Steroid-free Liver Transplantation Using Rabbit Antithymocyte Globulin Induction in 500 Consecutive Patients

Basics and Art of Immunosuppression in Liver Transplantation

Liver transplantation is one of the most challenging areas in the medical field. Despite that, it has already been established as a standard treatment option, especially in decompensated cirrhosis and selected cases of hepatocellular carcinoma and acute liver failure. Complications due to graft rejection, including mortality and morbidity, have greatly improved over time due to better immunosuppressive agents and management protocols. Currently, immunosuppression in liver transplant patients makes use of the best possible combinations of effective agents to achieve optimal immunosuppression for long-term graft survival. Induction agents are no longer used routinely, and the aim is to provide minimal immunosuppression in the maintenance phase. Currently available immunosuppressive agents are mainly classified as biological and pharmacological agents. Though the protocols may vary among the centers and over time, the basics of effective use usually remain similar. Most protocols use the combination of multiple agents with different mechanisms of action to reduce the dose and minimize the side effects. Along with the improvement in operative and perioperative techniques, this art of immunosuppression has contributed to the recent progress made in the outcomes of liver transplants. In this review, we will discuss the various types of immunosuppressive agents currently in use, the different protocols of immunosuppression used, and the art of optimal use for achieving maximum immunosuppression without increasing toxicity. We will also discuss the practical aspects of various immunosuppression regimens, including drug monitoring, and briefly discuss the concepts of immunosuppression minimization and withdrawal.

Current Use of Immunosuppression in Liver Transplantation

Since the first successful liver transplant in 1967, immunosuppression has allowed liver transplantation to become the standard treatment of end-stage liver disease. Over the decades, the rates of rejection have decreased, and patient survival outcomes have significantly improved in large part due to the introduction and advancements of immunosuppression medications. However, the adverse effects associated with long-term immunosuppression have created new challenges facing liver transplantation and added significantly to posttransplantation morbidity. This review presents the data and rationale for immunosuppression approaches, addresses the main controversies related to immunosuppression in liver transplantation, and explores some of the newer advancements in immunosuppressive drug therapy.

A report of a prospective randomized trial of extended-release tacrolimus versus immediate release tacrolimus after liver transplantation with anti-thymocyte induction in a steroid free protocol

PURPOSE

Our study hypothesis was that once daily dosing of extended-release tacrolimus (XRT) would be a safe and effective immunosuppression (IS) with the potential to decrease adverse events (AEs) associated with immediate release tacrolimus (IRT) after liver transplantation (LT).

METHODS

All patients receiving LT at our center received rabbit anti-thymocyte globulin (RATG) induction therapy. Eligible patients were randomized in a 1:1 fashion to receive either XRT or IRT. Antimicrobial prophylaxis was the same between arms, and both groups received an antimetabolite for the first 6 months following LT. Patients were then followed at pre-determined study intervals for the following year after LT. We administered the RAND-36SF survey to assess patient's health-related quality of life at pre-determined intervals. All analysis was performed with an intention to treat basis.

RESULTS

We screened 194 consecutive patients and enrolled 110. Our control and study arms were well matched. Transplant characteristics were similar between groups. At all timepoints, both arms had similar serum creatinine and estimated glomerular filtration rate (eGFR), calculated by MDRD6 equation, with post-transplant GFRs between 60 and 70 mL/min/1.73 m2 . Tacrolimus trough levels were similar between arms. The XRT arm had fewer AEs (166) and fewer serious AEs (70) compared to IRT (201 and 99, respectively). AEs most commonly were renal, infectious, or gastrointestinal in nature. While not statistically significant, XRT was held temporarily (25 vs. 35 cases) or discontinued (3 vs. 11 cases) less frequently than IRT and had fewer instances of rejection (7 vs. 12 cases).

CONCLUSION

This analysis showed that XRT is safe and effective as de novo maintenance IS in a steroid-free protocol with RATG.

Immunosuppression in liver and intestinal transplantation

Immunosuppression handling plays a key role in the early and long-term results of transplantation. The development of multiple immunosuppressive drugs led to numerous clincial trials searching to reach the ideal regimen. Due to heterogeneity of the studied patient cohorts and flaws in many, even randomized controlled, study designs, the answer still stands out. Nowadays triple-drug immunosuppression containing a calcineurin inhibitor (preferentially tacrolimus), an antimetabolite (using mycophenolate moffettil or Azathioprine) and short-term steroids with or without induction therapy (using anti-IL2 receptor blocker or anti-lymphocytic serum) is the preferred option in both liver and intestinal transplantation. This chapter aims, based on a critical review of the definitions of rejection, corticoresistant rejection and standard immunosuppression to give some reflections on how to reach an optimal immunosuppressive status and to conduct trials allowing to draw solid conclusions. Endpoints of future trials should not anymore focus on biopsy proven, acute and chronic, rejection but also on graft and patient survival. Correlation between early- and long-term biologic, immunologic and histopathologic findings will be fundamental to reach in much more patients the status of operational tolerance.

