infections.

CONCLUSIONS

Addition of basiliximab induction to a regimen of cyclosporine microemulsion, mycophenolate mofetil, and steroids resulted in a numerically lower but not significant incidence of biopsy-proven acute rejection versus placebo and excellent graft and patient survival at 1 year in pediatric renal transplant recipients. Whether this numerical difference is a true therapeutic benefit in view of the higher rate and severity of subclinical rejections in the basiliximab group in the protocol biopsy will be investigated in a long-term follow-up study.

Induction immunosuppressive therapy in renal transplantation: does basiliximab make the difference?

The optimal prophylactic induction immunosuppressive therapy to prevent renal transplant rejection remains controversial. Recently, basiliximab efficiency has been reported in several studies. We sought to evaluate the efficiency of induction immunosuppressive therapy with basiliximab in renal transplantation in our unit based upon the acute rejection rate, patient and graft survivals, first hospital admission length, and incidence of infectious or malignant complications during 4 years of follow-up. We retrospectively evaluated the outcome of two groups of renal transplant recipients treated with triple immunosuppressive therapy (cyclosporine, mycophenolate mofetil, and prednisolone) without (group 1, 149 patients) or with (group 2, 104 patients) induction immunosuppression with basiliximab. The two groups did not differ in demographic characteristics, number of hypersensitized patients, cold ischemia time, or donor age. The group receiving basiliximab displayed a significantly lower acute rejection rate (7.6% vs 24%, P = .001) and shorter first hospital admission (14.4 +/- 8 vs 19.5 +/- 11 days). There was no difference in graft or patient survival, death due to sepsis, or incidence of posttransplant malignancies. Although there was no difference in graft or patient survival, immunosuppressive induction therapy with basiliximab yielded a significant reduction in the acute rejection rate.

Basiliximab versus daclizumab combined with triple immunosuppression in deceased donor renal graft recipients

In this prospective, randomized, open-label, single-center study, we compared the efficacy and safety of two anti-interleukin-2 receptor monoclonal antibodies among adult recipients of at least 1 HLA-mismatched deceased donor renal grafts. Eligible patients were randomized to induction with either basiliximab or daclizumab. Both groups received cyclosporine microemulsion (CsA Neoral), mycophenolate mofetil, and methylprednisolone. An intent-to-treat analysis of 1-year data assessed the incidence of acute rejection episodes, the renal graft function, the safety, and the patient and graft survivals. Among 127 patients, six (10.0%) and seven (11.5%) patients experienced biopsy-confirmed acute rejection at 12 months, in the basiliximab and the daclizumab groups, respectively. Two renal grafts were lost in the basiliximab and six in the daclizumab cohort, one of them due to rejection. One basiliximab and two daclizumab patients died. Hospital treatment was required for 25 and 33 infections in basiliximab and daclizumab groups, respectively. One basal cell carcinoma of skin was detected. One hypersensitivity reaction was observed with daclizumab. At 12 months, serum creatinine was 101+/-28 micromol/L with basiliximab and 109+/-41 micromol/L with daclizumab. Patient survival was 98.4% with basiliximab and 96.7% with daclizumab, and graft survival was 96.8% versus 90.8%, respectively. No significant differences were observed between the groups. Basiliximab or daclizumab combined with triple therapy was an efficient and safe immunosuppression strategy, demonstrated with low incidence of acute rejection episodes, an acceptable adverse event profile, excellent graft function, and high survival rates in adult recipients within the first year after deceased donor renal transplantation.

