Recurrence of membranous nephropathy after kidney transplantation: A multicenter retrospective cohort study.

Membranous nephropathy (MN) is a leading cause of kidney failure worldwide and frequently recurs after transplant. Available data originated from small retrospective cohort studies or registry analyses; therefore, uncertainties remain on risk factors for MN recurrence and response to therapy. Within the Post-Transplant Glomerular Disease Consortium, we conducted a retrospective multicenter cohort study examining the MN recurrence rate, risk factors, and response to treatment. This study screened 22,921 patients across 3 continents and included 194 patients who underwent a kidney transplant due to biopsy-proven MN. The cumulative incidence of MN recurrence was 31% at 10 years posttransplant. Patients with a faster progression toward end-stage kidney disease were at higher risk of developing recurrent MN (hazard ratio [HR], 0.55 per decade; 95% confidence interval [CI], 0.35-0.88). Moreover, elevated pretransplant levels of anti-phospholipase A2 receptor (PLA2R) antibodies were strongly associated with recurrence (HR, 18.58; 95% CI, 5.37-64.27). Patients receiving rituximab for MN recurrence had a higher likelihood of achieving remission than patients receiving renin-angiotensin-aldosterone system inhibition alone. In sum, MN recurs in one-third of patients posttransplant, and measurement of serum anti-PLA2R antibody levels shortly before transplant could aid in risk-stratifying patients for MN recurrence. Moreover, patients receiving rituximab had a higher rate of treatment response.

Machine learning does not outperform traditional statistical modelling for kidney allograft failure prediction.

Machine learning (ML) models have recently shown potential for predicting kidney allograft outcomes. However, their ability to outperform traditional approaches remains poorly investigated. Therefore, using large cohorts of kidney transplant recipients from 14 centers worldwide, we developed ML-based prediction models for kidney allograft survival and compared their prediction performances to those achieved by a validated Cox-Based Prognostication System (CBPS). In a French derivation cohort of 4000 patients, candidate determinants of allograft failure including donor, recipient and transplant-related parameters were used as predictors to develop tree-based models (RSF, RSF-ERT, CIF), Support Vector Machine models (LK-SVM, AK-SVM) and a gradient boosting model (XGBoost). Models were externally validated with cohorts of 2214 patients from Europe, 1537 from North America, and 671 from South America. Among these 8422 kidney transplant recipients, 1081 (12.84%) lost their grafts after a median post-transplant follow-up time of 6.25 years (Inter Quartile Range 4.33-8.73). At seven years post-risk evaluation, the ML models achieved a C-index of 0.788 (95% bootstrap percentile confidence interval 0.736-0.833), 0.779 (0.724-0.825), 0.786 (0.735-0.832), 0.527 (0.456-0.602), 0.704 (0.648-0.759) and 0.767 (0.711-0.815) for RSF, RSF-ERT, CIF, LK-SVM, AK-SVM and XGBoost respectively, compared with 0.808 (0.792-0.829) for the CBPS. In validation cohorts, ML models' discrimination performances were in a similar range of those of the CBPS. Calibrations of the ML models were similar or less accurate than those of the CBPS. Thus, when using a transparent methodological pipeline in validated international cohorts, ML models, despite overall good performances, do not outperform a traditional CBPS in predicting kidney allograft failure. Hence, our current study supports the continued use of traditional statistical approaches for kidney graft prognostication.

Dynamic prediction of renal survival among deeply phenotyped kidney transplant recipients using artificial intelligence: an observational, international, multicohort study.

