Antibody induction versus corticosteroid induction for liver transplant recipients

Induction immunosuppression in adults undergoing liver transplantation: a network meta-analysis

BACKGROUND

Liver transplantation is considered the definitive treatment for people with liver failure. As part of post-liver transplantation management, immunosuppression (suppressing the host immunity) is given to prevent graft rejections. Immunosuppressive drugs can be classified into those that are used for a short period during the beginning phase of immunosuppression (induction immunosuppression) and those that are used over the entire lifetime of the individual (maintenance immunosuppression), because it is widely believed that graft rejections are more common during the first few months after liver transplantation. Some drugs such as glucocorticosteroids may be used for both induction and maintenance immunosuppression because of their multiple modalities of action. There is considerable uncertainty as to whether induction immunosuppression is necessary and if so, the relative efficacy of different immunosuppressive agents.

OBJECTIVES

To assess the comparative benefits and harms of different induction immunosuppressive regimens in adults undergoing liver transplantation through a network meta-analysis and to generate rankings of the different induction immunosuppressive regimens according to their safety and efficacy.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, Science Citation Index Expanded, World Health Organization International Clinical Trials Registry Platform, and trials registers until July 2019 to identify randomised clinical trials in adults undergoing liver transplantation.

SELECTION CRITERIA

We included only randomised clinical trials (irrespective of language, blinding, or status) in adults undergoing liver transplantation. We excluded randomised clinical trials in which participants had multivisceral transplantation and those who already had graft rejections.

DATA COLLECTION AND ANALYSIS

We performed a network meta-analysis with OpenBUGS using Bayesian methods and calculated the odds ratio (OR), rate ratio, and hazard ratio (HR) with 95% credible intervals (CrIs) based on an available case analysis, according to National Institute of Health and Care Excellence Decision Support Unit guidance.

MAIN RESULTS

We included a total of 25 trials (3271 participants; 8 treatments) in the review. Twenty-three trials (3017 participants) were included in one or more outcomes in the review. The trials that provided the information included people undergoing primary liver transplantation for various indications and excluded those with HIV and those with renal impairment. The follow-up in the trials ranged from three to 76 months, with a median follow-up of 12 months among trials. All except one trial were at high risk of bias, and the overall certainty of evidence was very low. Overall, approximately 7.4% of people who received the standard regimen of glucocorticosteroid induction died and 12.2% developed graft failure. All-cause mortality and graft failure was lower with basiliximab compared with glucocorticosteroid induction: all-cause mortality (HR 0.53, 95% CrI 0.31 to 0.93; network estimate, based on 2 direct comparison trials (131 participants; low-certainty evidence)); and graft failure (HR 0.44, 95% CrI 0.28 to 0.70; direct estimate, based on 1 trial (47 participants; low-certainty evidence)). There was no evidence of differences in all-cause mortality and graft failure between other induction immunosuppressants and glucocorticosteroids in either the direct comparison or the network meta-analysis (very low-certainty evidence). There was also no evidence of differences in serious adverse events (proportion), serious adverse events (number), renal failure, any adverse events (proportion), any adverse events (number), liver retransplantation, graft rejections (any), or graft rejections (requiring treatment) between other induction immunosuppressants and glucocorticosteroids in either the direct comparison or the network meta-analysis (very low-certainty evidence). However, because of the wide CrIs, clinically important differences in these outcomes cannot be ruled out. None of the studies reported health-related quality of life.

FUNDING

the source of funding for 14 trials was drug companies who would benefit from the results of the study; two trials were funded by neutral organisations who have no vested interests in the results of the study; and the source of funding for the remaining nine trials was unclear.

AUTHORS' CONCLUSIONS

Based on low-certainty evidence, basiliximab induction may decrease mortality and graft failure compared to glucocorticosteroids induction in people undergoing liver transplantation. However, there is considerable uncertainty about this finding because this information is based on small trials at high risk of bias. The evidence is uncertain about the effects of different induction immunosuppressants on other clinical outcomes, including graft rejections. Future randomised clinical trials should be adequately powered, employ blinding, avoid post-randomisation dropouts (or perform intention-to-treat analysis), and use clinically important outcomes such as mortality, graft failure, and health-related quality of life.

