Treatment of a patient with myasthenia gravis using antibodies against CD25

OBJECTIVES

To measure clinical and immunological parameters in a patient with myasthenia gravis (MG) treated with antibodies against CD25 (basiliximab, Simulect). Patient and methods - Injections of basiliximab were given repeatedly together with cyclosporin A and corticosteroids for 9 months to a patient with severe MG. Her muscle function score was monitored and the immunological parameters were followed using ELISA, flow cytometry and radioimmunoassay.

RESULTS

The patient improved moderately and corticosteroid treatment could be withdrawn. The percentage of activated CD4+ T cells decreased during treatment, while that of 'naïve' T cells increased. The serum levels of sCD28, sCD152, sCD80, sCD86 and IL-10 decreased. The treatment was stopped due to repeated infections.

CONCLUSION

Treatment with basiliximab appears to be suitable only for severely ill patients who do not respond to conventional treatments. However, careful monitoring of side effects is necessary.

Basiliximab vs. limited-dose daclizumab (2 mg/kg) administered in single or two separated doses in kidney transplantation

INTRODUCTION

Addition of anti-IL2r monoclonal antibodies (chimeric or humanized) for induction therapy has reduced the frequency of acute rejection (AR). This study compares the impact of type and dosage of induction therapy on frequency of acute rejection and on renal function during the first year post-transplant.

PATIENTS AND METHODS

Comparative retrospective study. Kidney transplant recipients (KTR) were divided in three groups according to induction therapy, as follows: (1) Basiliximab in two 20 mg doses, (2) Daclizumab 2 mg/kg in one dose, and (3) Daclizumab 2 mg/kg divided in two doses (1 mg/kg each). Groups were paired for age, sex, number of shared haplotypes, and previous transplant history. Primary endpoints were AR episodes, time to first AR, graft loss, and death. Secondary endpoints were SCr (at 3, 6, 9 and 12 months), frequency and type of infection, and cost.

RESULTS

There were no baseline differences between groups. Twenty one patients were included in each group. The incidence of AR was similar: 14.2% in group 1, and 9.5% for groups 2 and 3. Two deaths were reported, one in group 1 and another in group 2. Mean SCr was similar between groups. Incidence of infection was 6, 5, and 7 in groups 1 to 3, respectively without a significant difference. The cost was higher in group 1 (p < 0.001).

CONCLUSION

Low dose Daclizumab in one or two doses is equally effective and safe as basiliximab at 12-month follow-up, with inferior cost.

Biliary complications after duct-to-duct biliary reconstruction in living-donor liver transplantation: causes and treatment

BACKGROUND

In living-donor liver transplantation (LDLT), biliary complications are recognized as a significant cause of post-transplantation morbidity.

METHODS

Eighty patients who underwent LDLT with duct-to-duct biliary reconstruction at Hiroshima University Hospital were enrolled in this study. The mean follow-up was 24 months (range, 3-72 months). Eighteen patients underwent the basiliximab-based immunosuppressive therapy, and 62 patients underwent non-basiliximab-based immunosuppressive therapy. The development of biliary complications after LDLT was retrospectively analyzed. Biliary complications were initially treated by endoscopic or radiological modalities.

RESULTS

Biliary leakages and strictures occurred in 12 (15%) and 20 (25%) of the 80 patients, respectively. Stepwise multivariate analysis demonstrated bile leakage to be an independent risk factor for the development of biliary stricture (p = 0.001) and basiliximab-based immunosuppressive therapy to be an independent protective factor for postoperative biliary leakage (p = 0.005). The 1-week total doses of steroids were significantly lower in the basiliximab-based immunosuppressive regimes (mean dose: 573 mg) than in the non-basiliximab-based ones (mean dose: 1,121 mg) (p = 0.01). All patients with biliary leakage were successfully treated with endoscopic or radiological modalities, except one patient who was treated by surgical treatment. Endoscopic or radiological modalities were successful as primary treatment modalities in 12 (60%) of 20 patients with biliary strictures. Lastly, six patients were treated surgically with long-term success, except for one patient with chronic cholangitis who died after 16 months.