BACKGROUND: Kidney allograft failure is a common cause of end-stage renal disease. We aimed to develop a dynamic artificial intelligence approach to enhance risk stratification for kidney transplant recipients by generating continuously refined predictions of survival using updates of clinical data. METHODS: In this observational study, we used data from adult recipients of kidney transplants from 18 academic transplant centres in Europe, the USA, and South America, and a cohort of patients from six randomised controlled trials. The development cohort comprised patients from four centres in France, with all other patients included in external validation cohorts. To build deeply phenotyped cohorts of transplant recipients, the following data were collected in the development cohort: clinical, histological, immunological variables, and repeated measurements of estimated glomerular filtration rate (eGFR) and proteinuria (measured using the proteinuria to creatininuria ratio). To develop a dynamic prediction system based on these clinical assessments and repeated measurements, we used a Bayesian joint models-an artificial intelligence approach. The prediction performances of the model were assessed via discrimination, through calculation of the area under the receiver operator curve (AUC), and calibration. This study is registered with ClinicalTrials.gov, NCT04258891. FINDINGS: 13 608 patients were included (3774 in the development cohort and 9834 in the external validation cohorts) and contributed 89 328 patient-years of data, and 416 510 eGFR and proteinuria measurements. Bayesian joint models showed that recipient immunological profile, allograft interstitial fibrosis and tubular atrophy, allograft inflammation, and repeated measurements of eGFR and proteinuria were independent risk factors for allograft survival. The final model showed accurate calibration and very high discrimination in the development cohort (overall dynamic AUC 0·857 [95% CI 0·847-0·866]) with a persistent improvement in AUCs for each new repeated measurement (from 0·780 [0·768-0·794] to 0·926 [0·917-0·932]; p<0·0001). The predictive performance was confirmed in the external validation cohorts from Europe (overall AUC 0·845 [0·837-0·854]), the USA (overall AUC 0·820 [0·808-0·831]), South America (overall AUC 0·868 [0·856-0·880]), and the cohort of patients from randomised controlled trials (overall AUC 0·857 [0·840-0·875]). INTERPRETATION: Because of its dynamic design, this model can be continuously updated and holds value as a bedside tool that could refine the prognostic judgements of clinicians in everyday practice, hence enhancing precision medicine in the transplant setting. FUNDING: MSD Avenir, French National Institute for Health and Medical Research, and Bettencourt Schueller Foundation.

COVID-19 pandemic and worldwide organ transplantation: a population-based study.

BACKGROUND: Preliminary data suggest that COVID-19 has reduced access to solid organ transplantation. However, the global consequences of the COVID-19 pandemic on transplantation rates and the effect on waitlisted patients have not been reported. We aimed to assess the effect of the COVID-19 pandemic on transplantation and investigate if the pandemic was associated with heterogeneous adaptation in terms of organ transplantation, with ensuing consequences for waitlisted patients. METHODS: In this population-based, observational, before-and-after study, we collected and validated nationwide cohorts of consecutive kidney, liver, lung, and heart transplants from 22 countries. Data were collected from Jan 1 to Dec 31, 2020, along with data from the same period in 2019. The analysis was done from the onset of the 100th cumulative COVID-19 case through to Dec 31, 2020. We assessed the effect of the pandemic on the worldwide organ transplantation rate and the disparity in transplant numbers within each country. We estimated the number of waitlisted patient life-years lost due to the negative effects of the pandemic. The study is registered with ClinicalTrials.gov, NCT04416256. FINDINGS: Transplant activity in all countries studied showed an overall decrease during the pandemic. Kidney transplantation was the most affected, followed by lung, liver, and heart. We identified three organ transplant rate patterns, as follows: countries with a sharp decrease in transplantation rate with a low COVID-19-related death rate; countries with a moderate decrease in transplantation rate with a moderate COVID-19-related death rate; and countries with a slight decrease in transplantation rate despite a high COVID-19-related death rate. Temporal trends revealed a marked worldwide reduction in transplant activity during the first 3 months of the pandemic, with losses stabilising after June, 2020, but decreasing again from October to December, 2020. The overall reduction in transplants during the observation time period translated to 48 239 waitlisted patient life-years lost. INTERPRETATION: We quantified the impact of the COVID-19 pandemic on worldwide organ transplantation activity and revealed heterogeneous adaptation in terms of organ transplantation, both at national levels and within countries, with detrimental consequences for waitlisted patients. Understanding how different countries and health-care systems responded to COVID-19-related challenges could facilitate improved pandemic preparedness, notably, how to safely maintain transplant programmes, both with immediate and non-immediate life-saving potential, to prevent loss of patient life-years. FUNDING: French national research agency (INSERM) ATIP Avenir and Fondation Bettencourt Schueller.

