Alberto Zarak

Randomized Trial of Immunosuppressive Regimens in Renal Transplantation

The optimal long-term regimen for immunosuppression for kidney transplant recipients is unknown. We conducted a randomized trial involving 150 kidney transplant recipients to compare tacrolimus/sirolimus, tacrolimus/mycophenolate mofetil (MMF), and cyclosporine/sirolimus. All patients received daclizumab induction and maintenance corticosteroids. Median follow-up was 8 yr post-transplant. Acute rejection (AR) occurred significantly less often among those treated with tacrolimus/MMF (12%) than among those treated with tacrolimus/sirolimus (30%) or cyclosporine/sirolimus (28%). Mean estimated GFR was consistently higher in the tacrolimus/MMF arm, especially after controlling for donor age in a multivariable model during the first 36 mo (P ≤ 0.008). The rate of dying with a functioning graft was significantly higher among those treated with tacrolimus/sirolimus (26%) than among those treated with tacrolimus/MMF (12%) or cyclosporine/sirolimus (4%). We did not observe significant differences in actuarial graft survival at 8 yr post-transplant between the groups. Patient noncompliance seemed responsible for 45% (13/29) of observed graft failures, with 11 of these occurring after 36 mo. Significantly more viral infections, protocol violations, and need for antilipid therapy occurred among patients receiving sirolimus, but we did not observe differences between the groups with regard to infections requiring hospitalization or new-onset diabetes. Taken together, these results suggest that maintenance therapy with tacrolimus/MMF is more favorable than either tacrolimus/sirolimus or cyclosporine/sirolimus.

Randomized trial of thymoglobulin versus alemtuzumab (with lower dose maintenance immunosuppression) versus daclizumab in living donor renal transplantation

BACKGROUND We performed a randomized trial evaluating alemtuzumab, a humanized anti-CD52 monoclonal antibody, in living donor (LD) kidney transplantation. METHODS Thirty-eight LD first renal transplant recipients were randomized into three single-agent antibody induction groups: thymoglobulin (group A); alemtuzumab (group B); and daclizumab (group C). In groups A and C, target tacrolimus trough levels were 6 to 8 ng/mL, with 1 gm mycophenolate mofetil (MMF) administered twice daily, and maintenance methylprednisolone. In group B, the target tacrolimus trough level was 4 to 6 ng/mL, with 500 mg MMF administered twice daily, without methylprednisolone. RESULTS With 29/38 patients now followed beyond 36 months posttransplantation, we observed no graft failures and only one death with a functioning graft (in group B). Acute rejection episodes were low: 0/13, 1/13, and 1/12 patients in groups A, B, and C. Biopsy-proven chronic allograft injury was higher among group B (3/13) versus groups A (0/13) or C (0/12; P = .01). Poorer renal function was observed in group B; the mean calculated creatinine clearance at 3 months posttransplantation was significantly poorer: 63.3 ± 3.0 versus 85.4 ± 7.2 and 82.2 ± 8.2 in groups A and C (P = .01). No differences in the incidence of adverse events were observed.

Favorable outcomes with machine perfusion and longer pump times in kidney transplantation: a single-center, observational study.

Background. Hypothermic machine perfusion (MP) preservation is used for all deceased donor kidney transplants at our center. Kidneys are placed in cold storage at retrieval, then transferred to MP on arrival. Because a lack of consensus regarding optimal use of MP still exists, we evaluated the overall impact of using MP at our center and the prognostic value of MP (Pump) time. Methods. We retrospectively analyzed 339 adult, primary deceased donor kidney transplant recipients who were pooled across three prospective, randomized immunosuppression trials (since 2000) at our center. In addition to providing overall results for delayed graft function (DGF) (requirement for dialysis in the first week), slow graft function (SGF), first biopsy-proven acute rejection (BPAR), and graft failure, stepwise logistic and Cox regression analyses were used to determine the prognostic value of pump time, particularly after controlling for other significant prognosticators. Results. Mean cold storage and pump times were 6.6 and 26.7 hr, consistent across immunosuppression protocols. Overall DGF and SGF rates were 4.4% (15/339) and 12.1% (41/339). DGF was equally low for pump time less than 24 vs. more than or equal to 24 hr, 5.2% (6/116) vs. 4.0% (9/223) (P=0.63), with similar results after adjusting for known DGF predictors. A significantly lower first BPAR rate was observed for longer pump time (as a continuous variable) among more immunologically active recipients (those having more risk factors: DGF, age <50 yr, and non-white) (univariable P=0.005; multivariable P=0.009), with an estimated hazard ratio of 0.43 (P=0.006) favoring pump time more than or equal to 24 hr among those with more than or equal to two risk factors. Conclusions. In this single-center, observational study, MP with prolonged pump times was associated with low DGF/SGF and first BPAR rates, supporting continued use of MP.

