Randomized comparison of triple therapy and antithymocyte globulin induction treatment after simultaneous pancreas-kidney transplantation

Dehydroxymethylepoxyquinomicin, a novel nuclear factor-κB inhibitor, prevents the development of cyclosporine A nephrotoxicity in a rat model

Background

Cyclosporine A (CsA) is an essential immunosuppressant in organ transplantation. However, its chronic nephrotoxicity is an obstacle to long allograft survival that has not been overcome. Nuclear factor-κB (NF-κB) is activated in the renal tissue in CsA nephropathy. In this study, we aimed to investigate the effect of the specific NF-κB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ), in a rat model of CsA nephrotoxicity.

Methods

We administered CsA (15 mg/kg) daily for 28 days to Sprague-Dawley rats that underwent 5/6 nephrectomy under a low-salt diet. We administered DHMEQ (8 mg/kg) simultaneously with CsA to the treatment group, daily for 28 days and evaluated its effect on CsA nephrotoxicity.

Results

DHMEQ significantly inhibited NF-κB activation and nuclear translocation due to CsA treatment. Elevated serum urea nitrogen and creatinine levels due to repeated CsA administration were significantly decreased by DHMEQ treatment (serum urea nitrogen in CsA + DHMEQ vs CsA vs control, 69 ± 6.4 vs 113.5 ± 8.8 vs 43.1 ± 1.1 mg/dL, respectively, p < 0.0001; serum creatinine in CsA + DHMEQ vs CsA vs control, 0.75 ± 0.02 vs 0.91 ± 0.02 vs 0.49 ± 0.02 mg/dL, respectively, p < 0.0001), and creatinine clearance was restored in the treatment group (CsA + DHMEQ vs CsA vs control, 2.57 ± 0.09 vs 1.94 ± 0.12 vs 4.61 ± 0.18 ml/min/kg, respectively, p < 0.0001). However, DHMEQ treatment did not alter the inhibitory effect of CsA on urinary protein secretion. The development of renal fibrosis due to chronic CsA nephrotoxicity was significantly inhibited by DHMEQ treatment (CsA + DHMEQ vs CsA vs control, 13.4 ± 7.1 vs 35.6 ± 18.4 vs 9.4 ± 5.4%, respectively, p < 0.0001), and these results reflected the results of renal functional assessment. DHMEQ treatment also had an inhibitory effect on the increased expression of chemokines, monocyte chemoattractant protein-1, and chemokine (c-c motif) ligand 5 due to repeated CsA administration, which inhibited the infiltration of macrophages and neutrophils into the renal tissue.

Conclusions

These findings suggest that DHMEQ treatment in combination therapy with CsA-based immunosuppression is beneficial to prevent the development of CsA-induced nephrotoxicity.

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.

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.

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.

Rabbit antithymocyte globulin (thymoglobulin): 25 years and new frontiers in solid organ transplantation and haematology

The more than 25 years of clinical experience with rabbit antithymocyte globulin (rATG), specifically Thymoglobulin, has transformed immunosuppression in solid organ transplantation and haematology. The utility of rATG has evolved from the treatment of allograft rejection and graft-versus-host disease to the prevention of various complications that limit the success of solid organ and stem cell transplantation. Today, rATG is being successfully incorporated into novel therapeutic regimens that seek to reduce overall toxicity and improve long-term outcomes. Clinical trials have demonstrated the efficacy and safety of rATG in recipients of various types of solid organ allografts, recipients of allogeneic stem cell transplants who are conditioned with both conventional and nonconventional regimens, and patients with aplastic anaemia. Over time, clinicians have learnt how to better balance the benefits and risks associated with rATG. Advances in the understanding of the multifaceted mechanism of action will guide research into new therapeutic areas and future applications.