Cholecystectomy-Associated Complications in Kidney Transplant Recipients Compared With the General Population.

Cholelithiasis is one of the most prevalent diseases in the general population. Among kidney transplant (KT) recipients, atypical clinical presentation may delay the diagnosis and proper treatment. This single-center retrospective cohort study compared cholelithiasis clinical presentation and cholecystectomy-associated complications in 230 KT recipients and in 172 members of the general population. KT recipients had a higher proportion of men, comorbidities, biliary pancreatitis, choledocholithiasis, and acute cholecystitis clinical presentations than the general population. KT recipients presented higher American Society of Anesthesiologists scores and higher rates of emergency surgeries (15.7% vs 9.9%, P = .091), conversion (5.7% vs 1.2%, P = .019), drainage (7.8% vs 2.3%, P = .016), postoperative complications (10% vs 4.7%, P = .047), and longer hospital length of stay (1 vs 1 days, interquartile range, 2 vs 0 days; P < .001). There were 5 deaths, all of which occurred in KT recipients. History of diabetes mellitus, renal function, and surgical conversion were independent risk factors associated with postoperative complications. Male sex and level of renal function were independent risk factors associated with postoperative acute cholecystitis. KT was an independent risk factor associated with postoperative choledocholithiasis (adjusted odds ratio, 5.89; 95% confidence interval, 3.03-15.66) and pancreatitis (adjusted odds ratio, 6.89; 95% confidence interval, 2.99-11.61). In conclusion, KT recipients with cholelithiasis have an increased risk for clinical and surgical complications compared with the general population.

Influence of epidemiology, immunosuppressive regimens, clinical presentation, and treatment on kidney transplant outcomes of patients diagnosed with tuberculosis: A retrospective cohort analysis.

Tuberculosis (TB) mortality is high among kidney transplant (KT) recipients. Although local epidemiology is an important factor, diagnostic/therapeutic challenges and immunosuppressive therapy (ISS) may influence outcomes. We analyzed the cumulative incidence (CumI) of TB in KT recipients receiving a variety of ISS with long-term follow-up. Our retrospective single-center cohort study included all KT procedures performed between January 1, 1998, and August 31, 2014, with follow-up until August 31, 2014. Induction therapy was based on perceived immunological risk; maintenance ISS included prednisone and calcineurin inhibitor (CNI) plus azathioprine (AZA), and mycophenolic acid (MPA) or mechanistic target of rapamycin inhibitor (mTORi). Thirty-four patients received belatacept/MPA. KT was performed on 11 453 patients and followed for 1989 (IQR 932 to 3632) days. Among these, 152 patients were diagnosed with TB (CumI 1.32%). Median time from KT to TB was 18.8 (IQR 7.2 to 60) months, with 59% of patients diagnosed after the first year. Unadjusted analysis revealed an increasing confidence interval (CI) of TB (0.94% CNI/AZA vs 1.6% CNI/MPA [HR = 1.62, 95% CI = 1.13 to 2.34, P = .009] vs 2.85% CNI/mTORi [HR = 2.45, 95% CI = 1.49 to 4.32, P < .001] vs 14.7% belatacept/MPA [HR = 13.14, 95% CI = 5.27 to 32.79, P < .001]). Thirty-seven (24%) patients died, and 39 (25.6%) patients experienced graft loss. Cytomegalovirus infection (P = .02) and definitive ISS discontinuation (P < .001) were associated with death. Rejection (P = .018) and ISS discontinuation (P = .005) occurred with graft loss. TB occurred at any time after KT and was influenced by ISS.

Genetic diversity of Pneumocystis jirovecii from a cluster of cases of pneumonia in renal transplant patients: Cross-sectional study.