Induction therapy in pediatric renal transplant recipients: an overview

Induction therapy to prevent the acute rejection of mismatched allografts with the ultimate aim of prolonging the life of the allograft has been the cornerstone of immunosuppression since the introduction of renal transplantation. Agents used for induction therapy have changed over time. Their role in transplantation is expanding to include corticosteroid avoidance and immunosuppression minimization. This review provides an overview of induction therapies for renal transplantation including historic therapies such as total lymphoid irradiation and Minnesota antilymphocyte globulin, and current therapies with polyclonal and monoclonal antibodies and chemical agents, with special emphasis on children. Data from adult studies, and pediatric studies whenever available, are summarized. A brief summary of experimental therapies with fingolimod and belatacept is provided. Historically, induction therapies were targeted at T cells. The role of induction therapies targeted at B cells is emerging in select groups of patients that include highly sensitized recipients and those receiving transplants from blood group incompatible donors. With the advent of newer maintenance immunosuppressive medications and with very low rates of acute rejection, induction protocols for renal transplantation need to be targeted so that excessive immunosuppression and infections are avoided. Several single-center and registry data analyses in children suggest that the addition of an interleukin (IL)-2 receptor antagonist may improve graft survival compared with no induction. The safety profile of IL-2 receptor antagonists is indistinguishable from that of placebo, with no apparent difference in the incidence of infection or post-transplant lymphoproliferative disease. IL-2 receptor antagonists and polyclonal lymphocyte-depleting antibodies offer equivalent efficacy in standard-risk populations. However, in high-risk patients, acute rejection rates and graft outcomes may be improved with the use of lymphocyte-depleting agents such as Thymoglobulin. However, cytomegalovirus infection and other infections may be more common with this therapy. Therefore, in patients at high risk of graft loss, Thymoglobulin may be the preferred choice for induction therapy, while for all other patients, IL-2 receptor antagonists should be considered the first-line choice for induction therapy. Newer lymphocyte-depleting agents such as alemtuzumab may be better utilized in minimization regimens involving one or two oral maintenance immunosuppressive agents.

Immunosuppressive strategies to improve outcomes of kidney transplantation

The introduction of several immunosuppressive agents over the past decade has reduced the rate of acute rejection significantly and has improved short-term renal allograft survival. However, their impact on long-term outcomes remains unclear. Current immunosuppressive strategies are focused on improving long-term graft and patient survival along with maintaining allograft function. The approval of the new immunosuppressive agents: rabbit antithymocyte globulin, basiliximab, daclizumab, tacrolimus, mycophenolate, and sirolimus, also has facilitated the development of steroid- and calcineurin inhibitor-sparing regimens in kidney transplantation. We discuss the impact of various immunosuppressive regimens on the outcome measures of kidney transplantation: acute rejection episodes, allograft survival, and renal function.

Efficacy of anti-IL-2 receptor antibodies compared to no induction and to antilymphocyte antibodies in renal transplantation

The relative efficacy of anti-IL-2 receptor antibodies (IL2R Abs) and antilymphocyte antibodies in preventing acute rejection and improving graft survival after renal transplantation is poorly defined. In particular, the benefits of these agents in specific subgroups, such as recipients with different degrees of HLA mismatch, are unknown. Using the SRTR database, we compared IL2R Abs to no induction and to antilymphocyte antibody induction in 48 948 first renal transplant recipients in the United States between 1998 and 2003 with respect to acute rejection and graft failure. IL2R Abs decreased acute rejection at 6 months (OR: 0.81(0.75-0.87)), and reduced graft failure (HR: 0.90(0.84-0.95)), compared to no induction over a follow-up of 1059 days. Compared to IL2R Abs, antilymphocyte Abs were associated with decreased acute rejection (OR: 0.90(0.83-0.99)) at 1 year, but were not associated with improved graft survival (OR: 1.08(1.00-1.18)) over a follow-up of 732 days. The benefit of IL2R Abs in reducing acute rejection increased significantly with greater HLA mismatch (p = 0.007). IL2R Abs remain an important option in the management of renal transplant patients, and may be particularly useful in specific patient subsets.

Basiliximab induction in adult liver transplant recipients with 93% rejection-free patient and graft survival at 24 months

Induction with the use of interleukin-2 receptor monoclonal antibodies may avoid many of the adverse events associated with polyclonal antibodies and significantly impact on rejection-free long-term survival in orthotopic liver transplantation (OLTx). We describe our experience with the use of basiliximab induction therapy in adult OLTx recipients on tacrolimus-based immunosuppression. Forty-six consecutive deceased donor primary OLTx were analyzed. All patients received standard doses of basiliximab, tacrolimus, and steroids. Mycophenolate mofetil was also used as indicated. The mean follow-up period was 17.9 months. Forty-three patients remained rejection-free during follow-up. The actuarial patient and graft survival rate at 2 years was 93%. The rate of histology-proven hepatitis C virus (HCV) recurrence was 24%, with two progressing to severe cholestatic recurrent HCV. None of the study patients developed (cytomegalovirus (CMV) infection or posttransplant lymphoproliferative disease (PTLD). Results were compared to a historical group of 46 OLTx recipients on tacrolimus-based immunosuppression without basiliximab induction. The historical group had a rejection rate of 34% with lower patient and graft survival rates of 71.74% and 69.5%, respectively, at 24 months as well as a higher histological HCV recurrence rate of 77% (17/22), with three patients progressing to graft failure within 2 years. CMV infection and disease developed in 4.5% of the patients. Although PTLD was not observed, three recipients with hepatocellular carcinoma (HCC) developed and died of metastatic HCC. Induction with basiliximab in combination with tacrolimus-based immunosuppressive regimen reduces the incidence of rejection and improves rejection-free survival rate after OLTx without increasing the incidence of CMV, PTLD, or HCV recurrence.