The use of induction therapy in liver transplantation is highly variable and is associated with posttransplant outcomes

The use of induction immunosuppression in liver transplantation (LT) remains controversial. This was a retrospective cohort study of adult, first-time liver-alone recipients (N = 69 349) at 114 US centers between 2005 and 2018 using data from the United Network for Organ Sharing. The comparative effectiveness of nondepleting and depleting induction (NDI and DI) was assessed. Overall, 27% of recipients received induction with 65.7% of the variance in the receipt of induction being attributed to transplant center alone. NDI and DI were associated with a lower risk of death/graft failure compared to no induction (adjusted hazard ratio 0.90 [95% confidence interval (CI): 0.86-0.95] and 0.91 [95% CI: 0.85-0.97], respectively; P < .001). In nondialysis recipients at the mean transplant estimated glomerular filtration rate (eGFR), NDI was associated with an adjusted gain in eGFR by 6 months of +3.8 mL/min per 1.73 m² and DI of +3.33 mL/min per 1.73 m² compared to no induction (P < .001). Recipients with lower eGFR at LT had greater predicted improvement in eGFR (interaction P < .001). Only NDI was associated with a reduced risk of acute rejection in the first year post-LT (odds ratio 0.87, 95% CI: 0.8-0.94). Significant variability in induction practices exists, with center being a major determinant. The absolute incremental benefits of NDI and DI over no induction were small.

Glucocorticosteroid-free versus glucocorticosteroid-containing immunosuppression for liver transplanted patients

BACKGROUND

Liver transplantation is an established treatment option for end-stage liver failure. Now that newer, more potent immunosuppressants have been developed, glucocorticosteroids may no longer be needed and their removal may prevent adverse effects.

OBJECTIVES

To assess the benefits and harms of glucocorticosteroid avoidance (excluding intra-operative use or treatment of acute rejection) or withdrawal versus glucocorticosteroid-containing immunosuppression following liver transplantation.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, Science Citation Index Expanded and Conference Proceedings Citation Index - Science, Literatura Americano e do Caribe em Ciencias da Saude (LILACS), World Health Organization International Clinical Trials Registry Platform, ClinicalTrials.gov, and The Transplant Library until May 2017.

SELECTION CRITERIA

Randomised clinical trials assessing glucocorticosteroid avoidance or withdrawal versus glucocorticosteroid-containing immunosuppression for liver transplanted people. Our inclusion criteria stated that participants should have received the same co-interventions. We included trials that assessed complete glucocorticosteroid avoidance (excluding intra-operative use or treatment of acute rejection) versus short-term glucocorticosteroids, as well as trials that assessed short-term glucocorticosteroids versus long-term glucocorticosteroids.

DATA COLLECTION AND ANALYSIS

We used RevMan to conduct meta-analyses, calculating risk ratio (RR) for dichotomous variables and mean difference (MD) for continuous variables, both with 95% confidence intervals (CIs). We used a random-effects model and a fixed-effect model and reported both results where a discrepancy existed; otherwise we reported only the results from the fixed-effect model. We assessed the risk of systematic errors using 'Risk of bias' domains. We controlled for random errors by performing Trial Sequential Analysis. We presented our results in a 'Summary of findings' table.

MAIN RESULTS

We included 17 completed randomised clinical trials, but only 16 studies with 1347 participants provided data for the meta-analyses. Ten of the 16 trials assessed complete postoperative glucocorticosteroid avoidance (excluding intra-operative use or treatment of acute rejection) versus short-term glucocorticosteroids (782 participants) and six trials assessed short-term glucocorticosteroids versus long-term glucocorticosteroids (565 participants). One additional study assessed complete post-operative glucocorticosteroid avoidance but could only be incorporated into qualitative analysis of the results due to limited data published in an abstract. All trials were at high risk of bias. Only eight trials reported on the type of donor used. Overall, we found no statistically significant difference for mortality (RR 1.15, 95% CI 0.93 to 1.44; low-quality evidence), graft loss including death (RR 1.15, 95% CI 0.90 to 1.46; low-quality evidence), or infection (RR 0.88, 95% CI 0.73 to 1.05; very low-quality evidence) when glucocorticosteroid avoidance or withdrawal was compared with glucocorticosteroid-containing immunosuppression. Acute rejection and glucocorticosteroid-resistant rejection were statistically significantly more frequent when glucocorticosteroid avoidance or withdrawal was compared with glucocorticosteroid-containing immunosuppression (RR 1.33, 95% CI 1.08 to 1.64; low-quality evidence; and RR 2.14, 95% CI 1.13 to 4.02; very low-quality evidence). Diabetes mellitus and hypertension were statistically significantly less frequent when glucocorticosteroid avoidance or withdrawal was compared with glucocorticosteroid-containing immunosuppression (RR 0.81, 95% CI 0.66 to 0.99; low-quality evidence; and RR 0.76, 95% CI 0.65 to 0.90; low-quality evidence). We performed Trial Sequential Analysis for all outcomes. None of the outcomes crossed the monitoring boundaries or reached the required information size. Hence, we cannot exclude random errors from the results of the conventional meta-analyses.