Pneumocystis jirovecii can cause severe potentially life-threatening pneumonia (PCP) in kidney transplant patients. Prophylaxis of patients against PCP in this setting is usually performed during 6 months after transplantation. The aim of this study is to describe the molecular epidemiology of a cluster of PCP in renal transplant recipients in Brazil. Renal transplant patients who developed PCP between May and December 2011 had their formalin-fixed paraffin-embedded (FFPE) lung biopsy samples analysed. Pneumocystis jirovecii 23S mitochondrial large subunit of ribosomal RNA (23S mtLSU-rRNA), 26S rRNA, and dihydropteroate synthase (DHPS) genes were amplified by polymerase chain reaction (PCR), sequenced, and analysed for genetic variation. During the study period, 17 patients developed PCP (only four infections were documented within the first year after transplantation) and six (35.3%) died. Thirty FFPE samples from 11 patients, including one external control HIV-infected patient, had fungal DNA successfully extracted for further amplification and sequencing for all three genes. A total of five genotypes were identified among the 10 infected patients. Of note, four patients were infected by more than one genotype and seven patients were infected by the same genotype. DNA extracted from FFPE samples can be used for genotyping; this approach allowed us to demonstrate that multiple P. jirovecii strains were responsible for this cluster, and one genotype was found infecting seven patients. The knowledge of the causative agents of PCP may help to develop new initiatives for control and prevention of PCP among patients undergoing renal transplant and improve routine PCP prophylaxis.

Sepsis-like histoplasmosis in a kidney transplant patient.

Histoplasmosis is a fungus infection that mainly affects immunosuppressed patients. The authors present a case of a kidney transplant recipient who developed sepsis-like histoplasmosis, na atypical but severe manifestation of the disease. The fungus was found in blood and in a skin biopsy, and the treatment with liposomal amphotericin resulted in hepatotoxicity.

Sepsis-like histoplasmosis in a kidney transplant patient / Histoplasmose disseminada em uma paciente transplantada renal

Abstract Histoplasmosis is a fungus infection that mainly affects immunosuppressed patients. The authors present a case of a kidney transplant recipient who developed sepsis-like histoplasmosis, na atypical but severe manifestation of the disease. The fungus was found in blood and in a skin biopsy, and the treatment with liposomal amphotericin resulted in hepatotoxicity.

Resumo Histoplasmose é uma infecção fúngica que afeta principalmente pacientes imunossuprimidos. Os autores apresentam um caso de uma receptora de transplante de rim que desenvolveu histoplasmose disseminada, uma manifestação atípica, mas grave da doença. O fungo foi encontrado no sangue e na biópsia cutânea, e o tratamento com anfotericina lipossomal resultou em hepatotoxicidade.

Novel Once-Daily Extended-Release Tacrolimus Versus Twice-Daily Tacrolimus in De Novo Kidney Transplant Recipients: Two-Year Results of Phase 3, Double-Blind, Randomized Trial.

BACKGROUND: 1-year data from this trial showed the noninferiority of a novel once-daily extended-release tacrolimus (LCPT; Envarsus XR) to immediate-release tacrolimus (IR-Tac) twice daily after kidney transplantation. STUDY DESIGN: Final 24-month analysis of a 2-armed, parallel-group, randomized, double-blind, double-dummy, multicenter, phase 3 trial. SETTING & PARTICIPANTS: 543 de novo kidney recipients randomly assigned to LCPT (n=268) or IR-Tac (n=275); 507 (93.4%) completed the 24-month study. INTERVENTION: LCPT tablets once daily at 0.17 mg/kg/d or IR-Tac twice daily at 0.1 mg/kg/d; subsequent doses were adjusted to maintain target trough ranges (first 30 days, 6-11 ng/mL; thereafter, 4-11 ng/mL). The intervention was 24 months; the study was double blinded for the entirety. OUTCOMES & MEASUREMENTS: Treatment failure (death, transplant failure, biopsy-proven acute rejection, or loss to follow up) within 24 months. Safety end points included adverse events, serious adverse events, new-onset diabetes, kidney function, opportunistic infections, and malignancies. Pharmacokinetic measures included total daily dose (TDD) of study drugs and tacrolimus trough levels. RESULTS: 24-month treatment failure was LCPT, 23.1%; IR-Tac, 27.3% (treatment difference, -4.14% [95% CI, -11.38% to +3.17%], well below the +10% noninferiority criterion defined for the primary 12-month end point). Subgroup analyses showed fewer treatment failures for LCPT versus IR-Tac among black, older, and female recipients. Safety was similar between groups. From month 1, TDD was lower for LCPT; the difference increased over time. At month 24, mean TDD for LCPT was 24% lower than for the IR-Tac group (P<0.001), but troughs were similar (means at 24 months: LCPT, 5.47 ± 0.17 ng/mL; IR-Tac, 5.8 ± 0.30 ng/mL; P=0.4). LIMITATIONS: Trial participant eligibility criteria may limit the generalizability of results to the global population of de novo kidney transplant recipients. CONCLUSIONS: Results suggest that once-daily LCPT in de novo kidney transplantation has comparable efficacy and safety profile to that of IR-Tac. Lower TDD reflects LCPT's improved bioavailability and absorption.