Minimization and withdrawal of steroids in pancreas and islet transplantation

For reducing the corticosteroid (CS)-related side-effects, especially cardiovascular events, CS-sparing protocols have become increasingly common in pancreas transplantation (PT). Lympho-depleting induction antibodies, such as rabbit anti-thymocyte globulin (rATG) or alemtuzumab, have been widely used in successful trials. The results of various CS-sparing protocols combining calcineurin inhibitors (CNI) and mycophenolate or sirolimus, have been mixed for rejection and survival rates. Most of the studies were uncontrolled trials of low-risk patients, therefore the grade of evidence is limited. Large-scale prospective studies with long-term follow up are necessary to assess risks and benefits of CS-sparing regimens in PT before recommending such strategies as standard practice. Islet allo-transplantation for patients with brittle type 1 diabetes mellitus, less invasive and safer procedure than PT, has been attempted since late 1980s, but diabetogenic immunosuppressants at maintenance, mainly CS and high-dose CNI, prevented satisfactory results (10% insulin-independence at 1-year post-transplant). Since 2000, CS-free and CNI-reducing protocols, including more potent induction [daclizumab, OKT3gamma1(ala-ala) anti-CD3 antibody, rATG] and maintenance (sirolimus, mycophenolate) agents, have significantly improved short-term outcomes whereas long-term are still inadequate (from 80% to 20% insulin-independence from 1- to 5-year post-transplant). Main limitations are allo- and autoimmunity, immunosuppression-related islet and systemic toxicity and transplant site unsuitability, which tolerogenic protocols and biotechnological solutions may solve.

Minimization protocols in pancreas transplantation

Diagnosis of immunologic injury (acute and chronic) is much more difficult in pancreas transplants when compared with transplants of other organs. Currently, the immunosuppressive regimen for induction involves calcineurin inhibitors (CNI), antimetabolites and corticosteroids (Cs). This strong and nonspecific regimen does not take into consideration pancreas specificities (i.e. the need to avoid diabetogenic compounds). For obvious reasons, CNI might be calling for review, if permanently indicated in recipients of solitary pancreas with mild renal dysfunction. CNI as well as corticosteroids may induce hyperglycemia and contribute to differential diagnosis of a rejection process. However, in spite of the benefits accruing from withdrawal of above immunosuppressive agents, minimization or avoidance of these drugs could be dangerous and may end up with graft loss (i.e. antibody-mediated process). Long-term results of pancreas transplantation are now achieving comparable survival rates similar to the transplant of traditional organs such as kidney and liver. As a consequence, the physicians' objectives are to prolong the patient's quality of life and organ function as long as possible. Weaning strategies in regard to CNI and steroids are tested. Sirolimus, everolimus, CTLA-4 Ig, etc, are agents known to be either both nonnephrotoxic and nondiabetogenic or less so when compared with CNI. Their impact on pancreas transplantation is beginning to be evaluated. Large randomized trials in all pancreas categories, with long-term clinical and histologic results, are mandatory to establish new guidelines for immunosuppressive regimens for pancreas transplantation.

A randomized trial of alemtuzumab vs. anti-thymocyte globulin induction in renal and pancreas transplantation

The role of alemtuzumab as an immunosuppressive agent is evolving. We conducted a prospective randomized trial comparing alemtuzumab and rabbit anti-thymocyte globulin (rATG) induction in adult kidney and pancreas transplantation using similar maintenance immunosuppression. Between February 1, 2005 and June 15, 2006 (median follow-up six months), 98 patients were randomized either to alemtuzumab (n = 48) or to rATG (n = 50) induction; 77 (79%) underwent kidney alone (KA) transplant, 17 (17%) pancreas-kidney transplant, and four (4%) pancreas after kidney transplant. Of 77 KA transplants, 66 (86%) were from deceased donors and 31 (40%) from expanded criteria donors (ECD). Re-transplantation, HLA-match, antibody titer, ECD, race, cytomegalovirus status, steroid use, delayed graft function, preservation time, and immunological risk were similar between the two induction groups. Patient, kidney, and pancreas graft survival rates were 100%, 96%, and 95%, respectively. Survival, initial length of stay, delayed graft function, and overall acute rejection rates were similar between alemtuzumab and rATG groups, but acute rejection occurred in nine (20%) rATG patients compared with zero (0%) alemtuzumab patients who received KA transplants (p = 0.007). Mean induction costs differed in the alemtuzumab ($1474) and rATG ($4996, p < 0.001) groups. In the short term after kidney and pancreas transplantation, alemtuzumab and rATG induction therapies are similarly safe and effective.