AUTHORS' CONCLUSIONS

Many of the benefits and harms of glucocorticosteroid avoidance or withdrawal remain uncertain because of the limited number of published randomised clinical trials, limited numbers of participants and outcomes, and high risk of bias in the trials. Glucocorticosteroid avoidance or withdrawal appears to reduce diabetes mellitus and hypertension whilst increasing acute rejection, glucocorticosteroid-resistant rejection, and renal impairment. We could identify no other benefits or harms of glucocorticosteroid avoidance or withdrawal. Glucocorticosteroid avoidance or withdrawal may be of benefit in selected patients, especially those at low risk of rejection and high risk of hypertension or diabetes mellitus. The optimal duration of glucocorticosteroid administration remains unclear. More randomised clinical trials assessing glucocorticosteroid avoidance or withdrawal are needed. These should be large, high-quality trials that minimise the risk of random and systematic error.

Liver Transplantation: the Role of Metabolic Syndrome

OPINION STATEMENT

The long-term survival in liver transplant recipients (LTRs) is currently at an historical high level stemming from improvement in perioperative care, infection control, and immunosuppression medications. However, compared to the general population, LTRs have decreased survival. Metabolic diseases like hypertension, dyslipidemia, type 2 diabetes, and obesity are key determinants of long-term mortality in LTRs. The incidence and prevalence of these metabolic comorbidities is considerably higher in LTRs and likely results from a combination of factors including exposure to chronic immunosuppression, weight gain, and recurrence of chronic liver disease after liver transplantation (LT). Although there is currently little guidance in managing these metabolic conditions post-LT, recommendations are often extrapolated from non-transplant cohorts. In the current review, we explore the relationship between metabolic syndrome and its comorbidities in LTRs.

The Impact of Therapeutic Antibodies on the Management of Digestive Diseases: History, Current Practice, and Future Directions

The development of therapeutic antibodies represents a revolutionary change in medical therapy for digestive diseases. Beginning with the initial studies that confirmed the pathogenicity of cytokines in inflammatory bowel disease, the development and application of therapeutic antibodies brought challenges and insights into their potential and optimal use. Infliximab was the first biological drug approved for use in Crohn's disease and ulcerative colitis. The lessons learned from infliximab include the importance of immunogenicity and the influence of pharmacokinetics on disease response and outcomes. Building on this foundation, other therapeutic antibodies achieved approval for inflammatory bowel disease and many more are in development for several digestive diseases. In this review, we reflect on the history of therapeutic antibodies and discuss current practice and future directions for the field.

Maintenance immunosuppression for adults undergoing liver transplantation: a network meta-analysis

BACKGROUND

As part of liver transplantation, immunosuppression (suppressing the host immunity) is given to prevent graft rejections resulting from the immune response of the body against transplanted organ or tissues from a different person whose tissue antigens are not compatible with those of the recipient. The optimal maintenance immunosuppressive regimen after liver transplantation remains uncertain.

OBJECTIVES

To assess the comparative benefits and harms of different maintenance immunosuppressive regimens in adults undergoing liver transplantation through a network meta-analysis and to generate rankings of the different immunosuppressive regimens according to their safety and efficacy.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, Science Citation Index Expanded, World Health Organization International Clinical Trials Registry Platform, and trials registers until October 2016 to identify randomised clinical trials on immunosuppression for liver transplantation.

SELECTION CRITERIA

We included only randomised clinical trials (irrespective of language, blinding, or publication status) in adult participants undergoing liver transplantation (or liver retransplantation) for any reason. We excluded trials in which participants had undergone multivisceral transplantation or participants with established graft rejections. We considered any of the various maintenance immunosuppressive regimens compared with each other.

