Alemtuzumab with Rapid Steroid Taper in Simultaneous Kidney and Pancreas Transplantation: Comparison to Induction with Antithymocyte Globulin

A comprehensive update of the metabolic and toxicological considerations for immunosuppressive drugs used during pancreas transplantation

INTRODUCTION

Despite significant advancements in immunosuppressive regimens and surgical techniques, the prevalence of adverse events related to immunosuppression remains a major challenge affecting the long-term survival rates of pancreas and kidney allografts.

AREAS COVERED

This article presents a comprehensive review of the literature and knowledge (Jan/2012-Feb/2023) concerning glucose metabolism disorders and nephrotoxicity associated with tacrolimus and mammalian target of rapamycin inhibitors (mTORi). Novel signaling pathways potentially implicated in these adverse events are discussed. Furthermore, we extensively examine the findings from clinical trials evaluating the efficacy and safety of tacrolimus, mTORi, and steroid minimization.

EXPERT OPINION

Tacrolimus-based regimens continue to be the standard treatment following pancreas transplants. However, prolonged use of tacrolimus and mTORi may lead to hyperglycemia and nephrotoxicity. Understanding and interpreting experimental data, particularly concerning novel signaling pathways beyond calcineurin-NFAT and mTOR pathways, can offer valuable insights for therapeutic interventions to mitigate hyperglycemia and nephrotoxicity. Additionally, critically analyzing clinical trial results can identify opportunities for personalized safety-based approaches to minimize side effects. It is imperative to conduct randomized-controlled studies to assess the impact of mTORi use and steroid-free protocols on pancreatic allograft survival. Such studies will aid in tailoring treatment strategies for improved transplant outcomes.

First World Consensus Conference on pancreas transplantation: Part II - recommendations

The First World Consensus Conference on Pancreas Transplantation provided 49 jury deliberations regarding the impact of pancreas transplantation on the treatment of diabetic patients, and 110 experts' recommendations for the practice of pancreas transplantation. The main message from this consensus conference is that both simultaneous pancreas-kidney transplantation (SPK) and pancreas transplantation alone can improve long-term patient survival, and all types of pancreas transplantation dramatically improve the quality of life of recipients. Pancreas transplantation may also improve the course of chronic complications of diabetes, depending on their severity. Therefore, the advantages of pancreas transplantation appear to clearly surpass potential disadvantages. Pancreas after kidney transplantation increases the risk of mortality only in the early period after transplantation, but is associated with improved life expectancy thereafter. Additionally, preemptive SPK, when compared to SPK performed in patients undergoing dialysis, appears to be associated with improved outcomes. Time on dialysis has negative prognostic implications in SPK recipients. Increased long-term survival, improvement in the course of diabetic complications, and amelioration of quality of life justify preferential allocation of kidney grafts to SPK recipients. Audience discussions and live voting are available online at the following URL address: http://mediaeventi.unipi.it/category/1st-world-consensus-conference-of-pancreas-transplantation/246.

Working towards an ERAS Protocol for Pancreatic Transplantation: A Narrative Review

Enhanced recovery after surgery (ERAS) initially started in the early 2000s as a series of protocols to improve the perioperative care of surgical patients. They aimed to increase patient satisfaction while reducing postoperative complications and postoperative length of stay. Despite these protocols being widely adopted in many fields of surgery, they are yet to be adopted in pancreatic transplantation: a high-risk surgery with often prolonged length of postoperative stay and high rate of complications. We have analysed the literature in pancreatic and transplantation surgery to identify the necessary preoperative, intra-operative and postoperative components of an ERAS pathway in pancreas transplantation.

Immunosuppression considerations in simultaneous organ transplant

Solid organ transplantation is a life-saving procedure for patients in the end stage of heart, lung, kidney, and liver failure. For patients with more than one failing organ, simultaneous organ transplantation has emerged as a viable treatment option. Immunosuppression strategies and outcomes for simultaneous organ transplant recipients have been reported, but often involve limited populations. Transplanting dual organs poses challenges in terms of balancing immunosuppression with immunologic risk and allograft damage from surgical complications. Furthermore, transplanting certain organs can impose considerations on the management of immunosuppression. For example, liver allografts may confer immunologic privilege and lower rates of rejection of other allografts. This review article evaluates immunosuppression strategies for simultaneous kidney-pancreas, liver-kidney, heart-kidney, heart-liver, heart-lung, lung-liver, and lung-kidney transplants. To date, no comprehensive review exists to address immunosuppressive strategies in simultaneous organ transplant populations. Our review summarizes the available literature and provides evidence-based recommendations regarding immunosuppression strategies in simultaneous organ transplant recipients.