CONCLUSIONS

Steroid-sparing basiliximab-based immunosuppressive therapy reduced the incidence of biliary leakage, and biliary leakage was the independent factor for biliary stricture. The non-surgical and surgical treatments for biliary complications were satisfactory.

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.

Steroid-avoidance immunosuppression regimen in live-donor renal allotransplant recipients: a prospective, randomized, controlled study

OBJECTIVES

Steroids have occupied a major role in renal transplantation for more than 4 decades. However, chronic use of steroids is associated with numerous comorbidities. We sought to elucidate the safety and efficacy of a steroid-free immunosuppression regimen in live-donor renal transplant recipients.

PATIENTS AND METHODS

One hundred patients were randomized to receive tacrolimus, mycophenolate mofetil, basiliximab induction, and steroids only for 3 days (experimental group, n=50 patients) or tacrolimus, mycophenolate mofetil, basiliximab induction, and steroid maintenance (control group, n=50 patients,). The median follow-up was 12 months.

RESULTS

Patient and graft survival rates were 100% in both groups. The rate of biopsy-proven acute rejection was 16% in both groups. For patients in the control group, the mean serum creatinine level was 111.22 micromol /L compared with 110.39 micromol/L in patients in the experimental group. Posttransplant hypertension was encountered in 4% of the patients in the experimental group compared with 24% of the patients in the control group (P = .0009). Posttransplant diabetes mellitus was detected in 4% of the patients in the experimental group compared with 16% of the patients in the control group (P = .037). Posttransplant weight gain was reported in 6% of the patients in the experimental group compared with 15% of the patients in the control group (P = .001). The chronic allograft damage indexes of biopsy specimens at 1-year follow-up were comparable in both groups (2.48 vs 2.28, respectively) (P = .16).

CONCLUSIONS

In living-donor renal transplant recipients with low immunologic risk, steroid avoidance (using basiliximab induction, tacrolimus, mycophenolate mofetil maintenance, and 3 days' steroid treatment) is feasible, safe, and carries with it fewer morbidities compared with the same immunosuppressive protocol with steroid maintenance. Longer follow-ups are required to prove the safety of this regimen.

Early steroid withdrawal in pediatric renal transplant on newer immunosuppressive drugs

Steroids have been a cornerstone in renal transplant immunosuppression. New immunosuppressive drugs have led to protocols using early steroid withdrawal or complete avoidance. A prospective protocol in 23 pediatric renal transplant (ages 2-14 yr) who received decreasing steroid doses stopping at day 7 post-Tx, FK, and MMF were compared with a CsA, AZT, historically matched steroid-based control group. Basiliximab was used in two doses. Anthropometric, biochemical variables, AR rates, and CMV infection were evaluated and compared using Student's t-test and regression analysis. A better growth pattern was seen in steroid withdrawal group. GFR rate and serum glucose were similar in both groups. Total serum cholesterol levels were significantly lower in steroid withdrawal group. The incidence of AR at 12 months was 4.3% in steroid withdrawal group vs. 8.6% in steroid-based group (p = ns). No difference in CMV infection was observed. Hemoglobin levels were low during the first months in both groups; reached normal values after six months. SBP became higher at 12 months in steroid-based group. Patient and graft survival was 98% in both groups at one-yr post-transplant. Early steroid withdrawal was efficacious, safe, and did not increase risk of rejection, preserving optimal growth, renal function, and reducing cardiovascular risk factors.

Individualized mycophenolate mofetil dosing based on drug exposure significantly improves patient outcomes after renal transplantation

