Tacrolimus-related adverse effects in liver transplant recipients: its association with trough concentrations

Anti-intercellular adhesion molecule 1 monomaintenance therapy induced long-term liver allograft survival without chronic rejection

Calcineurin inhibitors (CNIs) are essential in liver transplantation (LT); however, their long-term use leads to various adverse effects. The anti-intercellular adhesion molecule (ICAM)-1 monoclonal antibody MD3 is a potential alternative to CNI. Despite its promising results with short-term therapy, overcoming the challenge of chronic rejection remains important. Thus, we aimed to investigate the outcomes of long-term MD3 therapy with monthly MD3 monomaintenance in nonhuman primate LT models. Rhesus macaques underwent major histocompatibility complex-mismatched allogeneic LT. The conventional immunosuppression group (Con-IS, n = 4) received steroid, tacrolimus, and sirolimus by 4 months posttransplantation. The induction MD3 group (IN-MD3, n = 5) received short-term MD3 therapy for 3 months with Con-IS. The maintenance MD3 group (MA-MD3, n = 4) received MD3 for 3 months, monthly doses by 2 years, and then quarterly. The MA-MD3 group exhibited stable liver function without overt infection and had significantly better liver allograft survival than the IN-MD3 group. Development of donor-specific antibody and chronic rejection were suppressed in the MA-MD3 group but not in the IN-MD3 group. Donor-specific T cell responses were attenuated in the MA-MD3 group. In conclusion, MD3 monomaintenance therapy without maintenance CNI provides long-term liver allograft survival by suppressing chronic rejection, offering a potential breakthrough for future human trials.

Management of Tacrolimus-Induced Toxicity With Normal Serum Levels After Liver Transplant

Drug-induced liver injury after liver transplant occurs in 1.7% of patients. Tacrolimus is an effective immunosuppressant that is used to treat acute rejection. Although rare, it can cause toxicity, which is demonstrated by cholestatic liver injury. Here, we present a case of a young male patient who was diagnosed with Wilson disease, had penicillaminechelating therapy, and underwent living related liver transplant. Within 1 month posttransplant, he developed deranged, predominantly cholestatic pattern liver function tests. Laboratory parameters showed total bilirubin of 1.12 mg/ dL, alanine aminotransferase of 553 IU/L, gammaglutamyltransferase of 624 IU/L, and tacrolimus level of 10.2 ng/mL. After thorough evaluation, a liver biopsy was performed. Liver biopsy showed hepatocellular necrosis with centrilobular cholestasis without any evidence of graft rejection. However, with normal level of tacrolimus, the biopsy was suggestive of drug-induced liver injury. Thus, tacrolimus dose was reduced, resulting in improved liver function tests and patient discharge from the hospital. Tacrolimus is an effective immunosuppressant after liver transplant and has the ability to treat early acute rejection. The patient's liver biopsy showed hepatocellular necrosis with centrilobular cholestasis without any evidence of graft rejection. Cholestatic liver injury after tacrolimus usually resolves after dose reduction or by switching to another agent. With demonstrated tacrolimus-induced toxicity in liver transplant recipients, despite normal serum levels, transplant physicians should keep high index of suspicion regarding toxicity in the posttransplant setting.

Delayed-Onset Psychosis Secondary to Tacrolimus Neurotoxicity After Lung Transplant: A Case Report and Systematic Review

BACKGROUND

Tacrolimus is the most common immunosuppressant used after transplant, yet it can result in moderate-to-severe neurotoxicity in up to 32% of patients. Signs of neurotoxicity can vary from mild (tremor or headache) to severe (posterior reversible encephalopathy syndrome or psychosis. Prompt recognition and management is needed to lead to symptom resolution.

OBJECTIVE

The objective of this study is to describe the clinical presentation of tacrolimus-induced psychosis, a type of tacrolimus-inducted neurotoxicity, and distinguish it from other central nervous system disturbances, including delirium.

METHODS AND RESULTS

We present a case of delayed onset tacrolimus-induced psychosis with focus on unique clinical features and management strategies. We conducted a systematic review of cases of tacrolimus-induced psychosis using the PubMed database and included 15 manuscripts in our review.

