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Dive into the research topics where Karl Martin Wissing is active.

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Featured researches published by Karl Martin Wissing.


JAMA | 2010

Mycophenolate Mofetil vs Azathioprine for Remission Maintenance in Antineutrophil Cytoplasmic Antibody–Associated Vasculitis: A Randomized Controlled Trial

Thomas F. Hiemstra; Michael P. Walsh; Alfred Mahr; Caroline O. S. Savage; Kirsten de Groot; Lorraine Harper; Thomas H. Hauser; Irmgard Neumann; Vladimir Tesar; Karl Martin Wissing; Christian Pagnoux; Wilhelm H. Schmitt; David Jayne

CONTEXT Current remission maintenance therapies for antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) are limited by partial efficacy and toxicity. OBJECTIVE To compare the effects of mycophenolate mofetil with azathioprine on the prevention of relapses in patients with AAV. DESIGN, SETTING, AND PARTICIPANTS Open-label randomized controlled trial, International Mycophenolate Mofetil Protocol to Reduce Outbreaks of Vasculitides (IMPROVE), to test the hypothesis that mycophenolate mofetil is more effective than azathioprine for preventing relapses in AAV. The trial was conducted at 42 centers in 11 European countries between April 2002 and January 2009 (42-month study). Eligible patients had newly diagnosed AAV (Wegener granulomatosis or microscopic polyangiitis) and were aged 18 to 75 years at diagnosis. INTERVENTIONS Patients were randomly assigned to azathioprine (starting at 2 mg/kg/d) or mycophenolate mofetil (starting at 2000 mg/d) after induction of remission with cyclophosphamide and prednisolone. MAIN OUTCOME MEASURES The primary end point was relapse-free survival, which was assessed using a Cox proportional hazards model. The secondary end points were Vasculitis Damage Index, estimated glomerular filtration rate, and proteinuria. RESULTS A total of 156 patients were assigned to azathioprine (n = 80) or mycophenolate mofetil (n = 76) and were followed up for a median of 39 months (interquartile range, 0.66-53.6 months). All patients were retained in the analysis by intention to treat. Relapses were more common in the mycophenolate mofetil group (42/76 patients) compared with the azathioprine group (30/80 patients), with an unadjusted hazard ratio (HR) for mycophenolate mofetil of 1.69 (95% confidence interval [CI], 1.06-2.70; P = .03). Severe adverse events did not differ significantly between groups. There were 22 severe adverse events in 13 patients (16%) in the azathioprine group and there were 8 severe adverse events in 8 patients (7.5%) in the mycophenolate mofetil group (HR, 0.53 [95% CI, 0.23-1.18]; P = .12). The secondary outcomes of Vasculitis Damage Index, estimated glomerular filtration rate, and proteinuria did not differ significantly between groups. CONCLUSIONS Among patients with AAV, mycophenolate mofetil was less effective than azathioprine for maintaining disease remission. Both treatments had similar adverse event rates. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00307645.


American Journal of Transplantation | 2011

The ORION study: comparison of two sirolimus-based regimens versus tacrolimus and mycophenolate mofetil in renal allograft recipients.

Stuart M. Flechner; Maciej Glyda; Sandra M. Cockfield; Josep M. Grinyó; Christophe Legendre; Graeme R. Russ; Steven Steinberg; Karl Martin Wissing; SandiSee Tai

Safety and efficacy of two sirolimus (SRL)‐based regimens were compared with tacrolimus (TAC) and mycophenolate mofetil (MMF). Renal transplantation recipients were randomized to Group 1 (SRL+TAC; week 13 TAC elimination [n = 152]), Group 2 (SRL + MMF [n = 152]) or Group 3 (TAC + MMF [n = 139]). Group 2, with higher‐than‐expected biopsy‐confirmed acute rejections (BCARs), was sponsor‐terminated; therefore, Group 2 two‐year data were limited. At 1 and 2 years, respectively, graft (Group 1: 92.8%, 88.5%; Group 2: 90.6%, 89.9%; Group 3: 96.2%, 95.4%) and patient (Group 1: 97.3%, 94.4%; Group 2: 95.2%, 94.5%; Group 3: 97.0%, 97.0%) survival rates were similar. One‐ and 2‐year BCAR incidence was: Group 1, 15.2%, 17.4%; Group 2, 31.3%, 32.8%; Group 3, 8.2%, 12.3% (Group 2 vs. 3, p < 0.001). Mean 1‐ and 2‐year modified intent‐to‐treat glomerular filtration rates (mL/min) were similar. Primary reason for discontinuation was adverse events (Group 1, 34.2%; Group 2, 33.6%; Group 3, 22.3%; p < 0.05). In Groups 1 and 2, delayed wound healing and hyperlipidemia were more frequent. One‐year post hoc analysis of new‐onset diabetes posttransplantation was greater in TAC recipients (Groups 1 and 3 vs. 2, 17% vs. 6%; p = 0.004). Between‐group malignancy rates were similar. The SRL‐based regimens were not associated with improved outcomes for kidney transplantation patients.