Efficacy and safety of mycophenolate mofetil (MMF) may be optimized with individualized doses based on therapeutic monitoring of its active metabolite, mycophenolic acid (MPA). In this 12-month study, 137 renal allograft recipients from 11 French centers receiving basiliximab, cyclosporine A, MMF and corticosteroids were randomized to receive either concentration-controlled doses or fixed-dose MMF. A novel Bayesian estimator of MPA AUC based on three-point sampling was used to individualize doses on posttransplant days 7 and 14 and months 1, 3 and 6. The primary endpoint was treatment failure (death, graft loss, acute rejection and MMF discontinuation). Data from 65 patients/group were analyzed. At month 12, the concentration-controlled group had fewer treatment failures (p = 0.03) and acute rejection episodes (p = 0.01) with no differences in adverse event frequency. The MMF dose was higher in the concentration-controlled group at day 14 (p < 0.0001), month 1 (p < 0.0001) and month 3 (p < 0.01), as were median AUCs on day 14 (33.7 vs. 27.1 mg*h/L; p = 0.0001) and at month 1 (45.0 vs. 30.9 mg*h/L; p < 0.0001). Therapeutic MPA monitoring using a limited sampling strategy can reduce the risk of treatment failure and acute rejection in renal allograft recipients 12 months posttransplant with no increase in adverse events.

Steroid minimization in liver transplant recipients: impact on hepatitis C recurrence and post-transplant diabetes

BACKGROUND

Steroid minimization regimens have become increasingly popular for kidney transplant recipients. We studied outcomes for liver transplant recipients with a regimen using rapid discontinuation of prednisone (RDP).

RESULTS

The study group consisted of 83 recipients transplanted between June 2004 and January 2006. Immunosuppression consisted of tacrolimus, MMF, and two doses of basiliximab with six d of steroids. Patients with underlying autoimmune disorders (PSC, autoimmune hepatitis) were not included as they were maintained on steroids. The control group consisted of 83 recipients transplanted between January 2002 and May 2004. Immunosuppression consisted of tacrolimus, MMF and steroids, with no antibody induction. Mean MELD score at time of transplant was significantly higher in the steroid free group vs. the control group (28 vs. 23, p = 0.02); mean donor age was also higher (42 vs. 37 yr, p = 0.02). Other characteristics including recipient age, cold ischemic time, donor source, and cause of liver disease were similar (p = ns). Mean length of follow-up was 16.1 months in the RDP group and 32 months in the control group; a minimum of six months follow up was present for all patients. Patient and graft survival rates were not statistically different in the two groups (p = ns). Biopsy proven rejection was low in both groups and not significantly different (at one yr post-transplant 11% in the RDP group vs. 12% in control, p = 0.53). Based on protocol biopsy data, histologic recurrence of hepatitis C was demonstrated in 56% of the control group hepatitis C positive recipients vs. 39% in the RDP group (p = 0.05). There was a significantly lower incidence of post-transplant diabetes (PTDM) in the RDP vs. control group (at 6 months post-transplant 12% vs. 32%, p = 0.004).

CONCLUSIONS

Rapid discontinuation of prednisone in liver transplant recipients is not associated with an increased risk of rejection, and may be associated with lower morbidity, especially PTDM and hepatitis C recurrence.

Sequential quadruple immunosuppression including sirolimus in extended criteria and nonheartbeating donor kidney transplantation

The aim was to evaluate feasibility and safety of calcineurin inhibitor-free immunosuppression in high-risk donor kidney transplantation with sequential sirolimus introduction. Kidney transplant patients (n=76) with a donor aged >60 years, donor with acute renal failure, or a nonheartbeating donor were included. Immunosuppression consisted of antithymocyte globulin or basiliximab, mycophenolate mofetil, prednisone, and sequential introduction of sirolimus. One-year patient survival was 96.2% and 95.8%; graft survival was 94.2% and 91.7%; acute rejection rates were 21.2% and 12.4%; delayed graft function was 21.2% and 66.7%; and creatinine clearance was 58+/-20 mL/min and 56+/-21 mL/min for the brain-dead donor group and the nonheartbeating donor group, respectively. Most adverse events were infections, but also three lymphoceles, three urinary fistulas, three wound seromas. Sequential sirolimus introduction in high-risk donor kidney transplantation was found to lead to good patient and graft survival and incidence of acute rejection and delayed graft function.

Do Anti-CD25 Monoclonal Antibodies Potentiate Posttransplant Diabetes Mellitus?

Anti-CD25 monoclonal antibodies (MAbs) are directed against the IL-2 (CD-25) receptor, which is associated with the pathogenesis of diabetes mellitus (DM). Measuring CD25 on peripheral blood lymphocytes could be a new immunologic marker to identify patients with prediabetes.