DATA COLLECTION AND ANALYSIS

We performed a network meta-analysis with OpenBUGS using Bayesian methods and calculated the odds ratio, rate ratio, and hazard ratio (HR) with 95% credible intervals (CrI) based on an available-case analysis, according to National Institute of Health and Care Excellence Decision Support Unit guidance.

MAIN RESULTS

We included a total of 26 trials (3842 participants) in the review, and 23 trials (3693 participants) were included in one or more outcomes in the review. The vast majority of the participants underwent primary liver transplantation. All of the trials were at high risk of bias, and all of the evidence was of low or very low quality. In addition, because of sparse data involving trials at high risk of bias, it is not possible to entirely rely on the results of the network meta-analysis. The trials included mainly participants undergoing primary liver transplantation of varied aetiologies. The follow-up in the trials ranged from 3 to 144 months. The most common maintenance immunosuppression used as a control was tacrolimus. There was no evidence of difference in mortality (21 trials; 3492 participants) or graft loss (15 trials; 2961 participants) at maximal follow-up between the different maintenance immunosuppressive regimens based on the network meta-analysis. In the direct comparison, based on a single trial including 222 participants, tacrolimus plus sirolimus had increased mortality (HR 2.76, 95% CrI 1.30 to 6.69) and graft loss (HR 2.34, 95% CrI 1.28 to 4.61) at maximal follow-up compared with tacrolimus. There was no evidence of differences in the proportion of people with serious adverse events (1 trial; 719 participants), proportion of people with any adverse events (2 trials; 940 participants), renal impairment (8 trials; 2233 participants), chronic kidney disease (1 trial; 100 participants), graft rejections (any) (16 trials; 2726 participants), and graft rejections requiring treatment (5 trials; 1025 participants) between the different immunosuppressive regimens. The network meta-analysis showed that the number of adverse events was lower with cyclosporine A than with many other immunosuppressive regimens (12 trials; 1748 participants), and the risk of retransplantation (13 trials; 1994 participants) was higher with cyclosporine A than with tacrolimus (HR 3.08, 95% CrI 1.13 to 9.90). None of the trials reported number of serious adverse events, health-related quality of life, or costs.

FUNDING

14 trials were funded by pharmaceutical companies who would benefit from the results of the trial; two trials were funded by parties who had no vested interest in the results of the trial; and 10 trials did not report the source of funding.

AUTHORS' CONCLUSIONS

Based on low-quality evidence from a single small trial from direct comparison, tacrolimus plus sirolimus increases mortality and graft loss at maximal follow-up compared with tacrolimus. Based on very low-quality evidence from network meta-analysis, we found no evidence of difference between different immunosuppressive regimens. We found very low-quality evidence from network meta-analysis and low-quality evidence from direct comparison that cyclosporine A causes more retransplantation compared with tacrolimus. Future randomised clinical trials should be adequately powered; performed in people who are generally seen in the clinic rather than in highly selected participants; employ blinding; avoid postrandomisation dropouts or planned cross-overs; and use clinically important outcomes such as mortality, graft loss, renal impairment, chronic kidney disease, and retransplantation. Such trials should use tacrolimus as one of the control groups. Moreover, such trials ought to be designed in such a way as to ensure low risk of bias and low risks of random errors.

Glucocorticosteroid-free versus glucocorticosteroid-containing immunosuppression for liver transplanted patients

BACKGROUND

Liver transplantation is an established treatment option for end-stage liver failure. Now that newer, more potent immunosuppressants have been developed, glucocorticosteroids may no longer be needed and their removal may prevent adverse effects.

OBJECTIVES

To assess the benefits and harms of glucocorticosteroid avoidance (excluding intra-operative use) or withdrawal versus glucocorticosteroid-containing immunosuppression following liver transplantation.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Science Citation Index Expanded and Social Sciences Citation Index, The Transplant Library, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) until September 2014.

SELECTION CRITERIA

Randomised clinical trials assessing glucocorticosteroid avoidance or withdrawal versus glucocorticosteroid-containing immunosuppression for liver-transplanted people. Our inclusion criteria stated that participants should have received the same co-interventions. We included trials that assessed complete glucocorticosteroid avoidance (excluding the perioperative period and excluding the occurrence of acute rejection) versus short-term glucocorticosteroids, as well as trials that assessed short-term glucocorticosteroids versus long-term glucocorticosteroids.