CONCLUSIONS

Tacrolimus-induced psychosis is a unique presentation of tacrolimus-related neurotoxicity and can present without the cardinal symptoms of delirium. The data on isolated psychotic symptoms are limited with current literature focusing on more common presentations of tacrolimus-induced neurotoxicity, such as delirium and tremor. Development of psychosis can occur later in the treatment course and at normal tacrolimus serum levels. It can improve with antipsychotic therapies, but primary management should include cross-titration to an alternate immunosuppressant regimen.

Sustained Release of Tacrolimus Embedded in a Mixed Thermosensitive Hydrogel for Improving Functional Recovery of Injured Peripheral Nerves in Extremities

Vascularized composite allotransplantation is an emerging strategy for the reconstruction of unique defects such as amputated limbs that cannot be repaired with autologous tissues. In order to ensure the function of transplanted limbs, the functional recovery of the anastomosed peripheral nerves must be confirmed. The immunosuppressive drug, tacrolimus, has been reported to promote nerve recovery in animal models. However, its repeated dosing comes with risks of systemic malignancies and opportunistic infections. Therefore, drug delivery approaches for locally sustained release can be designed to overcome this issue and reduce systemic complications. We developed a mixed thermosensitive hydrogel (poloxamer (PLX)-poly(l-alanine-lysine with Pluronic F-127) for the time-dependent sustained release of tacrolimus in our previous study. In this study, we demonstrated that the hydrogel drug degraded in a sustained manner and locally released tacrolimus in mice over one month without affecting the systemic immunity. The hydrogel drug significantly improved the functional recovery of injured sciatic nerves as assessed using five-toe spread and video gait analysis. Neuroregeneration was validated in hydrogel-drug-treated mice using axonal analysis. The hydrogel drug did not cause adverse effects in the mouse model during long-term follow-up. The local injection of encapsulated-tacrolimus mixed thermosensitive hydrogel accelerated peripheral nerve recovery without systemic adverse effects.

Tacrolimus-Eluting Disk within the Allograft Enables Vascularized Composite Allograft Survival with Site-Specific Immunosuppression without Systemic Toxicity

AIM

Widespread clinical application of vascularized composite allotransplantation (VCA) has been limited by the need for lifelong systemic immunosuppression to prevent rejection. Our goal was to develop a site-specific immunosuppressive strategy that promotes VCA allograft survival and minimizes the risk of systemic side effects.

METHODS

Tacrolimus loaded polycaprolactone (TAC-PCL) disks were prepared and tested for their efficacy in sustaining VCA allograft survival via site-specific immunosuppression. Brown Norway-to-Lewis rat hind limb transplantations were performed; animals received one TAC disk either in the transplanted (DTx) or in the contralateral non-transplanted (DnonTx) limbs. In another group, animals received DTx and lymphadenectomy on Tx side. Blood and allograft levels of TAC were measured using LC-MS/MS. Systemic toxicity was evaluated.

RESULTS

Animals that received DTx achieved long-term allograft survival (> 200 days) without signs of metabolic and infectious complications. In these animals, TAC blood levels were low but stable between 2 to 5 ng/mL for nearly 100 days. High concentrations of TAC were achieved in the allografts and the draining lymph nodes (DLN). Animals that underwent lymphadenectomy rejected their allograft by 175 days. Animals that received DnonTx rejected their allografts by day 70.

CONCLUSION

Controlled delivery of TAC directly within the allograft (with a single TAC disk) effectively inhibits rejection and prolongs VCA allograft survival, while mitigating the complications of systemic immunosuppression. There was a survival benefit of delivering TAC within the allograft as compared to a remote site. We believe this approach of local drug delivery has significant implications for drug administration in transplantation.

The use of tacrolimus in the management of checkpoint inhibitor immunotherapy-induced hepatitis

Immune-mediated hepatitis is recognised as a frequently occurring complication with the use of checkpoint inhibitor immunotherapy drugs. The mainstay of treatment involves the use of immunosuppressive agents, such as corticosteroids. Mycophenolate mofetil is added when steroid resistant. However, there are limited data to guide further management when the hepatitis remains refractory to these therapies. We present two patients who developed severe immunotherapy-induced hepatitis and required prolonged immunosuppressive therapy with three agents in combination before resolution was achieved. We demonstrate that the addition of tacrolimus can be successful when other drugs fail. We also illustrate how a subsequent wean off immunosuppression can be safely performed and highlight the use of concordant antimicrobial prophylaxis to mitigate against opportunistic infections.