OBJECTIVE

The study aimed to analyze whether administration of anti-CD25 MAbs was an independent risk factor for posttransplant diabetes mellitus (PTDM) in kidney transplant (KT) patients at 3 months after transplantation.

PATIENTS AND METHODS

Seventy-four stable, nondiabetic KT patients were included in the study. The overall sex distribution was 70% men and mean overall age, 52 +/- 10 years. Thirty-eight subjects where treated with anti-CD25 antibodies (basiliximab). The diagnosis of PTDM was made if patients required insulin or oral antidiabetic drugs and/or had glycemia >200 mg/dL at 120 minutes after an oral glucose tolerance test (75 g glucose). We determined the age, weight, body mass index, acute rejection, chronic hepatitis C virus (HCV) infection, and type of calcineurin inhibitor.

RESULTS

Thirty-four percent of patients developed PTDM. Patients treated with anti-CD25 antibodies were older (P = .022) and showed a greater incidence of PTDM (P = .041). The logistic regression analysis (dependent variable: PTDM; independent variables: age, anti-CD25, tacrolimus vs cyclosporine) showed that treatment with anti-CD25 is an independent risk factor for PTDM (P = .041; OR 3.28; CI 95% 1.04-10.31).

CONCLUSION

Patients treated with anti-CD25 MAbs showed greater incidence of PTDM.

Single bolus antithymocyte globulin versus basiliximab induction in kidney transplantation with cyclosporine triple immunosuppression: efficacy and safety

BACKGROUND

The aim of this prospective randomized study was to examine the effect of induction immunosuppression and low initial cyclosporine (CsA) on the onset of graft function and its long-term consequences.

METHODS

During 1999-2001, 155 patients were randomized to single 9 mg/kg dose antithymocyte globulin (ATG)-Fresenius (group A) or two 20-mg doses of basiliximab (group B) with reduced dose CsA or conventional CsA triple therapy without induction (group C).

RESULTS

Delayed function (DGF) was lower in group A than in groups B or C (5.7% vs. 24.1% and 15.9%, P<0.025) and need of dialysis was less in groups A and B compared to C (10.3 and 10.4 vs. 20.0 days, P<0.05). Acute rejections occurred in 11.3%, 12.1% and 20.5%, and the mean (median) time to rejection was 16 (13), 97 (46) and 101 (35) days in groups A, B, and C, respectively (P<0.005). One-and 5-year graft survivals (GS) were 98.1% and 90.6% (group A), 96.6% and 96.6% (group B), and 93.2% and 84.1% (group C). Five-year GS was significantly better in group B than in group C (P<0.05). The death censored 5-year GS in groups A, B, and C were 94.3%, 96.6%, and 90.0% (P=NS). Single high-dose ATG induction was associated with hemodynamic and pulmonary disturbances without, however, serious or long-term consequences.

CONCLUSIONS

ATG induction significantly reduced DGF. Both induction regimens together with low initial CsA led to significantly less posttransplant dialysis and excellent survival. The high dose ATG was associated with significant hemodynamic and pulmonary side effects during drug infusion.

Conversion from a calcineurin inhibitor-based immunosuppressive regimen to everolimus in renal transplant recipients: effect on renal function and proteinuria

New immunosuppressive agents are being actively researched to avoid complications of chronic allograft nephropathy (CAN), calcineurin inhibitor (CNI) nephrotoxicity, and posttransplantation cancer. The family of mTOR inhibitors offers a unique immunosuppressive opportunity to avoid CNI toxicity and reduce the incidence of malignancy. Nevertheless, increasing data have demonstrated that sirolimus (SRL), the first mTOR introduced in the treatment of solid organ transplant recipients, induces proteinuria, an adverse event that could produce deterioration of long-term renal function. In this short-term study of patients followed for 1 to 16 months, we examined changes in renal function and proteinuria among renal transplant recipients converted from a CNI-based regimen to an everolimus (EVL)-based one, a recently introduced mTOR inhibitor. Our data showed that renal function can be optimized after conversion to EVL by up to 42% in recipients showing CAN grade 1 or 2, or CNI nephrotoxicity. Importantly, patients who improved their creatinine clearance did not show increased proteinuria measured in a voided specimen as the ratio of urinary protein and creatinine concentration (P/C). These results, if confirmed with long-term follow-up and a larger number of patients, would allow us to consider EVL as a promising agent for maintenance immunosuppressive regimens in kidney transplantation.