Risk assessment score in pre-kidney transplantation: methodology and the socioeconomic characteristics importance.

INTRODUCTION: Kidney transplantation is performed in emergency conditions in a population with high perioperative risk. Instruments for risk assessment before transplantation in this population are scarce. OBJECTIVE: To develop a score with pretransplant variables to estimate the probability of success of kidney transplantation, defined as survival of the recipient and the graft with creatinine < 1.5 mg/dl at 6 months. METHODS: Analysis of variables of patients from a unique kidney transplantation center in São Paulo. Logistic regression was used to construct an equation with variables able to estimate the probability of success. Integer points were assigned to variables for score construction. RESULTS: Of the 305 patients analyzed, 176 (57.7%) achieved success. Of the 23 variables identified by univariate analysis, 21 were included in the logistic regression model and 10 that remained independently associated with success, were used in the score. Four of these 10 variables were socioeconomic. It was great (area under the ROC curve 0.817) the power of discrimination between groups success and not success and adequate (Hosmer and Lemeshow = 0.672) the agreement between frequencies of the probabilities estimated by equation and frequencies of probabilities actual observed. There were correlation (0.982) between the estimated probability via the scoring system and the estimated probabilities via logistic regression. CONCLUSION: Point score simplified risk stratification of transplant candidate according to their probability of success. Socioeconomic variables influence the success, demonstrating the need for creation of prognostic tools utilizing clinical and demographic variables of our population.

Long-term follow-up of a phase III clinical trial comparing tacrolimus extended-release/MMF, tacrolimus/MMF, and cyclosporine/MMF in de novo kidney transplant recipients.

BACKGROUND: In a phase III, open-label, comparative, noninferiority study, 638 subjects receiving de novo kidney transplants were randomized to one of three treatment arms: tacrolimus extended-release (Astagraf XL) qd, tacrolimus (Prograf) bid, or cyclosporine (CsA) bid. All subjects received basiliximab induction, mycophenolate mofetil, and corticosteroids. Safety and efficacy follow-up data through 4 years are reported. METHODS: Evaluations included patient and graft survival, study drug discontinuations, laboratory values including renal function and development of new-onset diabetes after transplantation, concomitant medications, and adverse events. RESULTS: At study termination, 129 Astagraf XL, 113 Prograf, and 79 CsA patients had continued follow-up. Demographic and baseline characteristics were similar in all arms. Four-year Kaplan-Meier estimates of patient survival in the Astagraf XL, Prograf, and CsA groups were 93.2, 91.2, and 91.7%, respectively, while graft survival was 84.7, 82.7, and 83.9%, respectively. At least one serious adverse event was reported in the majority of patients in each group during the study (65.9% Astagraf XL, 69.8% Prograf, and 65.6% CsA). Renal function was not significantly different between Astagraf XL and Prograf. HgbA1c levels were collected every 6 months; the 4-year Kaplan-Meier estimate for incidence of HgbA1c levels ≥ 6.5% was significantly higher for both tacrolimus formulations compared to CsA; 41.1% (Astagraf XL), 33.6% (Prograf), and 21.3% (CsA). CONCLUSIONS: In this 4-year follow-up report, patients receiving Astagraf XL and Prograf showed comparable efficacy and safety profiles, with a higher incidence of new-onset diabetes after transplantation but superior renal function compared to patients receiving CsA.

Randomized trial of everolimus-facilitated calcineurin inhibitor minimization over 24 months in renal transplantation.