Journal of The American Society of Nephrology | 2009

Daclizumab versus Antithymocyte Globulin in High-Immunological-Risk Renal Transplant Recipients

Christian Noel; Daniel Abramowicz; Dominique Durand; Georges Mourad; Philippe Lang; Michèle Kessler; Bernard Charpentier; Guy Touchard; François Berthoux; Pierre Merville; Nacera Ouali; Jean-Paul Squifflet; François Bayle; Karl Martin Wissing; Marc Hazzan

Nondepleting anti-CD25 monoclonal antibodies (daclizumab) and depleting polyclonal antithymocyte globulin (Thymoglobulin) both prevent acute rejection, but these therapies have not been directly compared in a high-risk, HLA-sensitized renal transplant population. We randomly assigned 227 patients, who were about to receive a kidney graft from a deceased donor, to either Thymoglobulin or daclizumab if they met one of the following risk factors: current panel reactive antibodies (PRA) >30%; peak PRA >50%; loss of a first kidney graft from rejection within 2 yr of transplantation; or two or three previous grafts. Maintenance immunosuppression comprised tacrolimus, mycophenolate mofetil, and steroids. Compared with the daclizumab group, patients treated with Thymoglobulin had a lower incidence of both biopsy-proven acute rejection (15.0% versus 27.2%; P = 0.016) and steroid-resistant rejection (2.7% versus 14.9%; P = 0.002) at one year. One-year graft and patient survival rates were similar between the two groups. In a comparison of rejectors and nonrejectors, overall graft survival was significantly higher in the rejection-free group (87.2% versus 75.0%; P = 0.037). In conclusion, among high-immunological-risk renal transplant recipients, Thymoglobulin is superior to daclizumab for the prevention of biopsy-proven acute rejection, but there is no significant benefit to one-year graft or patient survival.


Transplantation | 2000

Hypercholesterolemia is associated with increased kidney graft loss caused by chronic rejection in male patients with previous acute rejection

Karl Martin Wissing; Daniel Abramowicz; Nilufer Broeders; Pierre Vereerstraeten

BACKGROUND Whereas acute rejection is the main risk factor for the occurrence of chronic rejection, mechanisms in addition to the donor-specific immune response probably contribute to late allograft failure. In this study, we investigated the possible role of hypercholesterolemia in the incidence of chronic kidney graft loss. METHODS By using the actuarial method, we retrospectively analyzed the long-term loss of cadaveric kidney grafts in patients who had a functioning graft at 1 year and had received a transplant and undergone cyclosporin A therapy in our center between 1983 and 1997. RESULTS As observed previously, patients with acute rejection during the 1st posttransplant year (n=198) had significantly higher actuarial graft loss at 10 years compared with those free of acute rejection (n=244). In patients free of acute rejection at 1 year, hypercholesterolemia (> or =250 mg/dl) had no impact on graft loss at 10 years. On the contrary, in patients with previous acute rejection, those with hypercholesterolemia (n=59) had a higher immunological (36.0% vs. 19.2%; P<0.01) and overall (50.0% vs. 25.3%; P<0.01) graft loss at 10 years compared with patients with serum cholesterol <250 mg/dl (n=139). Among patients with 1st year acute rejection, hypercholesterolemia was associated with a significant increase in graft loss in male but not in female recipients. Multivariate analysis confirmed that hypercholesterolemia was an independent risk factor for chronic graft loss in male patients (P<0.05). CONCLUSION Hypercholesterolemia is an independent risk factor for kidney graft loss from chronic rejection in male patients with previous acute rejection. Correction of hypercholesterolemia could help to reduce kidney graft loss caused by chronic rejection in this category of patients.