The long-term survival of simultaneous pancreas and kidney transplant with basiliximab induction therapy

Interleukin-2 receptor (IL2R) antibody has emerged as an attractive induction therapy for organ transplant. However, the long-term outcome of basiliximab induction in simultaneous pancreas and kidney (SPK) transplant remains speculative. We retrospectively analyzed the long-term survivals of 91 consecutive SPK recipients with basiliximab as induction, combination of steroid, tacrolimus (TAC) and mycophenolate acid (MFA)--either mycophenolate mofetil (MMF) or sodium mycophenolate (myfortic) as maintenance. At one, three, five, and seven-yr, the actual patient survival rate were 91.2%, 90.3%, 88.1%, and 88.2%, respectively; kidney graft survivals were 90.1%, 84.7%, 78.6%, and 70.6%, respectively; and pancreas graft survivals were 86.8%, 80.6%, 71.4%, and 58.8% respectively. There was a low incidence of rejection and CMV infection. Basiliximab induction with TAC, MFA, and steroid maintenance therapy can provide excellent long-term outcome for SPK recipients.

A comparison of long-term survivals of simultaneous pancreas-kidney transplant between African American and Caucasian recipients with basiliximab induction therapy

African Americans (AA) have traditionally been thought to have higher immunologic risk than Caucasians (CA) for rejection and allograft loss. The impact of ethnicity on the outcome of simultaneous pancreas-kidney (SPK) transplant with basiliximab induction has not been reported. In this study, we retrospectively analyze the long-term results of 36 AA and 55 CA recipients of primary SPK. The actual patient survival rates of AA and CA groups were 91.7% vs. 90.1% at 1 year, 93.3% vs. 88.1% at 3 years, and 94.4% vs. 83.3% at 5 years. The actual kidney survival of AA and CA were 91.7% vs. 89.1% at 1 year, 90% vs. 81% at 3 years, and 83.3% vs. 75% at 5 years. The actual pancreas survival of AA and CA were 88.9% vs. 85.5% at 1 year, 83.3% vs. 78.6% at 3 years and 72.2% vs. 70.8% at 5 years. Death-censored analyses also found no difference in pancreas and kidney graft survival rates over 5 years. Higher rejection rate, but the same low CMV infection, and comparable quality of graft function were noted in AA group. AA may not have worse long-term outcomes than CA recipients of SPK with basiliximab induction and tacrolimus (TAC), mycophenolate acid (MFA) and steroid maintenance immunotherapy.

Update on Pharmacoeconomics in Transplantation

Purpose

To provide current information on pharmacoeconomic outcomes in transplantation for the past 6 years.

Methods

An extensive literature search was undertaken using PubMed and other authenticated Internet sources. Key words used to elicit pertinent studies were “pharmacoeconomics,” “transplantation,” “cost-effectiveness,” “cost-benefit,” “cost-minimization” and “cost-utility” analyses. Studies included in the review contain updated pharmacoeconomic data generated during the past 6 years on economic, clinical, and humanistic outcomes. These data are used to describe and analyze the cost of drug therapy used in transplantation.

Results

Background information is included in the review to provide a context from which to evaluate new study material. Data extracted from the studies include significant findings and study limitations. Data were stratified into understanding pharmacoeconomic methods and their application to transplantation, maintenance and induction therapies, and management of and costs associated with adverse events and quality-of-life issues.

Conclusions

Continued evolution of pharmacoeconomic analysis is needed so that optimal care can be provided in the most cost-effective manner. Pharmacoeconomic study, done rationally and logically, is an indispensable tool in determining optimal transplantation regimens.

Selective unresponsiveness to beta cell autoantigens after induction immunosuppression in pancreas transplantation with anti-interleukin-2 receptor antibody versus anti-thymocyte globulin

Pancreas transplantation in type 1 diabetes patients could result in (re)activation of allo- and autoreactive T lymphocytes. Anti-thymocyte globulin (ATG) induction treatment is a successful, but broadly reactive anti-lymphocyte therapy used in pancreas and islet transplantation. A more selective alternative is daclizumab, a monoclonal antibody directed against the interleukin-2 receptor (CD25) on activated lymphocytes. We tested the hypothesis that daclizumab is more selective and has less immunological side effects than ATG. Thirty-nine simultaneous pancreas-kidney transplantation patients with type 1 diabetes were randomized for induction therapy with ATG or daclizumab. Auto- and recall immunity was measured cross-sectionally by lymphocyte stimulation tests with a series of auto- and recall antigens in 35 successfully transplanted patients. T cell autoimmunity to islets was low in both groups, except for a marginal but significantly higher reactivity against glutamic acid decarboxylase (GAD)65 in daclizumab-treated patients. The memory responses to recall antigens were significantly higher in the daclizumab-treated group compared to ATG-treated patients, specifically against purified protein derivative (PPD) (anti-bacterial immunity), Haemophilus influenzae virus matrix protein-1 (anti-viral immunity) and p53 [anti-tumour (auto)immunity]. These data imply that daclizumab is more specifically affecting diabetes-related immune responses than ATG. The autoimmunity is affected effectively after daclizumab induction, while memory responses towards bacterial, viral and tumour antigens are preserved.