BACKGROUND: Strategies allowing calcineurin inhibitor minimization while maintaining efficacy may improve renal transplant outcomes. METHODS: A2309 was a 24-month, phase IIIb, open-label trial of 833 de novo renal transplant recipients randomized to everolimus, targeting trough concentrations of 3-8 or 6-12 ng/mL plus reduced-exposure cyclosporine A (CsA) or to mycophenolic acid (MPA) 1.44 g per day plus standard-exposure CsA. All patients received basiliximab ± corticosteroids. The incidence of the primary composite efficacy endpoint and its components (treated biopsy-proven acute rejection, graft loss, death, or loss to follow-up), renal function (serum creatinine and estimated glomerular filtration rate), and adverse events (AEs) were compared at 24 months; as per the protocol, these analyses were not noninferiority. RESULTS: Composite efficacy failure rates (95% confidence interval for difference vs. MPA) were 32.9% (-2.2%, 13.0%), 26.9% (-7.9%, 6.8%), and 27.4% at month 24 in the everolimus 3-8 and 6-12 ng/mL and MPA groups, respectively. Mean estimated glomerular filtration rate (Modification of Diet in Renal Disease) at month 24 was 52.2 (-2.1, 5.5 mL/min/1.73 m(2)), 49.4 (-4.8, 2.7 mL/min/1.73 m(2)), and 50.5 mL/min/1.73 m(2), respectively. AEs were generally mild to moderate in severity and comparable between the groups. AEs leading to discontinuation were reported in 28.5% (P = 0.03 vs. MPA), 30.6% (P = 0.007 vs. MPA), and 20.5% of patients receiving everolimus 3-8 and 6-12 ng/mL and MPA, respectively. CONCLUSIONS: Everolimus trough concentrations targeted to 3-8 ng/mL, along with a greater than 60% reduction in CsA exposure, was associated with comparable efficacy and renal function versus MPA plus standard-exposure CsA over the 2-year period. A significantly higher incidence of AEs led to discontinuation in the everolimus groups compared with the MPA group.

Influence of deceased donor hemodynamic factors in transplant recipients renal function.

INTRODUCTION: The incidence of delayed graft function (DGF) and unsatisfactory creatinine clearance (UCC) after renal transplantation is significantly higher in Brazil, when compared with that observed in United States or Europe. Deceased donor (DD) characteristics should directly influence the occurrence of these two outcomes. OBJECTIVE: This study aim to evaluate the influence of DD characteristics on DGF and UCC incidence in Brazil. METHODS: DD clinical and laboratory variables were correlated with outcome's incidence. RESULTS: We evaluated 787 DD whose organs were transplanted in 1298 patients. We noted a high prevalence of vasoactive drugs use (90.2%), hypernatremia (66.6%) and renal dysfunction (34.8%). The incidence of DGF and UCC was 60.6% and 55.2%, respectively. We observed a progressive increase in DGF risk for age groups over 30 years and for cold ischemia time (CIT) greater than 24 hours. DGF risk was two times higher in recipients of donor kidney final serum creatinine (Cr) over than 1.5 mg/dl. Hypertension and CIT over 36 hours was associated with an increasing of 82% and 99% in UCC risk, respectively. Donor age above 40 years was associated with a progressive increase in UCC risk. CONCLUSION: DD age, renal function, hypertension and prolonged CIT were associated with increased risk DGF and UCC.

Decrease in oral health may be associated with length of time since beginning dialysis.

The aim of this study was to evaluate how oral health is affected by the length of time a patient has been receiving hemodialysis (HD) treatment. Ninety-four subjects participated in this study. Demographic, periodontal parameters, and decayed missing and filled teeth (DMFT) index were recorded by a trained and calibrated examiner. The subjects were divided into two groups: Group L (subjects who had been on HD for less than 36 months), and Group M (those who had been on HD for more than 37 months). In Group M, the mean probing depth was deeper (p= 0.01) and clinical attachment loss was significantly higher (p= 0.02) than subjects in Group L. The DMFT index score was also significantly higher in Group M (p= 0.03). A moderate correlation between length of time on HD and DMFT index, probing depth, and clinical attachment loss was observed. The group of subjects who had been on HD for more than 37 months had more periodontal disease and higher DMFT index scores, suggesting that the length of time on HD could negatively impact oral health.