Transplantation | 2008

Cold ischemia is a major determinant of acute rejection and renal graft survival in the modern era of immunosuppression.

Dimitri Mikhalski; Karl Martin Wissing; Lidia Ghisdal; Nilufer Broeders; Marie Touly; Anh Dung Hoang; Patricia Loi; Freddy Mboti; Vincent Donckier; Pierre Vereerstraeten; Daniel Abramowicz

Background. The aim of our study was to examine, in a recent cohort of kidney transplant recipients who have received modern immunosuppressive therapy, the respective role of cold ischemia time (CIT) and delayed graft function (DGF) on acute rejection (AR) rates and long-term graft survival. Methods. We retrospectively reviewed the charts of 611 renal transplantations between 1996 and 2005. Most patients received a calcineurin inhibitor as maintenance therapy, either cyclosporine (43%) or tacrolimus (52%) and 76% of the patients received an antilymphocyte induction therapy. Study endpoints were DGF, first-year AR, and long-term graft survival. Uni- and multivariate analyses were performed to determine factors that may have influenced the study outcomes. Results. DGF was observed in 16.2% of patients. Both older donor age and longer CIT were significant risk factors for DGF. DGF rates were similar whether patients received a calcineurin inhibitor before transplantation or not. AR occurred in 16.5% of grafts during the first year. Independent predictors of AR by multivariate analysis were duration of dialysis, CIT, current panel-reactive lymphocytotoxic antibody more than 5%, and the number of human leukocyte antigen-A, B, and DR mismatches. Each hour of cold ischemia increases the risk of rejection by 4%. With respect to death-censored graft survival, three pretransplant parameters emerged as independent predictors of graft loss: younger recipient age, peak panel-reactive lymphocytotoxic antibody more than 5% and longer CIT. The detrimental effect of CIT on graft survival was entirely because of its propensity to trigger AR. When AR was added to the multivariate Cox model, CIT was no longer significant whereas first-year AR became the most important predictor of graft loss (Hazards ratio, 4.6). Conclusion. Shortening CIT will help to decrease not only DGF rates but also AR incidence and hence graft loss. Patients with prolonged CIT should receive adequate immunosuppression, possibly with antilymphocyte preparations, to prevent AR occurrence.


American Journal of Transplantation | 2011

Sotrastaurin, a novel small molecule inhibiting protein-kinase C: Randomized phase II study in renal transplant recipients

Styrbjörn Friman; Wolfgang Arns; Björn Nashan; Flavio Vincenti; Bernhard Banas; Klemens Budde; Diane M. Cibrik; Lingtakneander Chan; Jürgen Klempnauer; Shamkant Mulgaonkar; Michael L. Nicholson; Jan Wahlberg; Karl Martin Wissing; Ken Abrams; Steffen Witte; E S. Woodle

Sotrastaurin, a selective protein‐kinase‐C inhibitor, blocks early T‐cell activation through a calcineurin‐independent mechanism. In this study, de novo renal transplant recipients with immediate graft function were randomized 1:2 to tacrolimus (control, n = 44) or sotrastaurin (300 mg b.i.d.; n = 81). All patients received basiliximab, mycophenolic acid (MPA) and steroids. The primary endpoint was the composite of treated biopsy‐proven acute rejection (BPAR), graft loss, death or lost to follow‐up at month 3. The main safety assessment was estimated glomerular filtration rate (eGFR); modification of diet in renal disease (MDRD) at month 3. Composite efficacy failure at month 3 was higher for the sotrastaurin versus control regimen (25.7% vs. 4.5%, p = 0.001), driven by higher BPAR rates (23.6% vs. 4.5%, p = 0.003), which led to early study termination. Median (± standard deviation [SD]) eGFR was higher for sotrastaurin versus control at all timepoints from day 7 (month 3: 59.0 ± 22.3 vs. 49.5 ± 17.7 mL/min/1.73 m2, p = 0.006). The most common adverse events were gastrointestinal disorders (control: 63.6%; sotrastaurin: 88.9%) which led to study‐medication discontinuation in two sotrastaurin patients. This study demonstrated a lower degree of efficacy but better renal function with the calcineurin‐inhibitor‐free regimen of sotrastaurin+MPA versus the tacrolimus‐based control. Ongoing studies are evaluating alternative sotrastaurin regimens.