Basiliximab and heart transplantation in Hispanics: the experience in Puerto Rico

BACKGROUND

Induction immunotherapy in addition to standard triple therapy at the time of cardiac transplantation with cytolytic antibodies has been used in recipients with pre transplant renal impairment, and to prevent rejection. Recently, anti-interlukin-2 receptor monoclonal antibodies have been used for these purposes. A retrospective study of 58 heart transplant recipients was conducted to assess the effect of basiliximab, a chimeric anti-interlukin-2 receptor monoclonal antibody on biopsy proven acute rejection, serum creatinine, creatinine clearance, hospitalizations due to infection and mortality one year after transplantation.

METHODS

A total of 58 heart transplant patient's charts were reviewed. All patients received triple immunosuppressive therapy with cyclosporine or tacrolimus, mycophenolate mofetil and prednisone post transplant. Basiliximab 20 mg on day 0 and day 4 was administered as induction therapy in a subgroup of patients. Both groups had similar pre transplant characteristics. Analysis was performed at intervals of 0-17 weeks, 18-34 weeks, 35-52 weeks, and one year overall. The incidence of acute rejection episodes, post-transplant renal function, patient survival and hospitalizations due to infection was analyzed.

RESULTS

Twenty-seven patients received induction therapy with basiliximab and 31 patients did not. Basiliximab induction helped reduce acute rejection overall during the first year, with 22 episodes of rejection in the induction group, and 67 episodes in the no induction group. In the 0-17 weeks following transplantation there were 20 reported rejection episodes in the induction group versus 58 rejection episodes in the no-induction group, demonstrating also reduction of rejection by induction in this group. Basiliximab induction group had preserved renal function, with higher creatinine clearance at 1 year when compared to the no induction group. There were no differences between groups in terms of hospitalizations due to infections or mortality.

CONCLUSION

Induction therapy with basiliximab significantly reduced the number of acute rejection within the first year after heart transplantation, without a negative impact on patient's renal function, risk of infection or mortality.

Lower Risk of Infectious Deaths in Cardiac Transplant Patients Receiving Basiliximab Versus Anti-thymocyte Globulin as Induction Therapy

BACKGROUND

Conventional antibody induction therapy is currently used in heart transplantation despite safety concerns. This 6-month, prospective, randomized, multicenter, open-label study examined whether basiliximab offers a tolerability benefit compared with anti-thymocyte globulin (ATG) while maintaining similar efficacy in de novo heart transplant recipients.

METHODS

Adult heart transplant recipients were randomized to receive basiliximab (20 mg on Day 0 and Day 4) or ATG (2.5 mg/kg/day for 3 to 5 days) with cyclosporine, mycophenolate mofetil and steroids. The primary safety end-point was a composite of serum sickness, fever, cutaneous rash, anaphylaxis, infection, thrombocytopenia, leukopenia and post-transplant proliferative disease. Efficacy was assessed by a composite end-point of death, graft loss, acute rejection Grade > 1B, acute rejection associated with hemodynamic compromise or treated with antibody therapy, or loss to follow-up, whichever occurred first.

RESULTS

Eighty patients were randomized and analyzed. By Month 6, the incidence of the composite safety end-point was significantly lower with basiliximab than with ATG (50.0% vs 78.6%, p = 0.01), and infectious death was less frequent in the basiliximab group (0 of 38 vs 6 of 42, p = 0.027). The composite efficacy end-point occurred in 24 patients (63.2%) in the basiliximab arm vs 28 patients (66.7%, p = not significant [NS]) receiving ATG. Acute rejection episodes of Grade > or = 1B were reported with similar frequency (50% with basiliximab vs 45.2% with ATG, p = NS); 7 patients (18.4%) in the basiliximab group and 3 (7.1%) in the ATG group had rejection Grade > or = 3A.