Medical care of liver transplant patients

INTRODUCTION

Liver transplantation is a life-changing event for patients and survival following transplantation has improved significantly since the first transplantation in 1967. Following liver transplantation, patients face a unique set of healthcare management decisions including transplantation-specific complications, recurrence of primary liver disease, as well as metabolic and malignancy concerns related to immunosuppression. As more patients with liver disease receive transplantation and live longer, understanding and managing these patients will require not only transplant specialist but also local subspecialist and primary care physicians.

AREAS COVERED

This review covers common issues related to the management of patients following liver transplantation including immunosuppression, liver allograft dysfunction, metabolic complications, as well as routine health maintenance such as immunizations and cancer screening.

EXPERT OPINION

Optimizing medical care for patients following liver transplant will benefit from ensuring all providers, not just transplant specialist, have a basic understanding of the common issues encountered in the post-transplant patient. This review provides an overview of common healthcare concerns and management options for patients following liver transplantation.

Immunosuppression in Donation After Circulatory Death Liver Transplantation: Can Induction Modify Graft Survival?

Recipients of donation after circulatory death (DCD) LTs historically have an increased risk of graft failure. Antibody induction (AI) with antithymocyte globulin (ATG) or anti-interleukin 2 receptor (anti-IL2R) immunotherapy may decrease the incidence of graft failure by mitigating ischemia/reperfusion injury. A retrospective review of the United Network for Organ Sharing (UNOS) database for LTs between 2002 and 2015 was conducted to determine whether ATG or anti-IL2R AI was associated with graft survival in DCD. A secondary endpoint was postoperative renal function as measured by estimated glomerular filtration rate at 6 and 12 months. Among DCD recipients, ATG (hazard ratio [HR] = 0.71; P = 0.03), but not anti-IL2R (HR = 0.82; P = 0.10), was associated with a decrease in graft failure at 3 years when compared with recipients without AI. ATG (HR = 0.90; P = 0.02) and anti-IL2R (HR = 0.94; P = 0.03) were associated with a decreased risk of graft failure in donation after brain death (DBD) liver recipients at 3 years compared with no AI. When induction regimens were compared between DCD and DBD, only ATG (HR = 1.19; P = 0.19), and not anti-IL2R (HR = 1.49; P < 0.01) or no AI (HR = 1.77; P < 0.01), was associated with similar survival between DCD and DBD. In conclusion, AI therapy with ATG was associated with improved longterm liver allograft survival in DCD compared with no AI. ATG was associated with equivalent graft survival between DCD and DBD, suggesting a beneficial role of immune cell depletion in DCD outcomes.

Longitudinal Renal Function in Liver Transplant Recipients With Acute-on-Chronic Liver Failure

To analyze the impact of acute-on-chronic liver failure (ACLF) immediately before liver transplantation (LT) on short-term kidney function.

Association between longer hospitalization and development of de novo donor specific antibodies in simultaneous liver-kidney transplant recipients

Background: De novo Donor Specific Antibodies (DSA) are considered as a risk factor for the kidney allograft outcomes in recipients after simultaneous liver-kidney transplantation (SLKT). We hypothesized that length of hospital stay (LOS) might be associated with de novo DSA development of due to the increased likelihood of receiving blood transfusions with reduced immunosuppressive regimens.Methods: This study is a single-center, retrospective cohort study consisting of 85 recipients who underwent SLKT from 2009 to 2018 in our hospital. We divided the patients into two groups according to LOS [long hospital stay (L) group (LOS >14 days) and short hospital stay (S) group (LOS ≤14 days)]. Propensity score (PS) has been created using logistic regression to predict LOS greater than median of 14 days. The association between the presence of de novo DSA and LOS was assessed by logistic regression models adjusted for PS.Results: The mean age at transplantation of the entire cohort was 55.5 ± 10.1 years. Sixty percent of the recipients were male and Caucasian. Median LOS in (L) group was three-fold longer than (S) group [L: median 30 days (IQR: 21-52), S: median 8.5 days (IQR: 7-11)]. Eight patients developed de novo DSA after SLKT (9.4%), all of them were in (L) group. Longer LOS was significantly associated with higher risk of development of de novo DSA in unadjusted (OR_{+ each 5 days}: 1.09, 95% CI:1.02-1.16) and PS adjusted (OR_{+ each 5 days}: 1.11, 95% CI:1.02-1.21) analysis.Conclusion: Longer hospitalization is significantly associated with the development of de novo DSA in SLKT.