Randomized trial of dual antibody induction therapy with steroid avoidance in renal transplantation.

Background. Given our previous experience using dual-induction therapy with antithymocyte globulin (ATG)/daclizumab (Dac) (each with fewer doses than if used alone), we chose to compare two distinct dual-induction strategies. Methods. Single-center, open-label randomized trial of 200 primary kidney transplant recipients was performed: (group I, n=100) ATG/Dac (3 ATG, 2 Dac doses) versus (group II, n=100) ATG/alemtuzumab (1 dose each), with maintenance consisting of reduced tacrolimus dosing (rTd), enteric-coated mycophenolate sodium (EC-MPS), and early corticosteroid withdrawal. One half of standard EC-MPS dosing was targeted in group II to avoid severe leukopenia previously seen with alemtuzumab. The goal in both arms was to achieve rapid and effective lymphocyte depletion while simultaneously allowing reduced maintenance immunosuppression. Primary endpoint was the incidence of biopsy-proven acute rejection (BPAR). Results. With median follow-up of 38 months, there were no differences in BPAR rates: 14 of 100 vs. 13 of 100 (including borderline) and 10 of 100 vs. 9 of 100 (excluding borderline) in groups I and II, respectively (nonsignificant). Actuarial patient/graft survival at 48 months was 96%/91% in group I vs. 92%/83% in group II (N.S.). Mean estimated glomerular filtration rate (±standard error) at 36 months was 72.1±3.3 vs. 67.5±3.3 in groups I and II (N.S.). Greater incidence of leukopenia occurred in group II at month 1 only (P=0.002). Percentages having EC-MPS withheld/discontinued due to leukopenia, gastrointestinal symptoms, and infection were 12 of 100, 7 of 100, and 0 of 100 in group I vs. 19 of 100, 0 of 100, and 2 of 100 in group II, respectively (P=0.01). Rates of new onset diabetes mellitus after transplantation and infections were equally low in both groups (no lymphoproliferative disorders were observed). Conclusions. These two distinct dual-induction therapies with rTd, EC-MPS, and planned early corticosteroid withdrawal resulted in favorable rates of BPAR and all secondary outcomes.

Randomized Trial of Mycophenolate Mofetil Versus Enteric-Coated Mycophenolate Sodium in Primary Renal Transplantation With Tacrolimus and Steroid Avoidance: Four-Year Analysis

Background. Our single-center, open-labeled randomized trial of 150 adult, primary kidney transplant recipients receiving 2 g mycophenolate mofetil (group A, n=75) versus 1.440 g enteric-coated mycophenolate sodium (group B, n=75), with reduced maintenance tacrolimus dosing, steroid elimination at 1 week, and combined rabbit antithymocyte globulin/daclizumab induction, previously showed at 1 year posttransplant low biopsy-proven acute rejection (BPAR), acceptably high renal function, and no differences in incidence of symptomatic gastrointestinal (GI) side effects between the two groups. This report includes 3 additional years of follow-up with similar endpoints as in the original study. Methods. Rates of developing first BPAR, graft failure (death censored and uncensored), death, and adverse events (GI toxicity, infections requiring hospitalization, and new onset diabetes mellitus after transplantation) during the first 48 months posttransplant were compared between the two groups using an intent-to-treat approach. Results. At 48 months posttransplant, patient/graft survival in groups A and B was 97%/90% vs. 96%/86%, respectively (not significant [NS]). Twenty-seven patients experienced BPAR (including borderline), with actuarial 19% (14/75) vs. 18% (13/75) in groups A and B, respectively (NS). Geometric mean*/standard error serum creatinine level and arithmetic mean calculated glomerular filtration rate (±standard error) at 48 months in groups A and B, respectively, were 1.25*/1.06 and 69.2±3.9 vs. 1.20*/1.05 and 71.2±3.2 (NS). Incidence of new onset diabetes mellitus after transplantation (22% vs. 15%), infections requiring hospitalization (31% vs. 39%), and GI side effects (45% vs. 52%) seemed equivalent. Conclusions. This is the first long-term, randomized trial comparing enteric-coated mycophenolate sodium versus mycophenolate mofetil along with reduced maintenance tacrolimus dosing and steroid avoidance, which resulted in similarly low-BPAR rates, acceptably high renal function at 48 months, and an equivalent side effect profile.