Long-Term Infectious and Noninfectious Outcomes of Monthly Alemtuzumab as a Calcineurin Inhibitor- and Steroid-Free Regimen for Pancreas Transplant Recipients

Multiple doses of alemtuzumab for immunosuppressive therapy of patients with hematologic malignancies and hematopoietic stem cell transplant have been associated with a high rate of infection. In transplantation, limited alemtuzumab dosing has been successfully used as induction immunosuppression. The effect of multiple doses of alemtuzumab, used as maintenance therapy to minimize steroid and/or calcineurin inhibitor toxicity in solid organ transplant recipients, is unknown. We evaluated the infectious and noninfectious outcomes of 179 pancreas transplant recipients treated with alemtuzumab for induction and maintenance therapy (extended alemtuzumab exposure (EAE)) from 2/28/2003 through 8/31/2005, compared with 159 pancreas transplant recipients with standard induction and maintenance (SIM) therapy performed before (1/1/2002 until 12/31/2002) and after (1/1/2006 until 12/31/2006) the implementation of EAE. EAE was associated with higher risk of overall infections (hazard ratio (HR) 1.33 (1.06–1.66), P=0.01), bacterial infections (HR 1.33 (1.05–1.67), P=0.02), fungal infections (HR 1.86 (1.28–2.71), P < 0.01), and cytomegalovirus infections (HR 2.29 (1.39–3.77), P < 0.01). In addition, EAE was associated with higher risk of acute cellular rejection (HR 2.09 (1.46–2.99), P < 0.01). In conclusion, while a limited alemtuzumab dosing is safe and effective for induction therapy in pancreas transplantation, EAE combined with steroid and calcineurin minimization is associated with a high risk of infectious complications and acute cellular rejection.

Alemtuzumab Induction and Delayed Acute Rejection in Steroid-Free Simultaneous Pancreas-Kidney Transplant Recipients

Supplemental digital content is available in the text.

Background

The optimal immunosuppressive regimen in simultaneous pancreas-kidney transplant (SPKT) recipients that prevents acute rejection episodes (AREs) and allows optimal outcome remains elusive.

Methods

This cohort study assessed incidence and time to AREs in 73 consecutive SPKT recipients receiving alemtuzumab induction and steroid-free maintenance with tacrolimus and mycophenolate mofetil. A cohort with single high-dose antithymocyte globulin (ATG; n = 85) and triple therapy served as controls. In addition, we provided mechanistic insights in AREs after alemtuzumab depletion, including composition and alloreactivity of lymphocytes (flow cytometry and mixed lymphocyte reaction) plasma alemtuzumab levels (enzyme-linked immunosorbent assay), and maintenance drug exposure.

Results

Overall number of AREs at 3 years was significantly lower with alemtuzumab versus ATG induction (26.0% vs 43.5%; adjusted hazard ratio, 0.38; P = 0.029). Most AREs (94.6%) with ATG occurred within the first month, whereas 84.2% of AREs with alemtuzumab occurred beyond 3 months. Patients with and without an ARE in the steroid-free alemtuzumab group showed no differences in composition of lymphocytes, or in alemtuzumab levels. Of note, more than two thirds of these AREs were preceded by empiric tacrolimus and/or mycophenolate mofetil dose adjustments due to viral infections, leukopenia, or gastrointestinal symptoms.

Conclusions

Alemtuzumab induction resulted in a significant lower incidence of AREs. Empiric dose adjustments beyond 3 months in the absence of steroids carry a significant risk for subsequent rejection in SPKT recipients.

Incidence and management of leukopenia/neutropenia in 233 kidney transplant patients following single dose alemtuzumab induction

BACKGROUND

The purpose of this study was to determine the incidence and management strategies for post-transplant leukopenia/neutropenia in kidney recipients receiving alemtuzumab induction during the first year following transplantation.

METHODS

We prospectively identified 233 adult patients who underwent kidney transplantation with alemtuzumab induction at a single institution. The incidence and severity of leukopenia (white blood cell count [WBC] ≤2500/mm(3)) and neutropenia (absolute neutrophil count [ANC] ≤500/mm(3)) were evaluated at 1, 3, 6, and 12 months post-transplantation. We determined any association with cytomegalovirus (CMV) infection, graft rejection, and infections requiring hospitalization. We also reviewed interventions performed, including medication adjustments, treatment with granulocyte stimulating factor, and hospitalization.