Low Total Dose of Anti-Human T-Lymphocyte Globulin (ATG) Guarantees a Good Glomerular Filtration Rate after Liver Transplant in Recipients with Pretransplant Renal Dysfunction

We aimed to evaluate the safety and efficacy of low doses of anti-T-lymphocyte globulin (ATG)-based immunosuppression in preserving renal function and preventing liver rejection in liver transplant (LT) recipients with pretransplant renal dysfunction. We designed a prospective single-center cohort study analyzing patients with pre-LT renal dysfunction defined as eGFR<60 mL/min/1.73m2, who underwent induction therapy with ATG (ATG group, n=20). This group was compared with a similar retrospective cohort treated with basiliximab (BAS group, n=20). An economic analysis between both induction therapies was also undertaken. In the ATG group, 45% and 50% of patients had recovered their renal function without acute cellular rejection (ACR) episodes at day 7 and 1 month after LT, respectively, versus 40% and 55% of patients in the BAS group (p=1). Renal function improved in both groups over time and no differences between groups were observed regarding one-year eGRF and one-year probability of ACR. Cost per patient of the ATG course was 403€ (r: 126-756) versus 2,524€ of the basiliximab course (p=0.001). In conclusion, induction with low dose of ATG or basiliximab in patients with pretransplant renal dysfunction is a good strategy for preserving posttransplant renal function; however the use of low-dose ATG resulted in a substantial reduction in drug costs. This trail is registered with ClinicalTrials.gov number: NCT01453218.

Achieving Sustained Virological Response in Liver Transplant Recipients With Hepatitis C Decreases Risk of Decline in Renal Function

The effect of antiviral therapy (AVT) on kidney function in liver transplantation (LT) recipients has not been well described despite known association of hepatitis C virus (HCV) infection with chronic kidney disease (CKD). We compared the incidence of CKD and end-stage renal disease (ESRD) in 204 LT recipients with HCV based on treatment response to AVT. The mean estimated glomerular filtration rate (eGFR) at baseline (3 months after LT) was similar in the sustained virological response (SVR; n = 145) and non-SVR group (n = 59; 69 ± 21 versus 65 ± 33 mL/minute/1.73 m² ; P = 0.27). In the unadjusted Cox proportional regression analysis, the presence of SVR was associated with an 88% lower risk of CKD (hazard ratio, 0.12; 95% confidence interval [CI], 0.05-0.31) and 86% lower risk of ESRD (odds ratio, 0.14; 95% CI, 0.05-0.35). Similar results were found after adjusting for propensity score and time-dependent Cox regression analyses. The estimated slopes of eGFR based on a 2-stage mixed model of eGFR were calculated. Patients with SVR had a less steep slope in eGFR (-0.60 mL/minute/1.73 m² /year; 95% CI, -1.50 to 0.30; P = 0.190) than recipients without SVR (-2.53 mL/minute/1.73 m² /year; 95% CI, -3.99 to -1.07; P = 0.001), and the differences in the slopes were statistically significant (P = 0.026). In conclusion, in LT recipients with chronic HCV infection, achieving SVR significantly lowers the risk of decline in renal function and progression to ESRD independent of the AVT therapy used.

Center-driven and Clinically Driven Variation in US Liver Transplant Maintenance Immunosuppression Therapy: A National Practice Patterns Analysis

Supplemental digital content is available in the text.

Background

Variation in the use of immunosuppression regimens after liver transplant has not been well described.

Methods

Immunosuppression regimens used after liver transplant were identified in a novel database integrating national transplant registry and pharmacy fill records for 24 238 recipients (2006-2014). Bilevel hierarchical models were developed to quantify the effects of transplant program, recipient, and donor characteristics on regimen choice.

Results

In the first 6 months after transplant, triple immunosuppression (tacrolimus, antimetabolite, corticosteroids) was the most common regimen (42.9%). By months 7 to 12, immunosuppression regimens were more commonly antimetabolite sparing (33.7%) or steroid sparing (26.9%), followed by triple (14.4%), mammalian target of rapamycin inhibitor (mTORi)-based (12.1%), or cyclosporine-based (9.2%). Based on intraclass correlation analysis, clinical characteristics explained less than 10% of the variation in immunosuppression choice, whereas program preference/practice explained 23% of steroid sparing, 26% of antimetabolite sparing, 28% of mTORi, and 21% of cyclosporine-based regimen use. Although case factors were not dominant practice drivers, triple immunosuppression in months 7 to 12 was more common among retransplant recipients and those with prior acute rejection. Hepatocellular carcinoma as cause of liver failure (adjusted odds ratio [aOR], 2.15; P<0.001), cancer within 6 months (aOR, 6.07; P<0.001), and 6-month estimated glomerular filtration rate less than 30 mL/min per 1.3 m² (aOR, 1.98; P<0.001) were associated with mTORi use compared with triple immunosuppression in months 7 to 12, whereas acute rejection predicted lower use (aOR, 0.72; P=0.003).