Long-Term Cell Monitoring of Kidney Recipients After an Antilymphocyte Globulin Induction With and Without Steroids

BACKGROUND

Because of several side effects, the corticosteroid usage has been minimized in kidney transplantation. The increased acute rejection episodes associated with their withdrawal may counterbalance with induction treatment using polyclonal antilymphocyte globulin (ALG). The effects of ALG on blood cell phenotype have already been the subject of several reports. However, to date, no data are available concerning the comparison of blood phenotype when ALG is given with or without steroids and no gene profiling study has been performed.

METHODS

We report here on a longitudinal blood cell analysis of a selected cohort of kidney recipients enrolled in a randomized study of steroid avoidance or withdrawal (during 6 months) during ALG induction.

RESULTS

In the two groups, ALG quickly and massively depleted all the T cells and natural killer cells, but not B cells. Interestingly, the lymphopenia-driven homeostatic proliferation of CD4 and CD8T cells strongly differed with persistent low CD4 (including CD25CD4) T-cell counts. Effector memory CD8T cells reappeared rapidly. ALG induced apoptosis-associated molecules and increased myeloid cell genes. However, few genes were found differentially expressed with a low fold ratio between the two groups during and at distance of corticotherapy.

CONCLUSION

Thus initial steroid avoidance or withdrawal associated with ALG induction has a weak influence on phenotype and transcriptional pattern of blood leukocytes. In contrast, ALG therapy induces an early and strong depletion of all T-cell subsets with contrasted long-lasting homeostatic regulation.

Severe graft rejection, increased immunosuppression, and active CMV infection in renal transplantation

Associations between active cytomegalovirus (CMV) infection, graft rejection, rejection therapy, and clinical signs and symptoms have been shown repeatedly. However, the causes and the sequence of events remain an area of debate. Two hundred twenty five patients with cadaveric renal transplant were included in the present study. Clinical signs and symptoms, and the development of active CMV infections were recorded during the first 3 months after renal transplantation. CMV monitoring by pp65-antigenemia was performed followed by preemptive antiviral therapy. Delayed graft function and severe graft rejection followed by anti T-cell antibody therapy was associated with the development of active CMV infection. In contrast, the induction therapy with anti-T-cell antibodies was not associated with more active CMV infections. Post-transplant morbidity determined by fever, pneumonia, and duration of hospital stay was increased significantly in patients with active CMV infection. However, in times of preemptive antiviral therapy an increased morbidity occurred in association with severe graft rejection and not with active CMV infection alone. In patients with renal transplantation and preemptive antiviral therapy, the morbidity was no more influenced by the CMV serostatus although the prevalence of active CMV infection was obviously different between CMV exposed (D+/R+,D+/R-, D-/R+) and unexposed (D-/R-) patients. Severe graft rejection and increased immunosuppression could stimulate cooperatively active CMV infections whereas immunosuppression alone may not be as effective. Prevention of severe graft rejection may be important to decrease early post-transplant morbidity and also the development of active CMV infections after renal transplantation.

Choice of antibody immunotherapy influences cytomegalovirus viremia in simultaneous pancreas-kidney transplant recipients

OBJECTIVE

Simultaneous pancreas-kidney (SPK) transplantation in type 1 diabetic patients requires immunotherapy against allo- and autoreactive T-cells. Cytomegalovirus (CMV) infection is a major cause for morbidity after transplantation and is possibly related to recurrent autoimmunity. In this study, we assessed the pattern of CMV viremia in SPK transplant recipients receiving either antithymocyte globulin (ATG) or anti-CD25 (daclizumab) immunosuppressive induction therapy.