RESULTS

The combined incidence of either leukopenia or neutropenia was 47.5% (n = 114/233) with an average WBC nadir of 1700 ± 50/mm(3) at 131.0 ± 8.5 days and an average ANC nadir of 1500 ± 100/mm(3) at 130.4 ± 9.6 days. No significant difference in graft rejection, CMV infection, or infections requiring hospitalization was found in the leukopenia/neutropenia group vs the normal WBC group (P = .3). The most common intervention performed for leukopenia/neutropenia group was prophylactic medication adjustment. Six patients (5.2%) required a change in >1 medication. The majority of these patients also required granulocyte stimulating factor (61.5%; 32/52), with an average of 2.5 doses given. A total of 25 patients (21.9%) required hospitalization due to leukopenia/neutropenia with an average length of stay of 6 days.

CONCLUSIONS

Kidney transplant patients receiving alemtuzumab induction required significant interventions due to leukopenia/neutropenia in the first year post-transplantation. These results suggest the need for additional studies aimed at defining the optimum management strategies of leukopenia/neutropenia in this population.

Successful Combined Pancreas Fourth-Kidney Third and Pancreas Third-Kidney Second Transplantation: A Case Report

Extremely few reports have been published on experience with multiple combined pancreas-kidney re-transplantation including long-term results. We here analyze our experience with two patients following successful combined pancreas fourth-kidney third and pancreas third-kidney second transplantation.

METHODS

Patient and graft survival as well as graft function and major complications were recorded. Patient 1 (women, 47 years) underwent combined pancreas fourth-kidney third transplantation after previous removal of the first and second renal and the second pancreatic grafts. Patient 2 (men, 51 years) underwent combined pancreas third-kidney second transplantation after nephrectomy of the first renal graft. Immunosuppression consisted of induction with alemtuzumab and maintenance with tacrolimus, mycophenolate mofetil/mycophenolic acid and steroids.

RESULTS

After a follow-up of 44 and 49 months, respectively, both patients are doing well with stable graft function. Leukopenia, thrombocytopenia, bacterial sepsis, and chronic hepatitis C as major complications were controllable.

CONCLUSIONS

Multiple pancreas-retransplantations combined with simultaneous renal transplantation are feasible. Meticulous immunosuppression, careful monitoring, and excellent patient adherence are of crucial importance.

New directions for rabbit antithymocyte globulin (Thymoglobulin(®)) in solid organ transplants, stem cell transplants and autoimmunity

In the 30 years since the rabbit antithymocyte globulin (rATG) Thymoglobulin^® was first licensed, its use in solid organ transplantation and hematology has expanded progressively. Although the evidence base is incomplete, specific roles for rATG in organ transplant recipients using contemporary dosing strategies are now relatively well-identified. The addition of rATG induction to a standard triple or dual regimen reduces acute cellular rejection, and possibly humoral rejection. It is an appropriate first choice in patients with moderate or high immunological risk, and may be used in low-risk patients receiving a calcineurin inhibitor (CNI)-sparing regimen from time of transplant, or if early steroid withdrawal is planned. Kidney transplant patients at risk of delayed graft function may also benefit from the use of rATG to facilitate delayed CNI introduction. In hematopoietic stem cell transplantation, rATG has become an important component of conventional myeloablative conditioning regimens, following demonstration of reduced acute and chronic graft-versus-host disease. More recently, a role for rATG has also been established in reduced-intensity conditioning regimens. In autoimmunity, rATG contributes to the treatment of severe aplastic anemia, and has been incorporated in autograft projects for the management of conditions such as multiple sclerosis, Crohn’s disease, and systemic sclerosis. Finally, research is underway for the induction of tolerance exploiting the ability of rATG to induce immunosuppresive cells such as regulatory T-cells. Despite its long history, rATG remains a key component of the immunosuppressive armamentarium, and its complex immunological properties indicate that its use will expand to a wider range of disease conditions in the future.