DATA COLLECTION AND ANALYSIS

We used RevMan to conduct meta-analyses, calculating risk ratio (RR) for dichotomous variables and mean difference (MD) for continuous variables, both with 95% confidence intervals (CIs). We used a random-effects model and a fixed-effect model and reported both results where a discrepancy existed. We assessed the risk of systematic errors using risk of bias domains. We controlled for random errors by performing Trial Sequential Analysis. We presented our results in a 'Summary of findings' table.

MAIN RESULTS

We included 16 completed randomised clinical trials with a total of 1347 participants. We found 10 trials that assessed complete postoperative glucocorticosteroid avoidance (excluding intra-operative use and treatment of rejection) versus short-term glucocorticosteroids (782 participants) and six trials that assessed short-term glucocorticosteroids versus long-term glucocorticosteroids (565 participants). We found one ongoing trial assessing complete postoperative glucocorticosteroid avoidance versus short-term glucocorticosteroids, which is expected to enrol 300 participants. All trials were at high risk of bias. Overall, we found no statistically significant difference for mortality (RR 1.15, 95% CI 0.93 to 1.44; low-quality evidence), graft loss including death (RR 1.16, 95% CI 0.91 to 1.48; low-quality evidence), or infection (RR 0.88, 95% CI 0.73 to 1.05; low-quality evidence) when glucocorticosteroid avoidance or withdrawal was compared with glucocorticosteroid-containing immunosuppression. Acute rejection and glucocorticosteroid-resistant rejection were statistically significantly more frequent when glucocorticosteroid avoidance or withdrawal was compared with glucocorticosteroid-containing immunosuppression (RR 1.33, 95% CI 1.08 to 1.64; moderate-quality evidence; and RR 2.14, 95% CI 1.13 to 4.02; very low-quality evidence). Diabetes mellitus and hypertension were statistically significantly less frequent when glucocorticosteroid avoidance or withdrawal was compared with glucocorticosteroid-containing immunosuppression (RR 0.81, 95% CI 0.66 to 0.99; low-quality evidence; and RR 0.76, 95% CI 0.65 to 0.90; low-quality evidence). We performed Trial Sequential Analysis for all outcomes. None of the outcomes crossed the monitoring boundaries or reached the required information size. Hence, we cannot exclude random errors from the results of the conventional meta-analyses.

AUTHORS' CONCLUSIONS

Many of the benefits and harms of glucocorticosteroid avoidance or withdrawal remain uncertain because of the limited number of published randomised clinical trials, limited numbers of participants and outcomes, and high risk of bias in the trials. Glucocorticosteroid avoidance or withdrawal appears to reduce diabetes mellitus and hypertension whilst increasing acute rejection, glucocorticosteroid-resistant rejection, and renal impairment. We could identify no other benefits or harms of glucocorticosteroid avoidance or withdrawal. Glucocorticosteroid avoidance or withdrawal may be of benefit in selected patients, especially those at low risk of rejection and high risk of hypertension or diabetes mellitus. The optimal duration of glucocorticosteroid administration remains unclear. More randomised clinical trials assessing glucocorticosteroid avoidance or withdrawal are needed. These should be large, high-quality trials that minimise the risk of random and systematic error.

Review on immunosuppression in liver transplantation

The optimal level of immunosuppression in solid organ transplantation, in particular for the liver, is a delicate balance between the benefit of preventing rejection and the adverse side effects of immunosuppression. There is uncertainty about when this level is achieved in any individual recipient. Immunosuppression regimens vary between individual centers and changes with time as new agents and data are available. Presently concerns about the adverse side effects of calcineurin inhibitor, the main class of immunosuppressive agents used in liver transplantation (LT), has led to consideration of the use of antibody induction therapies for patients at higher risk of developing adverse side effects. The longevity of the transplanted organ is potentially improved by better management of rejection episodes and special consideration for tailoring of immunosuppression to the individual with viral hepatitis C, hepatocellular carcinoma or pregnancy. This review provides an overview of the current strategies for post LT immunosuppression and discusses modifications to consider for special patient populations.

Antibody induction versus placebo, no induction, or another type of antibody induction for liver transplant recipients

BACKGROUND

Liver transplantation is an established treatment option for end-stage liver failure. To date, no consensus has been reached on the use of immunosuppressive T-cell antibody induction for preventing rejection after liver transplantation.