CONCLUSIONS

These results suggest that basiliximab offers improved tolerability with similar efficacy compared with current polyclonal antibody induction therapy in de novo heart transplant patients.

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.

Renal function with cyclosporine C2 monitoring, enteric-coated mycophenolate sodium and basiliximab: a 12-month randomized trial in renal transplant recipients

BACKGROUND

Cyclosporine exposure, as estimated by the area under the curve (AUC), predicts outcomes in renal transplantation. Cyclosporine concentration at two h post-dose (C(2)) has been shown to be the most reliable, single-point surrogate marker for AUC. The objective of this study was to measure renal function beyond month 2 post-transplant using two different C(2) maintenance targets in combination with enteric-coated mycophenolate sodium (EC-MPS), corticosteroids, and basiliximab induction.

METHODS

In this open-label, multicenter trial, renal transplant recipients entered one of two randomized groups at day 61 post-transplant: group A (higher-C(2) range) or group B (lower-C(2) range).

RESULTS

Patients (164) were recruited, and 141 patients were entered the randomized groups (group A, n = 66; group B, n = 75). At 12 months, the mean calculated creatinine clearance was significantly greater in group B than in group A (79.2 vs. 71.0 mL/min, p < 0.05). Biopsy-proven acute rejection occurred in 14.7% patients in group B and in 24.2% patients in group A (n.s.). During the 12-month trial, 17.7% patients discontinued EC-MPS because of adverse events. Group B (44.0%) had fewer serious adverse events when compared with group A (62.1%; p = 0.04). Overall patient and graft survival were 99.4% and 95.7% respectively. Among 99 high-risk patients (i.e., African-American race, previous transplant, PRA >35% or >4 HLA mismatches), mean creatinine clearance at 12 months was 65.6 mL/min and biopsy-proven rejection occurred in 20.2% patients.

CONCLUSIONS

Low cyclosporine C(2) levels are associated with improved renal function compared with higher C(2) levels when used in conjunction with EC-MPS, steroids and basiliximab induction. EC-MPS with low cyclosporine C(2) levels, corticosteroids and basiliximab provides excellent renal function with good efficacy even in high-risk patients.

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

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

Reduced-exposure cyclosporine is safe and efficacious in de novo renal transplant recipients treated with enteric-coated mycophenolic acid and basiliximab

BACKGROUND

The lower limit of exposure to calcineurin inhibitors has not yet been established in de novo renal transplant patients receiving mycophenolic acid therapy with basiliximab.

METHODS

A 12-month, multicenter, randomized, open-label trial was carried out in which de novo renal transplant patients received enteric-coated mycophenolate sodium, cyclosporine microemulsion, steroids and basiliximab. Patients were randomized to receive standard-exposure (n = 45) or reduced-exposure (n = 44) cyclosporine, based on differing C2 target ranges, after the first month post-transplant.

RESULTS

Cyclosporine exposure gradually increased over the first month and was lower than previously recommended. Mean calculated creatinine clearance (primary end-point) was similar in the standard-exposure and reduced-exposure groups at month 6 (55.3+/-3.2 ml/min and 61.5+/-3.7 ml/min respectively, n.s.). There were 4 deaths but no death-censored graft losses, resulting in 95.5% patient and graft survival at one year in both groups. At 6 and 12 months, the incidence of biopsy-proven acute rejection was 17.8% and 17.8% in the standard-exposure group, and 13.6% and 15.9% in the reduced-exposure group. Adverse events were similar between treatment groups. Exploratory analyses could not identify a lower limit for the optimal CsA exposure range, but results suggested that high exposure at one year was associated with deteriorating renal function.

CONCLUSIONS

These results indicate that enteric-coated mycophenolate sodium with reduced-exposure cyclosporine, steroids and basiliximab induction has an excellent therapeutic effect and is safe in de novo kidney transplant recipients. Lower C2 targets than previously recommended, particularly early post-transplant, do not appear to be associated with compromised efficacy.