Immunosuppression for pancreas transplantation with an emphasis on antibody induction strategies: review and perspective

A review of recent literature was performed to identify trends and evaluate outcomes with respect to immunosuppression in pancreas transplantation (PTX). In the past decade, the majority of PTXs were performed with depleting antibody induction, particularly in the setting of either calcineurin inhibitor minimization, corticosteroid withdrawal or both. Maintenance immunosuppression consisted of predominantly tacrolimus (TAC)/mycophenolatemofetil, TAC/mycophenolic acid or TAC/sirolimus with or without corticosteroids. Depending on PTX category, donor and recipient risk factors, case mix and immunosuppressive regimen, the 1-year incidence of acute rejection has decreased to 5-20%. Current 1-year rates of immunological pancreas graft loss range between 1.8 and 6%. Depleting antibody induction and either TAC/mycophenolatemofetil or TAC/sirolimus maintenance therapy with early steroid withdrawal have become the mainstay of immunosuppression in PTX. However, the development of non-nephrotoxic, nondiabetogenic, and nongastrointestinal toxic regimens is highly desirable to improve quality of life in all solid organ transplant recipients.

Alemtuzumab induction in simultaneous pancreas and kidney transplantation

BACKGROUND

Alemtuzumab (AZ) is a monoclonal anti-CD52 antibody used as an induction agent in organ transplantation. Few studies have analyzed this agent in the context of simultaneous kidney-pancreas transplantation (SPKT).

METHODS

We examined US registry data of SPKT recipient outcomes from January 2002 to October 2009 stratified by induction agent including AZ, other T-cell-depleting agents combined (T cell), IL2 receptor blockade (IL-2RAb), and no induction (none).

RESULTS

Of 6860 SPKT recipients, induction therapy was AZ in 10%, T cell in 49%, IL-2RAb in 18%, and none in 22%. On multivariate analysis, there were no significant differences in overall patient survival, pancreas or renal allograft survival, or delayed renal graft function for the three induction groups compared with no induction. Rehospitalization within six months of transplantation occurred more often with AZ (51%) T cell (52%), and IL-2RAB (45%) compared with none (41%; p < 0.0001). On multivariate analysis, there was a significant higher odds of six-month rehospitalization with AZ (aOR 1.40, 95%CI 1.14-1.71), IL-2RAb (aOR 1.20, 95%CI 1.01-1.42-1.20), and other T-cell-depleting agents (aOR 1.50, 95%CI 1.31-1.73) compared with none. Median length of stay was significantly shorter in the AZ (8 d) compared with the IL-2RAb (9 d), T cell (10 d), and none (10 d) groups (p < 0.0001).

CONCLUSIONS

There are no differences in patient, pancreas or renal allograft survival using AZ induction. AZ may confer an advantage in the perioperative period as evidenced by a decreased hospital length of stay. However, this benefit may be lost due to more frequent rehospitalizations.

Trends in immunosuppression after pancreas transplantation: what is in the pipeline?

PURPOSE OF REVIEW

To provide an overview of currently available immunosuppressive strategies and novel therapeutic developments in pancreas transplantation.

RECENT FINDINGS

From 1966 through 2012 more than 30 000 pancreas transplantations have been performed around the world with excellent patient and graft survival. However, drug-related side effects and toxicities remain to negatively affect long-term outcomes. At present, more than 90% of pancreas transplant recipients receive induction therapy with depleting or nondepleting antibodies. The most widely used maintenance protocols are based on tacrolimus and mycophenolate mofetil with early or delayed corticosteroid withdrawal. In case of documented side effects related to this standard protocol, several regimens are actively pursued to switch to mammalian target of rapamycin inhibitors as well as to attempt initial calcineurin inhibitor avoidance and immunosuppression minimization. In addition, the recent documented negative impact of donor-specific antibodies on pancreas transplantation outcome has resulted in new treatment protocols for antibody-mediated rejection including intravenous immunoglobulins, anti-CD20 antibodies and protease inhibitors.

SUMMARY

Implementation of novel therapeutic strategies and combination protocols to reduce or avoid drug toxicities and immune-related complications that are evaluated in prospective and randomized trials is requested to improve outcomes after pancreas transplantation.

Infections associated with monoclonal antibody and fusion protein therapy in humans

Monoclonal antibodies (mAbs), especially those that interact with immune or hematologic leukocyte membrane targets, have changed the outcome of numerous diseases. However, mAbs can block or reduce immune cells and cytokines, and can lead to increased risk of infection. Some of these risks are predictable and can be explained by their mechanisms of action. Others have been observed only after the mAbs were licensed and used extensively in patients. In this review, we focus on infectious complications that occur upon treatment with mAbs or Fc-containing fusion proteins targeting leukocyte membrane proteins, including CD52, CD20, tumor necrosis factor, VLA4, CD11a and CTLA4. We report their known infectious risks and the recommendations for their use. Although most of these drugs are clinically safe when the indications are respected, we emphasize the need for regular updating of pharmacovigilance data.