American Journal of Kidney Diseases | 2008

Late Onset of Bladder Urothelial Carcinoma After Kidney Transplantation for End-Stage Aristolochic Acid Nephropathy: A Case Series With 15-Year Follow-up

Anne Lemy; Karl Martin Wissing; Sandrine Rorive; Alexandre R. Zlotta; Thierry Roumeguere; Marie Carmen Muniz Martinez; Christine Decaestecker; Isabelle Salmon; Daniel Abramowicz; Jean-Louis Vanherweghem; Joëlle Nortier

BACKGROUND Aristolochic acids are nephrotoxins and predispose to upper-tract urothelial carcinoma. The risk of bladder urothelial carcinoma after kidney transplantation and its relationship to upper-tract urothelial carcinoma is not well defined. STUDY DESIGN Case series. SETTING & PARTICIPANTS Single-center cohort of 38 women given kidney transplants for end-stage aristolochic acid nephropathy. OUTCOMES & MEASUREMENTS The prevalence of upper urinary tract urothelial carcinoma was determined by collecting pathological results of specimens obtained by means of bilateral ureteronephrectomy. We also established the cumulative incidence of bladder urothelial carcinoma in biopsies performed during prospective screening cystoscopies during a 15-year follow-up. RESULTS Upper-tract urothelial carcinoma was found in 17 patients with aristolochic acid nephropathy (44.7%). During follow-up, bladder urothelial carcinoma was diagnosed in 15 patients 68 to 169 months after cessation of aristolochic acid exposure (39.5%): 8 urothelial carcinoma in situ, 4 noninvasive low-grade papillary urothelial carcinoma, and 3 infiltrating urothelial carcinoma. 12 of 17 patients (71%) with a history of upper-tract urothelial carcinoma developed bladder urothelial carcinoma during follow-up, whereas this occurred in only 3 of 21 patients (14%) without upper-tract urothelial carcinoma (P < 0.01). Despite local and/or systemic chemotherapy, 3 patients died and 2 radical cystectomies were performed. LIMITATIONS Small sample size of this case series. CONCLUSIONS Upper-tract and bladder urothelial carcinoma are dramatic complications in kidney transplant recipients with aristolochic acid nephropathy, confirming the carcinogenic properties of aristolochic acids. We identified upper-tract urothelial carcinoma as a potent risk factor for the subsequent development of bladder urothelial carcinoma after kidney transplantation for aristolochic acid nephropathy. Because this complication may occur years after aristolochic acid discontinuation, we suggest regular cystoscopies in addition to the bilateral ureteronephrectomy in kidney transplant recipients with aristolochic acid nephropathy.


Transplant International | 2007

Conversion from tacrolimus to cyclosporine A for new-onset diabetes after transplantation: a single-centre experience in renal transplanted patients and review of the literature

Lidia Ghisdal; Nora Ben Bouchta; Nilufer Broeders; Laurent Crenier; Anh Dung Hoang; Daniel Abramowicz; Karl Martin Wissing

Tacrolimus (TRL) increases the incidence of new‐onset diabetes mellitus after transplantation (NODAT). Little is known about whether conversion from TRL to cyclosporine A (CsA) improves glucose metabolism in patients with NODAT. We retrospectively analysed glucose metabolism parameters in 54 TRL‐treated renal transplant patients who developed NODAT. Thirty‐four were converted to CsA whereas 20 patients continued TRL. After conversion, fasting plasma glucose decreased from 146 ± 64 to 104 ± 20 mg/dl (P < 0.0001) and HbA1c levels decreased from 6.8 ± 0.8% to 6.0 ± 0.6% (P < 0.0001) after 1 year of follow‐up. The remission rate of NODAT reached 42% (95% confidence interval 24–59%) 1 year after conversion versus 0% in the control group (P = 0.001). Blood pressure and lipid levels were stable after conversion although the use of statins significantly increased (P < 0.01). The conversion was safe in terms of graft function and acute rejection episodes. The 1‐year patient survival and graft survival rate were 100%. In conclusion, our results suggest a significant improvement of glucose metabolism after conversion to CsA in renal transplant patients with NODAT.