OBJECTIVES

To assess the benefits and harms of immunosuppressive T-cell specific antibody induction compared with placebo, no induction, or another type of T-cell specific antibody induction for prevention of acute rejection in liver transplant recipients.

SEARCH METHODS

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Science Citation Index Expanded, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) until September 2013.

SELECTION CRITERIA

Randomised clinical trials assessing immunosuppression with T-cell specific antibody induction compared with placebo, no induction, or another type of antibody induction in liver transplant recipients. Our inclusion criteria stated that participants within each included trial should have received the same maintenance immunosuppressive therapy. We planned to include trials with all of the different types of T-cell specific antibodies that are or have been used for induction (ie., polyclonal antibodies (rabbit of horse antithymocyte globulin (ATG), or antilymphocyte globulin (ALG)), monoclonal antibodies (muromonab-CD3, anti-CD2, or alemtuzumab), and interleukin-2 receptor antagonists (daclizumab, basiliximab, BT563, or Lo-Tact-1)).

DATA COLLECTION AND ANALYSIS

We used RevMan analysis for statistical analysis of dichotomous data with risk ratio (RR) and of continuous data with mean difference (MD), both with 95% confidence intervals (CIs). We assessed the risk of systematic errors (bias) using bias risk domains with definitions. We used trial sequential analysis to control for random errors (play of chance). We presented outcome results in a summary of findings table.

MAIN RESULTS

We included 19 randomised clinical trials with a total of 2067 liver transplant recipients. All 19 trials were with high risk of bias. Of the 19 trials, 16 trials were two-arm trials, and three trials were three-arm trials. Hence, we found 25 trial comparisons with antibody induction agents: interleukin-2 receptor antagonist (IL-2 RA) versus no induction (10 trials with 1454 participants); monoclonal antibody versus no induction (five trials with 398 participants); polyclonal antibody versus no induction (three trials with 145 participants); IL-2 RA versus monoclonal antibody (one trial with 87 participants); and IL-2 RA versus polyclonal antibody (two trials with 112 participants). Thus, we were able to compare T-cell specific antibody induction versus no induction (17 trials with a total of 1955 participants). Overall, no difference in mortality (RR 0.91; 95% CI 0.64 to 1.28; low-quality of evidence), graft loss including death (RR 0.92; 95% CI 0.71 to 1.19; low-quality of evidence), and adverse events ((RR 0.97; 95% CI 0.93 to 1.02; low-quality evidence) outcomes was observed between any kind of T-cell specific antibody induction compared with no induction when the T-cell specific antibody induction agents were analysed together or separately. Acute rejection seemed to be reduced when any kind of T-cell specific antibody induction was compared with no induction (RR 0.85, 95% CI 0.75 to 0.96; moderate-quality evidence), and when trial sequential analysis was applied, the trial sequential monitoring boundary for benefit was crossed before the required information size was obtained. Furthermore, serum creatinine was statistically significantly higher when T-cell specific antibody induction was compared with no induction (MD 3.77 μmol/L, 95% CI 0.33 to 7.21; low-quality evidence), as well as when polyclonal T-cell specific antibody induction was compared with no induction, but this small difference was not clinically significant. We found no statistically significant differences for any of the remaining predefined outcomes - infection, cytomegalovirus infection, hepatitis C recurrence, malignancy, post-transplant lymphoproliferative disease, renal failure requiring dialysis, hyperlipidaemia, diabetes mellitus, and hypertension - when the T-cell specific antibody induction agents were analysed together or separately. Limited data were available for meta-analysis on drug-specific adverse events such as haematological adverse events for antithymocyte globulin. No data were found on quality of life.When T-cell specific antibody induction agents were compared with another type of antibody induction, no statistically significant differences were found for mortality, graft loss, and acute rejection for the separate analyses. When interleukin-2 receptor antagonists were compared with polyclonal T-cell specific antibody induction, drug-related adverse events were less common among participants treated with interleukin-2 receptor antagonists (RR 0.23, 95% CI 0.09 to 0.63; low-quality evidence), but this was caused by the results from one trial, and trial sequential analysis could not exclude random errors. We found no statistically significant differences for any of the remaining predefined outcomes: infection, cytomegalovirus infection, hepatitis C recurrence, malignancy, post-transplant lymphoproliferative disease, renal failure requiring dialysis, hyperlipidaemia, diabetes mellitus, and hypertension. No data were found on quality of life.