RESEARCH DESIGN AND METHODS

We evaluated 36 SPK transplant recipients from a randomized cohort that received either ATG or daclizumab as induction therapy. Patients at risk for CMV infection received oral prophylactic ganciclovir therapy. The CMV DNA level in plasma was measured for at least 180 days using a quantitative real-time PCR. Recipient peripheral blood mononuclear cells were cross-sectionally HLA tetramer-stained for CMV-specific CD8(+) T-cells.

RESULTS

Positive CMV serostatus in donors was correlated with a higher incidence of CMV viremia than negative serostatus. In patients at risk, daclizumab induction therapy significantly prolonged CMV-free survival. CMV viremia occurred earlier and was more severe in patients with rejection episodes than in patients without rejection episodes. CMV-specific CD8(+) T-cell counts were significantly lower in patients developing CMV viremia than in those who did not.

CONCLUSIONS

Despite their comparable immunosuppressive potential, daclizumab is safer than ATG regarding CMV infection risk in SPK transplantation. ATG-treated rejection episodes are associated with earlier and more severe infection. Furthermore, high CMV-specific tetramer counts reflect antiviral immunity rather than concurrent viremia because they imply low viremic activity. These findings may prove valuable in the discussion on both safety of induction therapy and recurrent autoimmunity in SPK and islet transplantation.

An evidence-based analysis of simultaneous pancreas-kidney and pancreas transplantation alone

While pancreas transplantation has evolved within two decades from a frustrating and poorly-accepted therapeutic option to a highly successful procedure, the respective benefits of the successive surgical and immunosuppressive developments have remained unclear. The aim of this study was to determine using an evidence-based methodology, which novel approaches have contributed to the current results and whether pancreas transplantation is cost-effective. Out of 2481 articles, 102 analyzed either surgical or immunosuppressive aspects of pancreas transplantation. Urological complications were more frequent in bladder over enteric drainage (range: 62-63% vs. 12-20%, p = 0.0001), but without significant difference in patient or graft survival. Portal drainage was associated with a trend toward fewer complications and better hyperinsulinemia control over systemic drainage in retrospective studies. Immunosuppression combining induction therapy, a calcineurin inhibitor, mycophenolate mophetil (MMF) and corticosteroids were associated with a 40% decreased incidence of rejection (p = 0.01) and an increase in graft survival above 90% at 1 year (p < 0.05). Pancreas transplantation is highly cost-effective compared to conservative alternatives. We conclude that despite a paucity of large studies, enteric drainage should be recommended but the benefits of portal venous drainage remain debated. Quadruple immunosuppression protocols including induction therapy should be the standard regimen.

Polyclonal Antibody-Induced Serum Sickness in Renal Transplant Recipients: Treatment with Therapeutic Plasma Exchange

Serum sickness is an immune-complex mediated illness that frequently occurs in patients after polyclonal antibody therapy (ATGAM or thymoglobulin). Serum sickness presents with significant morbidity but is self-limited and resolves with prolonged steroid therapy. We present five renal transplant patients who developed serum sickness after polyclonal antibody treatment with severe symptoms that persisted after being started on systemic steroids. These patients underwent one or two courses of therapeutic plasma exchange (TPE) with subsequent complete resolution of their symptoms. Renal transplant recipients with serum sickness after polyclonal antibody therapy may benefit from TPE by accelerating their time to recovery and thereby reducing overall morbidity.

Steroid avoidance versus steroid withdrawal after simultaneous pancreas-kidney transplantation

Two steroid-sparing immunosuppressive regimens were prospectively compared in recipients of simultaneous pancreas-kidney transplants, one did not include steroids at all and the other included steroids for the first 3 months following transplantation. All patients received rabbit anti-thymocyte globulin, mycophenolate mofetil (MMF) and cyclosporine. Fifty patients were randomised in an open-label, single center and prospective study. The incidence of biopsy-proven acute rejection during the first 12 months after transplantation was the primary endpoint of the study. The incidence of biopsy-proven acute rejection was 4% in both groups. No statistically significant difference in patient (96 and 100%), kidney (96 and 100%) or pancreas (84 and 92%) survival was observed 1 year after transplantation in the steroid avoidance and steroid withdrawal groups, respectively. The total number of adverse events (including severe ones), length of hospitalization and infectious episodes did not differ between groups. Blood glucose and insulin levels, lipid profile and hemoglobin A1C levels did not differ statistically between the two groups. However, the 1-year serum creatinine level was significantly higher in the steroid avoidance group (132 vs. 114 micromol/L; p = 0.02). Steroid avoidance and steroid withdrawal 3 months after transplantation are safe and effective regimens for diabetic patients with pancreas-kidney transplants.