Conclusions

Liver transplant immunosuppression is dominantly driven by program preference, but case factors also affect regimen choice. This variation frames a natural experiment for future evaluations of comparative efficacy.

Outcomes of Liver Transplant Recipients With Autoimmune Liver Disease Using Long-Term Dual Immunosuppression Regimen Without Corticosteroid

Background

Liver transplant (LT) recipients with autoimmune liver disease (primary sclerosing cholangitis, primary biliary cholangitis, autoimmune hepatitis) are at increased risk of developing acute cellular rejection (ACR), and in many cases graft failure due to recurrent disease. We describe our experience with dual immunosuppression without steroid maintenance and analyze its effect on disease recurrence; ACR; patient and graft survivals; and complications, such as sepsis and de novo malignancy.

Methods

We included 74 consecutive LT recipients (April 2006 to April 2013) with autoimmune liver disease (primary sclerosing cholangitis, 20; primary biliary cholangitis, 23; autoimmune hepatitis, 31) from a single transplant center. Immunosuppression protocol included rabbit antithymocyte globulin for induction and mycophenolate mofetil with tacrolimus or sirolimus/everolimus indefinitely for maintenance.

Results

Overall 1-, 3-, 5-, and 7-year patient survival was 95.9%, 90.4%, 82,2% and 74.9%, re–graft-free survival was 93.2%, 86.3%, 79.9%, and 72.8%, respectively (median follow-up, 5.5 years). In a multivariate Cox regression analysis, sepsis during post-LT period (P = 0.040; hazard ratio [HR], 2.52; 95% confidence interval [CI], 1.04-6.11), steroid use for ACR (P = 0.037; HR, 2.60; 95% CI, 1.06-6.34), and younger age (<40 years) at LT (P = 0.038; HR, 2.53; 95% CI, 1.05-6.10) predicted graft survival, whereas steroid use for ACR was the only variable that was predictive of overall patient survival (P = 0.004; HR, 4.10; 95% CI, 1.59-10.52). Overall, 34 biopsy-proven ACR was noted in 22 LT recipients (30%), 13 (17.5%) had disease recurrence, and 34 episodes of sepsis occurred in 19 patients.

Conclusions

Dual immunosuppression protocol in LT recipients with autoimmune liver disease without corticosteroid maintenance had acceptable rates of survival and ACR without predisposing patients to the adverse effects of long-term steroid therapy.

Antithymocyte Globulin Induction Therapy in Liver Transplant: Old Drug, New Uses

OBJECTIVE

To review the use of rabbit antithymocyte globulin (rATG) induction therapy in liver transplant recipients.

DATA SOURCES

A MEDLINE literature search (inception to March 2016) was conducted using the search terms rabbit antithymocyte globulin, liver transplantation, and induction References from extracted sources were further searched for any relevant, missed data sources.

STUDY SELECTION AND DATA EXTRACTION

All English-language randomized and observational studies were included.

DATA SYNTHESIS

A total of 9 studies were included in this review evaluating rATG's use for induction therapy. All studies were single-center analyses. rATG induction is utilized to delay calcineurin inhibitor initiation and to minimize or avoid steroids. Patients receiving rATG induction tended to have improved renal function compared with patients not receiving induction. Overall, rejection rates tended to be lower in recipients administered rATG. Regimens varied in each study, with most recipients receiving 2 to 3 doses of induction therapy.

CONCLUSIONS

rATG induction therapy may lead to improved renal function and lower rejection rates following liver transplant. The use of this medication can help avoid unwanted adverse effects from other immunosuppression agents. Because of the potential benefits with this induction agent, rATG may have a larger role in induction therapy for liver transplant recipients.

Simultaneous Liver-Kidney Transplantation

In 2014, simultaneous liver kidney transplants (SLK) accounted for 8.2 % of all liver transplants performed in the USA. Prior to introduction of the model of end stage liver disease (MELD) system, SLK accounted for 2.5 % in 2001 and only 1.7 % in 1990. Transplant centers have struggled to balance the moral and ethical aspects of SLK in the setting of organ scarcity with an algorithm that best qualifies patients for such treatment options. Few centers have even ventured into DCD territory for SLK. Advancement in immunosuppression protocols and treatment of HCV and HIV have impacted SLK over the years. Simulation modeling has allowed us to analyze the future impact of our decisions that are made today. All of these advancements have given, and will continue to give new perspectives to SLK. The purpose of this review article is to highlight these advances and bring to light the studies that have made this transplant option successful.