AUTHORS' CONCLUSIONS

The effects of T-cell antibody induction remain uncertain because of the high risk of bias of the randomised clinical trials, the small number of randomised clinical trials reported, and the limited numbers of participants and outcomes in the trials. T-cell specific antibody induction seems to reduce acute rejection when compared with no induction. No other clear benefits or harms were associated with the use of any kind of T-cell specific antibody induction compared with no induction, or when compared with another type of T-cell specific antibody. Hence, more randomised clinical trials are needed to assess the benefits and harms of T-cell specific antibody induction compared with placebo, and compared with another type of antibody, for prevention of rejection in liver transplant recipients. Such trials ought to be conducted with low risks of systematic error (bias) and low risk of random error (play of chance).

Antibody induction therapy for lung transplant recipients

BACKGROUND

Lung transplantation has become a valuable and well-accepted treatment option for most end-stage lung diseases. Lung transplant recipients are at risk of transplanted organ rejection, and life-long immunosuppression is necessary. Clear evidence is essential to identify an optimal, safe and effective immunosuppressive treatment strategy for lung transplant recipients. Consensus has not yet been achieved concerning use of immunosuppressive antibodies against T-cells for induction following lung transplantation.

OBJECTIVES

We aimed to assess the benefits and harms of immunosuppressive T-cell antibody induction with ATG, ALG, IL-2RA, alemtuzumab, or muromonab-CD3 for lung transplant recipients.

SEARCH METHODS

We searched the Cochrane Renal Group's Specialised Register to 4 March 2013 through contact with the Trials Search Co-ordinator using search terms relevant to this review. Studies contained in the Specialised Register are identified through search strategies specifically designed for CENTRAL, MEDLINE and EMBASE.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) that compared immunosuppressive monoclonal and polyclonal T-cell antibody induction for lung transplant recipients. An inclusion criterion was that all participants must have received the same maintenance immunosuppressive therapy within each study.

DATA COLLECTION AND ANALYSIS

Three authors extracted data. We derived risk ratios (RR) for dichotomous data and mean differences (MD) for continuous data with 95% confidence intervals (CI). Methodological risk of bias was assessed using the Cochrane risk of bias tool and trial sequential analyses were undertaken to assess the risk of random errors (play of chance).

MAIN RESULTS

Our review included six RCTs (representing a total of 278 adult lung transplant recipients) that assessed the use of T-cell antibody induction. Evaluation of the included studies found all to be at high risk of bias.We conducted comparisons of polyclonal or monoclonal T-cell antibody induction versus no induction (3 studies, 140 participants); polyclonal T-cell antibody versus no induction (3 studies, 125 participants); interleukin-2 receptor antagonists (IL-2RA) versus no induction (1 study, 25 participants); polyclonal T-cell antibody versus muromonab-CD3 (1 study, 64 participants); and polyclonal T-cell antibody versus IL-2RA (3 studies, 100 participants). Overall we found no significant differences among interventions in terms of mortality, acute rejection, adverse effects, infection, pneumonia, cytomegalovirus infection, bronchiolitis obliterans syndrome, post-transplantation lymphoproliferative disease, or cancer.We found a significant outcome difference in one study that compared antithymocyte globulin versus muromonab-CD3 relating to adverse events (25/34 (74%) versus 12/30 (40%); RR 1.84, 95% CI 1.13 to 2.98). This suggested that antithymocyte globulin increased occurrence of adverse events. However, trial sequential analysis found that the required information size had not been reached, and the cumulative Z-curve did not cross the trial sequential alpha-spending monitoring boundaries.None of the studies reported quality of life or kidney injury. Trial sequential analyses indicated that none of the meta-analyses achieved required information sizes and the cumulative Z-curves did not cross the trial sequential alpha-spending monitoring boundaries, nor reached the area of futility.

AUTHORS' CONCLUSIONS

No clear benefits or harms associated with the use of T-cell antibody induction compared with no induction, or when different types of T-cell antibodies were compared were identified in this review. Few studies were identified that investigated use of antibodies against T-cells for induction after lung transplantation, and numbers of participants and outcomes were also limited. Assessment of the included studies found that all were at high risk of methodological bias.Further RCTs are needed to perform robust assessment of the benefits and harms of T-cell antibody induction for lung transplant recipients. Future studies should be designed and conducted according to methodologies to reduce risks of systematic error (bias) and random error (play of chance).