Sequential protocols using basiliximab versus antithymocyte globulins in renal-transplant patients receiving mycophenolate mofetil and steroids

BACKGROUND

Sequential anti-thymocyte globulins (ATG)/cyclosporine immunosuppression has two main advantages: delayed introduction of the nephrotoxic drug cyclosporine and prevention of acute rejection. Basiliximab, a recently developed chimeric monoclonal antibody that selectively depletes the minor subpopulation of activated T lymphocytes, has been shown to reduce the incidence of acute rejection when used with cyclosporine introduced on day 1.

METHODS

This open, randomized, multicenter study was undertaken to compare the safety and efficacy of ATG versus basiliximab induction therapy (IT) with delayed introduction of cyclosporine for microemulsion (Neoral) in 105 low immunologic risk renal-transplant patients receiving mycophenolate mofetil and steroids.

RESULTS

One-year patient and graft survival rates were 98.1% and 94.2%, respectively, in the basiliximab group (n = 52), and 98.1% and 96.2% in the ATG group (n = 53). The incidence of biopsy-confirmed acute rejection was comparable (basiliximab 9.6%, ATG 9.4%), as were key parameters of renal function, notably serum creatinine levels, time-to-nadir serum creatinine, and the number of patients requiring posttransplantation dialysis (basiliximab 28.8%, ATG 30.2%). However, significantly fewer patients in the basiliximab group experienced cytomegalovirus (CMV) infection, leukopenia, and thrombocytopenia, and this without any significant difference in any other key safety parameters (including the incidences of serum sickness, fever, lymphoma, and infections in general).

CONCLUSIONS

Both ATG and basiliximab, when used for IT in a sequential protocol, are equally effective in terms of graft and patient survival as well as at preventing acute rejection. However, basiliximab is associated with a lower incidence of certain key adverse events, namely CMV infection, leukopenia, and thrombocytopenia.

Historical controlled trial of OKT3 versus basiliximab induction therapy in simultaneous pancreas-renal transplantation

Simultaneous pancreas-kidney (SPK) transplant recipients are at high immunological risk of rejection. Antibody induction is beneficial but lymphocyte-depleting therapy is associated with a high incidence of side-effects. We performed a historical controlled trial to compare OKT3 versus anti-CD25 antibody (basiliximab) induction therapy with regard to patient, kidney and pancreas survival, as well as to examine for any differences in acute rejection, graft function, and infective complications. Twenty-eight consecutive SPK transplants were performed at the Monash Medical Centre between December 1997 and November 2001. Anti CD3 monoclonal antibody (OKT3) was used prior to March 2000 (n = 12) and basiliximab was used after (n = 16), both in combination with cyclosporin, mycophenolate, and prednisolone. A retrospective comparison of outcomes was performed. At 6 months, patient (100 vs 100%), kidney (91.7 vs 91.7%) and pancreas (75 vs 83.3%) survival were similar in the OKT3 and basiliximab groups, respectively. A minority of subjects in each group remained free from rejection (42% basiliximab vs 25% on OKT3, P = NS). Renal function was superior in the basiliximab group (mean calculated creatinine clearance 79.4 +/- 11.9 vs 54.5 +/- 15.9 mL/min for basiliximab vs OKT3, P < 0.001). The incidence of major opportunistic infection was lower in basiliximab-treated patients (9 vs 50% in the OKT3 group, P = 0.033). Basiliximab was associated with similar 6-month patient, kidney and pancreas survival, superior renal function and less opportunistic infection as compared with OKT3 induction therapy in SPK transplants. Basiliximab is at least as effective and is safer than OKT3 for induction therapy in SPK transplantation.

Metabolic effects of a corticosteroid-free immunosuppressive regimen in recipients of pancreatic transplant

BACKGROUND

A corticosteroid (CS)-free immunosuppressive regimen may be considered less diabetogenic than treatments including CSs principally after pancreas transplantation.