Identification of Their Epitope Reveals the Structural Basis for the Mechanism of Action of the Immunosuppressive Antibodies Basiliximab and Daclizumab

Interleukin-2 (IL-2) and its receptor (IL-2R) play a major role in cellular immunity. The monoclonal antibodies basiliximab and daclizumab directed against the IL-2R subunit CD25 are widely used to prevent graft or host rejection after allogeneic tissue transplantation. Although these antibodies have been used for this purpose for many years, their common epitope within the CD25 protein is unknown. We screened a random phage display library to isolate peptides specifically binding to basiliximab. A striking amino acid sequence motif was enriched. This motif is homologous to the peptide ERIYHFV comprising amino acid positions 116 to 122 within the extracellular domain of CD25, suggesting that this is the basiliximab epitope. Basiliximab and daclizumab binding of selected phage was specific, as no binding was observed to isotype antibody controls. Phage binding could be inhibited by the cognate peptide. In cells expressing mutant CD25, binding of basiliximab was abolished when two or more amino acids of the suspected epitope were changed. In contrast, basiliximab binding remained unaffected in cells expressing CD25 versions with mutations outside this epitope. We therefore conclude that the (116)ERIYHFV(122) string within CD25 is the epitope recognized by basiliximab and daclizumab. This epitope overlaps with the interaction site of CD25 and IL-2, thus revealing the structural basis for the inhibition of IL-2R binding by this class of immunosuppressive antibodies.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Report of the Experience With Enteric-Coated Sodium Mycophenolate in a De Novo Population of Kidney Transplant Recipients at High Risk for Delayed Graft Function

The introduction of mycophenolate as an adjuvant in immunosuppressive regimes has improved clinical outcomes of transplant patients due to a reduced incidence of acute rejection episodes. Nevertheless, the need for dose adjustments or therapy discontinuations (up to 45% in some series), have downgraded the efficacy of mycophenolate mofetil (MMF). From October 2003 to April 2005, 36 kidney transplantations were performed at our site. The immunosuppressive protocol included induction with basiliximab, administered on days 0 and 4 posttransplantation, cyclosporine microemulsion (CsA-ME) monitored by concentrations at 2 hours (C2), enteric-coated sodium mycophenolate (EC-MPS; 720 +/- 180 mg bid), and steroids. Mean follow-up time was 7.3 +/- 4.4 months. Fourteen patients (38.9%) experienced delayed graft function (DGF). Seven (19%) episodes of acute rejection included 5 graded as I-A, 1 as grade I-B, and 1 as grade II-A. There were discontinuations of EC-MPS. Regarding gastrointestinal (GI) adverse events, there were 2 episodes of noninfectious diarrhea, 1 gastritis, and 1 upper GI hemorrhage. There were 11 infections: 4 in the urinary tract; 3 in the lung; 3 in the GI tract; and 1 CMV infection. There were no discontinuations of EC-MPS reported [corrected] Two (6%) graft losses were reported to be due to sepsis. In this group of patients who experienced a high incidence of DGF, the combination of basiliximab, CsA-ME (monitored by C2), and EC-MPS resulted in low Banff grade acute rejection episodes which were all responsive to steroids. The incidence of GI adverse events was only 11%.

Basiliximab Improves Graft Survival in Renal Transplant Recipients With Delayed Graft Function

The aim of this study was to evaluate the use of basiliximab in first renal transplant recipients with delayed graft function, defined by the need for dialysis in the first week posttransplantation. Among 148 patients in the study, 90 received basiliximab (60.8%) with 58 comprising the control group. There were no significant differences between the 2 groups related to the evaluated variables, except that the control group received more blood transfusions pretransplantation. There was a lower incidence of steroid-resistant rejection (6% vs 20.9%; P = .017) and humoral rejections (0% vs 7%; P = .038) in the basiliximab group. Also, graft survival was significantly higher in basiliximab group compared with the control one (92.8% vs 80.4%; P = .028). There were no significant differences in the other outcomes. In conclusion, this study confirmed the beneficial effects of addition of basiliximab to the immunosuppressive schema of patients with delayed graft function.