Transplantation | 2011

Conversion From Prograf to Advagraf Among Kidney Transplant Recipients Results in Sustained Decrease in Tacrolimus Exposure

Jean-Michel Hougardy; Nilufer Broeders; Mireille Kianda; Annick Massart; Phillippe Madhoun; Alain Le Moine; Anh Dung Hoang; Dimitri Mikhalski; Karl Martin Wissing; Daniel Abramowicz

Background. Advagraf is a slow release form of tacrolimus with once-daily formulation. The potential advantages of Advagraf are better adherence and a safer profile by avoiding toxic peak concentrations. In this study, we evaluated the required daily doses of tacrolimus and subsequent blood levels on conversion from Prograf to Advagraf among kidney transplant recipients. Methods. We retrospectively reviewed data from 55 patients for whom a switch from Prograf to Advagraf was identified. Tacrolimus daily doses and concomitant blood levels were analyzed at several time points ranging from 3 months before to 6 months after conversion. Results. We observed a significant increase in tacrolimus daily doses, starting with a dose of 0.063 mg/kg of Prograf, increasing up to 0.081 mg/kg of Advagraf at 6 months (P<0.0001). After conversion, we observed a quick and sustained decrease in trough tacrolimus levels, decreasing from 8.05 ng/mL at day 0 to 6.30 ng/mL at day 180 (P=0.0009). At 6 months, 35% of patients experienced a decrease in trough levels of more than 30%. Creatinine values remained stable over time, and no patient experienced an acute rejection episode. Conclusions. Contrary to the manufacturer instructions, we found a significant decrease in tacrolimus exposure after switching to Advagraf. Therefore, the switch from Prograf to Advagraf should be performed under close medical supervision.


Transplantation | 1997

A pilot trial of recombinant human interleukin-10 in kidney transplant recipients receiving OKT3 induction therapy.

Karl Martin Wissing; Emmanuel Morelon; Christophe Legendre; Luc De Pauw; A LeBeaut; P Grint; M Maniscalki; Brigitte Ickx; Pierre Vereerstraeten; Lucienne Chatenoud; Henri Kreis; Michel Goldman; Daniel Abramowicz

BACKGROUND We conducted a randomized, double-blind, placebo-controlled, rising single-dose study to investigate the effects of recombinant human (rh) interleukin (IL) 10 in renal transplant patients who received OKT3 as induction therapy. METHODS Patients received 0.1 (n=6), 1 (n=6), or 10 microg/kg (n=3) rhIL-10 or placebo (n=6) intravenously 30 min before the first injection of 5 mg of OKT3. We monitored IL-10 serum levels, the effect of rhIL-10 on OKT3-induced cytokine production, clinical toxicity, and the incidence of immunization against OKT3. RESULTS Serum IL-10 levels in the three experimental groups reached 0.8+/-0.2, 7.9+/-1.3, and 118.6+/-7.3 ng/ml (mean+/-SEM), respectively, 30 min after rhIL-10 injection. Peak plasma levels of tumor necrosis factor-alpha (TNF-alpha) were reduced from 2953+/-1599 pg/ml in patients injected with OKT3 and placebo to 447+/-155, 703+/-246, and 459+/-246 pg/ml in patients injected with 0.1, 1, and 10 microg/kg rhIL-10, respectively. Values for 24-hr TNF-alpha area under the curve decreased from 8988+/-3551 pg x hr/ml in control patients to 2284+/-494, 3950+/-955, and 2420+/-931 pg x hr/ml for the 0.1, 1, and 10 microg/kg rhIL-10 dose groups, respectively (P=0.045). There was also a trend toward reduced plasma levels of IL-2, IL-8, and interferon-gamma in rhIL-10-pretreated patients. Although none of the patients who received placebo or 0.1 or 1 microg/kg rhIL-10 developed an IgM antibody response directed against OKT3 during the first 10 days, this occurred in all three patients who received the highest rhIL-10 dose. In two of these patients, neutralization of OKT3 was associated with a reversible acute rejection episode. CONCLUSIONS Pretreatment with doses of up to 1 microg/kg rhIL-10 is safe and reduces the release of TNF-alpha induced by OKT3. However, higher doses might promote early sensitization to OKT3.

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Daniel Abramowicz

Université libre de Bruxelles

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Anne Lemy

Université libre de Bruxelles

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Lidia Ghisdal

Université libre de Bruxelles

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Nilufer Broeders

Université libre de Bruxelles

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Anh Dung Hoang

Université libre de Bruxelles

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Pierre Vereerstraeten

Université libre de Bruxelles

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Annick Massart

Université libre de Bruxelles

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Dimitri Mikhalski

Université libre de Bruxelles

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Judith Racapé

Université libre de Bruxelles

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Mireille Kianda

Université libre de Bruxelles

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