How delayed graft function impacts exposure to mycophenolic acid in patients after renal transplantation.

INTRODUCTION: Mycophenolic acid (MPA) plasma concentrations are highly variable on standard-dose mycophenolate mofetil therapy. At creatinine clearances below 25 mL/min, MPA clearance increases as a result of a higher nonprotein-bound fraction. Patients with delayed graft function (DGF) after renal transplantation are exposed to low total MPA concentrations, when risk of rejection is highest. This study investigated the influence of DGF on MPA exposure and on clinical outcome. METHODS: Adult renal transplantation patients treated with mycophenolate mofetil, corticosteroids, and either microemulsified cyclosporine (n = 459) or tacrolimus (n = 371) participated in a randomized controlled trial (the Fixed-Dose Concentration-Controlled [FDCC] Study). Abbreviated MPA areas under the curve (AUCs) were obtained on Day 3, Day 10, Week 4, and Month 3, to calculate MPA AUC0₋12. Free MPA AUC values were available for a subgroup of patients (n = 269). RESULTS: The overall incidence of DGF was 187 of 830 (23%) and did not differ between cyclosporine-treated (24%) and tacrolimus- (21%) treated patients. The incidence of biopsy-proven acute rejection at 12 months was significantly higher in patients with DGF (13.8% versus 21.4%). Patients with DGF had significantly lower dose-corrected MPA AUC on Day 3 and Day 10. Free MPA fraction and dose-corrected free MPA AUC were significantly higher in patients with DGF, from Day 3 until Month 3. The total number of patients with at least one opportunistic infection was significantly higher in patients with DGF (33.2%) compared with patients without DGF (25.8%) (P = 0.048). Patients with DGF developing opportunistic infections did not have higher total MPA AUC nor higher free MPA AUC compared with those without opportunistic infections. CONCLUSION: Patients with DGF have significantly lower dose-corrected MPA AUC in the first month after renal transplantation, presumably as a result of enhanced MPA clearance on account of the elevated MPA free fraction. Because patients with DGF have a higher rate of acute rejection and lower MPA exposure, higher dosing of mycophenolate mofetil in such patients may improve outcome. However, the already increased incidence of opportunistic infections in patients with DGF is a concern.

Comparing mycophenolate mofetil regimens for de novo renal transplant recipients: the fixed-dose concentration-controlled trial.

BACKGROUND: Fixed-dose mycophenolate mofetil (MMF) reduces the incidence of acute rejection after solid organ transplantation. The Fixed-Dose Concentration Controlled trial assessed the feasibility and potential benefit of therapeutic drug monitoring in patients receiving MMF after de novo renal transplant. METHODS: Patients were randomized to a concentration-controlled (n=452; target exposure 45 mg hr/L) or a fixed-dose (n=449) MMF-containing regimen. The primary endpoint was treatment failure (a composite of biopsy-proven acute rejection [BPAR], graft loss, death, or MMF discontinuation) by 12 months posttransplantation. RESULTS: Mycophenolic acid (MPA) exposures for both groups were similar at most time points and were below 30 mg hr/L in 37.3% of patients at day 3. There was no difference in the incidence of treatment failure (25.6% vs. 25.7%, P=0.81) or BPAR (14.9% vs. 15.5%, P>0.05) between the concentration-controlled and the fixed-dose groups, respectively. We did find a significant relationship between MPA-area under the concentration-time curve on day 3 and the incidence of BPAR in the first month (P=0.009) or in the first year posttransplantation (P=0.006). For later time points (day 10, month 1) there was no significant relationship between area under the concentration-time curve and BPAR (0.2572 and 0.5588, respectively). CONCLUSIONS: There was no difference in the incidence of treatment failure between the concentration-controlled and the fixed-dose groups. The applied protocol of MMF dose adjustments based on target MPA exposure was not successful, partly because physicians seemed reluctant to implement substantial dose changes. Current initial MMF doses underexpose more than 35% of patients early after transplantation, increasing the risk for BPAR.