METHODS

To test whether a CS-free immunosuppressive treatment is metabolically superior to a regimen including CSs, we prospectively studied 19 CS-free simultaneous pancreas and kidney (SPK) transplant recipients (body mass index=22+/-1 kg/m2; cyclosporine dose=400+/-19 mg/kg/day; azathioprine dose=77+/-8 mg/day; basal plasma C-peptide=1.3+/-0.12 ng/mL) and 12 matched CS-treated SPK transplant recipients (prednisone dose=9+/-1 mg/day; basal C-peptide=2.2+/-0.2 ng/mL) by means of the 6,6-2H(2)-glucose infusion and the euglycemic insulin clamp (1 mU/kg/min, insulin infusion rate). In addition, six renal transplant recipients receiving a CS-free regimen were also studied as a control group.

RESULTS

In the postabsorptive state, CS-treated SPK transplant recipients demonstrated comparable plasma glucose levels but higher plasma insulin levels than CS-free SPK transplant recipients. Plasma triglyceride levels were significantly higher in CS-treated SPK patients than in CS-free SPK patients (1.16+/-0.16 mg/dL vs. 0.88+/-0.08; P<0.05). High-density lipoprotein and apoprotein A(1) levels were similar in both groups. No difference was observed in pyruvate, lactate, beta-OH-butyrate, and basal endogenous glucose production in all three groups of patients studied. During euglycemic hyperinsulinemia, the inhibition of endogenous glucose production and the stimulation of tissue glucose disposal were not statistically different among the three groups.

CONCLUSIONS

SPK recipients receiving chronic low-dose CS maintenance therapy do not present a lower glucose disposal than CS-free recipients. Nonetheless, this is obtained at the expense of a higher endogenous insulin secretion, which can cause an alteration of the triglyceride profile.

Thymoglobulin for induction or rejection therapy in pancreas allograft recipients: a single centre experience

PURPOSE

To review the safety and efficacy of thymoglobulin in pancreas transplant patients receiving tacrolimus and mycophenolate mofetil.

METHODS

Retrospective, single centre analysis of 45 patients transplanted between 1995 and 2000 who received 54 courses of thymoglobulin, including 36 courses in 29 solitary pancreas transplant recipients (16 pancreas alone, 13 pancreas after kidney transplants) and 18 courses in 16 simultaneous kidney-pancreas transplant patients. Thirty-two patients (71%) were primary pancreas transplants, 10 (22%) were second transplants and three (7%) were third transplants. Of the 54 treatment courses, 19 (35%) were for induction, 27 (50%) were for primary rejection and eight (15%) were rescue therapy for rejection. All rejection episodes were biopsy-proven in at least one organ.

RESULTS

The median thymoglobulin dose was 1.5 mg/kg/d with a mean of six doses (range 3-10). Dose reduction or interruption was required in 28 courses (52%), most often due to leukopenia (n = 24), fever (n = 2) and thrombocytopenia (n = 2). Thymoglobulin was resumed in all but three patients, two with persistent fever and one with infection. Infectious complications (n = 25) occurred in 17 patients (38%) within 30 days and included bacterial (n = 16), cytomegalovirus (n = 4), polyoma (n = 1), fungal (Candida albicans, n = 1), toxoplasmosis (n = 1) and ehrlichiosis (n = 2). Post-transplant lymphoproliferative disease occurred in two patients (4%) at a mean of 70 d post-thymoglobulin treatment. In the 19 patients that received thymoglobulin induction, one simultaneous kidney-pancreas transplant, two pancreas alone and four pancreas after kidney transplant recipients developed rejection (37% incidence), while all remaining patients followed by surveillance protocol biopsies were rejection-free. In the 35 patients that received thymoglobulin for rejection, reversal occurred in 26 of the patients (74%). Rejection recurred within 30 d in five patients and post-treatment biopsies revealed persistent rejection in three of 20 pancreas and two of eight renal biopsies. After a mean follow-up of 6 months, the actual patient and pancreas graft survival rates were 93% and 71%, respectively.

CONCLUSION

Thymoglobulin was effective as induction therapy in high-risk pancreas transplant recipients, and resulted in initial reversal of rejection in 74% of patients. Dose adjustments were required in over half the cases and were usually due to leukopenia. Infections occurring subsequent to thymoglobulin were not uncommon and reflected the immunosuppressive burden of the patient population.