Anti-IL2 Induction in Liver Transplantation with 93% Rejection-Free Patient and Graft Survival at 18 Months

BACKGROUND

Induction with the use of monoclonal antibodies targeting the alpha-chain (CD25) of the high-affinity IL2 receptor may avoid many of the adverse events associated with polyclonal antibodies and significantly impact on rejection-free long-term survival in orthotopic liver transplantation (OLT).

METHODS

Forty-two consecutive deceased donor primary OLT were retrospectively analyzed. All patients received two 20-mg doses of basiliximab (days 0 and 4 after OLT) followed by tacrolimus (0.15 mg/kg/day; 10-15 ng/mL target trough levels), and steroids (methylprednisolone 1 g intraoperatively followed by tapering doses). Mycophenolate mofetil (MMF) 1 g every 12 h was added to the drug combination as needed. The mean follow-up period was 19.3 months (range: 4.8-35.9 months).

RESULTS

The average Model for End-Stage Liver Disease score was 26 (range: 15-40). A total of 39 patients (93%) remained rejection-free during follow-up with an actuarial rejection-free probability of 95% within 3 months. The actuarial patient and graft survival rate (Kaplan-Meier estimated) at 2 years was 93%. Twenty-five patients (60%) were completely off steroids within 3 months post-OLT (mean: 51.1 days, range: 10-90 days). By the 10th month post-OLT, 30/39 (77%) of the patients were completely off steroids. At last follow-up, 30/39 (77%) are on tacrolimus monotherapy with an average dose of 4 mg per day. Six patients (15%) are on double therapy, receiving a combination of tacrolimus and prednisone (two patients) or tacrolimus and MMF (two patients) or tacrolimus and mycophenolic acid (two patients). Only three patients (8%) are receiving triple therapy at last follow-up. Nine patients (21%) experienced at least one episode of infection. Only six (26%) of a total of 23 hepatitis C virus (HCV) recipients developed histology-proven HCV recurrence, with a mean onset of recurrence post-OLT of 3.2 months (range: 1.3-6.3 months). Of these six patients, two are presently undergoing treatment with interferon and ribavirin, one was treated and became HCV RNA negative, one was not treated, one declined treatment, and two died of HCV recurrence. None of the 42 study patients developed cytomegalovirus infection or posttransplant lymphoproliferative disease.

CONCLUSIONS

These preliminary data suggest that basiliximab, given in combination with a tacrolimus-based immunosuppressive regimen, is safe and associated with a low incidence of acute rejection and excellent short-term rejection-free graft and patient survival rate after OLT.

The role of basiliximab induction therapy in organ transplantation

Basiliximab is a chimeric monoclonal antibody that selectively binds to the alpha-subunit (CD25) of IL-2 receptors on the surface of activated T lymphocytes, and is a highly effective prophylaxis agent against rejection in organ transplant recipients. Its pharmacokinetic profile is characterized by a biphasic and slow clearance with long terminal half-life and a volume of distribution within the central compartment and outside the circulatory system. Basiliximab induction demonstrated an excellent safety profile, with no increase in the incidence of malignancy, infections or death. It has also been used effectively in high-risk recipients, steroid-sparing and steroid-minimization protocols, and in post-transplant patients with renal dysfunction who would benefit from delayed introduction of calcineurin inhibitors. Basiliximab induction therapy given at days 0 and 4 after transplantation appears to be safe and cost-effective for immunoprophylaxis in solid organ transplant recipients, specifically in kidney and liver transplantation, when given in conjunction with dual or triple immunosuppressive therapy.

Immunosuppressive preconditioning or induction regimens : evidence to date

The success of solid organ transplantation has been directly related to the development of immunosuppressive drug therapies. Preconditioning or induction therapy was developed to reduce early immunological and nonimmunological renal injury, with the goal of increasing long-term graft survival. However, the routine induction of immunological tolerance to solid organ allograft is currently not achievable because of the morbidity and mortality related to the immunosuppressive regimens themselves. The different therapeutic preconditioning or induction agents and their associated effects on cellular rejection, graft survival outcomes and the need for multiagent post-transplant maintenance therapy are reviewed.