Prolonged lymphocyte depletion by single-dose rabbit anti-thymocyte globulin and alemtuzumab in kidney transplantation

Although antibody induction has gained in popularity, two agents are rarely combined. We retrospectively analyzed peripheral lymphocyte phenotypes of renal transplant recipients who received induction therapy with a different antibody/combination: alemtuzumab(C1H), Thymoglobulin(rATG), daclizumab(Dac), rATG+C1H, and rATG+Dac. CD4+ T-cells were suppressed by C1H and rATG+C1H, as well as by rATG and rATG+Dac but to a lesser extent. The effect lasted for 3 years at around 40% of baseline values. CD8+ T-cells showed a similar trend but had a more rapid recovery to baseline. CD19+ B-cells were effectively suppressed for 2 months by C1H and rATG+C1H, and abruptly returned to baseline afterwards; suppression by rATG(7 doses) was modest but lasted longer. A higher proportion of CD56+CD16+ Natural Killer cells in C1H treated patients suggested a relatively spared effect of C1H on this cell type. Low CD25+ T-cells by 5-dose Dac returned to baseline around 6 months, whereas rATG+C1H and rATG+Dac showed persistent effect. CD4+CD25hi T-cells were suppressed by both rATG+C1H and rATG+Dac, but the initial proportion of CD4+CD25hi T-cells among CD4+ T-cells and CD4+CD25hi/CD4+CD25lo ratio were significantly higher in rATG+C1H. Overall, with extensive and persistent lymphocyte suppression by a simple administration of agents, single-dose rATG+C1H induction can be an alternative in renal transplantation.

A randomized pilot study of donor stem cell infusion in living-related kidney transplant recipients receiving alemtuzumab.

Background Transplant tolerance would remove the need for maintenance immunosuppression while improving survival and quality of life. Methods A prospective, randomized pilot study was undertaken to assess the safety and efficacy of donor stem cell infusion (DSCI) in living-related kidney transplant recipients treated with alemtuzumab (C1H) induction and tacrolimus and mycophenolate maintenance with switch to sirolimus and weaning over 2 years. Results Four patients received DSCI; five patients were controls. Graft failure occurred in two patients in the DSCI arm. Recurrence of glomerular disease occurred in two DSCI recipients, leading to graft loss in one. Biopsy-proven acute rejection episodes occurred in three patients (two in the DSCI vs. one in the control). One DSCI patient, with recurrence, subsequently developed antibody-mediated rejection leading to graft failure. In the remaining two DSCI patients, weaning was attempted but was not successful. All (4 of 4) DSCI patients had biopsy-proven chronic allograft injury and/or recurrence. Conclusion DSCI with C1H induction and a steroid-free maintenance regimen in a small group of patients failed to induce tolerance, with suboptimal patient and graft survival. The results do not justify extension of this particular trial and underscore the importance of patient selection, specifically avoidance of patients with glomerulopathies whose recurrence may obscure potential benefit.

Machine perfusion following static cold storage preservation in kidney transplantation: donor‐matched pair analysis of the prognostic impact of longer pump time

The impact of machine perfusion (MP) time on kidney transplant outcome is mixed in previous studies using multivariable analyses. In an analysis of 66 pairs of donor‐matched adult, first transplant recipients (N = 132) with identical donor characteristics except for pump time, tests of association of shorter versus longer pump time (first versus second kidney removed) by delayed graft function(DGF), slow graft function(SGF), and biopsy proven acute rejection(BPAR) were performed using McNemar’s test. Freedom‐from‐BPAR, graft and patient survival, and renal function were also compared. Mean ± SD pump times for paired recipients with first and second kidneys were 22.7 ± 7.3 h and 31.2 ± 7.9 h, respectively (mean difference: 8.5 ± 4.5 h, P < .000001). There was no significant impact of pump time on DGF or SGF, with discordant pairs favoring less SGF with longer pump time (N.S.). The incidence of BPAR during the first 12 months post‐transplant yielded a borderline difference favoring longer pump time (P = .09), and freedom‐from‐BPAR during the first 12 months was significantly more favorable for longer pump times (95% vs. 84%, P = 0.04). No differences were observed in graft and patient survival, and renal function. While offering significantly favorable protection from BPAR, this analysis of donor‐matched recipient pairs corroborates longer MP (pump) times having no unfavorable effect on other clinical outcomes.

PROLONGED COLD ISCHEMIA TIME BEFORE DOUBLE KIDNEY TRANSPLANTATION DOES NOT NEGATIVELY IMPACT ON OUTCOMES WHEN PRESERVED BY PULSATILE MACHINE PERFUSION.: 888

J. Fan1, J. Sageshima2, G. Ciancio3, J.J. Gaynor4, A. Zarak4, L. Chen3, D.A. Grant3, T. Urahashi4, R. Brown4, A. Mattiazzi3, G. Guerra3, W. Kupin3, D. Roth3, S. Ganz3, P. Ruiz3, G.W. Burke, III3 1Kidney/pancreas Transplantation, University of Miami, Miami/ FL/UNITED STATES OF AMERICA, 2Surgery, Kidney/pancreas Transplant, University of Miami Miller School of Medicine, Miami/ Florida/UNITED STATES OF AMERICA, 3Miller School Of Medicine, University of Miami, Miami/UNITED STATES OF AMERICA, 4Surgery, Kidney/pancreas Transplant, University of Miami Miller School of Medicine, Miami/UNITED STATES OF AMERICA