Basiliximab and Rabbit Anti-thymocyte Globulin for Prophylaxis of Acute Rejection After Heart Transplantation: A Non-inferiority Trial

BACKGROUND

Induction of immunosuppression with antibodies after heart transplantation decreases early acute rejection rate compared with placebo. We tested the non-inferiority of basiliximab vs rabbit anti-thymocyte globulin (RATG) on the incidence of acute rejection 6 months after transplantation.

METHODS

From July 2002 to April 2004, 35 patients were enrolled in a multicenter, parallel group, open-label, non-inferiority trial. Patients were randomized to receive induction treatment with basiliximab (20 mg on Day 0 and 4) or RATG (125 mg on Day 0, 1, and 2). Standard maintenance therapy with cyclosporine, mycophenolate mofetil, and prednisone was used.

RESULTS

Seventeen patients (aged 54 +/- 9 years old) received basiliximab, and 18 patients (aged 54 +/- 12 years old) received RATG. The freedom rate of rejection at 6 months (grade 3A or more) averaged 65% (11/17) with basiliximab and 83% (15/18) with RATG. The upper limit of the 1-sided 90% confidence interval for the difference RATG-basiliximab was 37.2%, exceeding the 22.5% non-inferiority margin. CD3 and CD4 levels were higher (p < 0.0001 for both), whereas CD25/CD4 and CD25/CD8 levels were lower (p < 0.0001 and p = 0.0462, respectively) in patients treated with basiliximab. One of the 14 basiliximab patients showed detectable cytomegalovirus viral load during the first 3 months after transplantation, whereas cytomegalovirus was detected by quantitative polymerase chain reaction in the plasma of 5 of the 13 RATG patients (p = 0.0505).

CONCLUSION

Non-inferiority of basiliximab treatment for prophylaxis of acute rejection after heart transplantation could not be shown. RATG administration is associated with a higher rate of asymptomatic cytomegalovirus viral load detection in the plasma.

[Early steroid withdrawal in pediatric renal transplantation]

BACKGROUND

Cardiovascular risk, growth failure and the new immunosuppressive drugs, have encouraged steroid withdrawal or total avoidance with promising results in renal transplant (Tx) immunosuppression.

AIM

To evaluate a new immunosuppressor protocol with early withdrawal of steroids in pediatric kidney transplant.

PATIENTS AND METHODS

Prospective study in pediatric patients older than 1 year and low immunological risk. Group A (n =28): steroids in decreasing doses until day 7 post Tx, tacrolimus (FK) and mycophenolate mofetil (MMF). Group B (n =28) control: steroids, cyclosporine and azathioprine or steroids, FK and MMF. In both groups the induction therapy included basiliximab. Anthropometric and biochemical variables (renal function, lipid profile, hematological, blood glucose and acid-base equilibrium), acute rejection and CMV infection, were evaluated. Mean values and variations for continuous variables were calculated at months 1, 6, 12 and 18.

RESULTS

Two children were withdrawn before month 2, one had an untreatable diarrhea and the second died due to Aspergillus septicemia. Mean values at months 1, 6, 12 and 18 for groups A and B: Creatinine clearance (ml/min): 85.4 vs 89; 79.9 vs 83; 89 vs 80; 79.8 vs 80.6 (p: ns); hematocrit (%): 28.8 vs 30.4; 31.7 vs 34.4; 34.4; 32.4 vs 34.8; 34.4 vs 35.5 (p: ns). Total cholesterol (mg/dl): 151 vs 206; 139 vs 174; 138 vs 186; 140 vs 180 (p <0.05). Mean delta height/age Z score at the first year: 0.5 vs 0.15; 0.7 vs 0.22; 0.97 vs 0.25 (p <0.05). Mean systolic blood pressure Z score: 0.9 vs 1.5; 0.5 vs 0.9; -0.3 vs 0.8; 0.1 vs 1.0 (p <0.05). The height/age Z score was significantly superior in patients without steroids. A normalization of growth patterns at month 18 was observed (< 0.05). Both groups presented a negative variation of creatinine clearance during the follow-up, but it was minor in the study group (p <0.05). Two acute rejections were found in each group, and no difference in CMV infections was observed.

CONCLUSIONS

Early steroid withdrawal in pediatric renal transplant recipients was effective and safe and did not increase the risk of rejection.