Mycophenolate mofetil does not modify the incidence of cytomegalovirus (CMV) disease after kidney transplantation but prevents CMV-induced chronic graft dysfunction

Ganciclovir, which is used to treat cytomegalovirus (CMV) infection, has been shown in rodent models to abolish CMV-mediated chronic cellular damage and endothelial cell proliferation; when associated with mycophenolate mofetil (MMF), it has been shown to increase its anti-herpes virus activity. This study tested the hypothesis that kidney graft recipients who received antirejection prophylaxis with MMF and who were treated with ganciclovir for a declared CMV disease could be protected from chronic graft dysfunction. Investigated was the impact of ganciclovir-treated CMV diseases in consecutive first kidney recipients according to their immunosuppressive therapy. The azathioprine (Aza)-treated group (Aza group) included 319 patients. The MMF-treated group (MMF group) included 126 patients. CMV disease was clinically defined and confirmed by virological proof of CMV infection and was treated for at least 14 d with ganciclovir. Despite having the same incidence (21.6% in the Aza group versus 24.6% in the MMF group) and severity, CMV disease was significantly associated with graft loss independent of acute rejection episodes or other factors when tested in a Cox proportional model in the Aza group only (P < 10(-4)). It was shown for the first time that patients whose CMV disease is treated with ganciclovir while they are on MMF therapy are protected from the long-term deleterious consequences of CMV disease on graft survival, independent of acute rejection. It is suggested that the enhanced anti-herpes virus activity of ganciclovir by MMF could contribute to this reported effect, which may represent a significant contribution of MMF efficacy to graft survival.

Immunologic Aspects of Transplant Management: Pharmacotherapy and Rejection

The intensivist caring for the critically ill transplant patient must be knowledgeable in the management of immunosuppression or have expert help. Critical illness often has a major impact on the absorption and metabolism of immunosuppressive drugs, increasing or decreasing net immunosuppression. Too little immunosuppression brings the risk of graft loss, while too much increases the morbidity and mortality of serious infection. Optimum management often requires the skillful manipulation of dosage and/or routes of drug delivery. In many cases of life-threatening infection, immunosuppression must be discontinued altogether and restarted prior to significant graft injury. The cost of miscalculation is very high. Loss of a renal, pancreas, or small bowel transplant is tragic, while loss of a heart, lung, or liver is usually fatal. Unfortunately the management of immunosuppression is becoming more complex. As the field of transplantation matures, new immunosuppressants are being introduced. Also, more experience and growing numbers of clinical trials are making the required knowledge base ever larger. Each type of transplant has its own set of evolving immunosuppression strategies. This review presents the basic mechanisms of the most widely used drugs and the dangers of immunosuppression. The drugs are then discussed in the context of liver, small bowel, kidney, pancreas, heart, and lung transplantation. Finally, a brief section on the practical pharmacokinetics of the drugs is presented.

Low incidence of kidney rejection after simultaneous kidney-pancreas transplantation after antithymocyte globulin induction and in the absence of corticosteroids: results of a prospective pilot study in 28 consecutive cases

BACKGROUND

Recipients of simultaneous kidney-pancreas transplantation receive a combination of polyclonal antithymocyte globulin (ATG), cyclosporin or tacrolimus, mycophenolate mofetil (MMF) and corticosteroids (Cs). To avoid the side effects and adverse events associated with Cs, we investigated a new immunosuppressive regimen without Cs after simultaneous kidney-pancreas transplantation.

METHODS

A total of 28 consecutive patients who underwent simultaneous kidney-pancreas transplantation were included in this study. All patients received ATG, cyclosporin, and MMF.

RESULTS

All patients but one tolerated the ATG course well. MMF was definitively discontinued in three patients because of leukopenia. Cytomegalovirus infection was diagnosed in eight patients (28.5%). Only two patients (7%) required an antirejection treatment. Patient, kidney, and pancreas survival is currently 96.4, 96.4, and 75%, respectively.

CONCLUSIONS

The combination of ATG, cyclosporin, and MMF, without Cs, was well tolerated. The unexpectedly low (7%) incidence of acute kidney rejection observed suggests that Cs may partially interfere with the immunosuppressive effect of ATG.