Population pharmacokinetics and dosage optimization of tacrolimus coadministration with Wuzhi capsule in adult liver transplant patients

1. This study aimed to establish a population pharmacokinetic model of tacrolimus coadministration with Wuzhi capsule and optimize the dosage regimen in adult liver transplant patients.2. Totally 1327 tacrolimus trough concentrations from 116 adult liver transplant patients were obtained for model development. A one-compartment model with first-order absorption and elimination was used to analyse the data, and the final model was internally verified using a goodness-of-fit diagnostic plot, bootstrap methods, and visual prediction test. A total of 29 patients with 250 tacrolimus trough concentrations was used for external validation via prediction-based diagnostics. Additionally, the simulation was used to optimize the recommended dose of tacrolimus and Wuzhi capsules.3. The estimated apparent clearance and volume of the distribution of tacrolimus were 15.4 L/h and 1210 L, respectively. The tacrolimus daily dose, Wuzhi capsule daily dose, postoperative time, alanine transaminase, haemoglobin, total bilirubin, direct bilirubin, estimated glomerular filtration rate, and urea, concomitant with voriconazole and fluconazole, were identified as significant covariates affecting the pharmacokinetic parameters. Internal and external validation showed that the final model was stable and reliable for predicting performance.4. The final model could provide guidance for dosage optimization of tacrolimus coadministered with Wuzhi capsules in adult liver transplantation patients.

New-Onset Diabetes Mellitus (NODM) After Liver Transplantation (LT): The Ultimate Non-diabetogenic Immunosuppressive Therapy

New-onset diabetes mellitus (NODM) is a common long-term complication after liver transplantation (LT). It is thought to be drug-induced in most cases, no matter the underlying disease that cause liver failure and indicated transplantation. Standard post-transplantation (PT) immunosuppressive regimens include prolonged use of calcineurin inhibitors (CNIs), namely tacrolimus (TAC), alongside corticosteroids to avoid acute and chronic graft rejection. This combination is well known for its diabetogenicity. Significant differences between the applied regimens stand out concerning the duration and dosages to prevent the metabolic side effects of these drugs in the long run without compromising the graft's survival. Studies were collected after an extensive research of PubMed database for this very specific topic using the following MeSH keywords in multiple combinations: "Liver Transplantation," "Diabetes Mellitus," "NODM," "Tacrolimus," "Cyclosporine A," and "Steroids." In addition, we used the same keywords for regular searches in Google Scholar. Only the relevant English human studies between 2010 and 2020 were collected except for review articles. Duplicates were eliminated using Mendeley software. Twelve relevant studies directly related to the targeted topic were collected and discussed, including five retrospective cohorts, four prospective cohorts, one clinical trial, one prospective pilot, and one case report. Their topics included primarily the factors increasing the risk of new-onset diabetes mellitus after liver transplantation (NODALT), TAC-based immunosuppression and its relative blood levels affecting the possible development of NODALT, the role of cyclosporine in substituting TAC regimen, and the effect of different steroids-avoiding protocols on the prevention of NODALT. The reviewed studies suggested that lowering the serum concentration of tacrolimus (cTAC) throughout the PT period and eliminating the corticosteroids regimen as early as possible, among other measures, can significantly impact the rate of emergence of NODM. This traditional review tackles the most recent studies about NODALT to establish a comprehensive view on this issue and guide clinicians and researchers for the safest immunosuppressive regimen to date, while maintaining a balanced metabolic profile.

Possible Tacrolimus-Related Neuropsychiatric Symptoms: One Year After Allogeneic Hematopoietic Cell Transplantation: A Case Report

Tacrolimus is a calcineurin inhibitor (CNI), an immunosuppressive agent used to prevent graft versus host disease following allogeneic hematopoietic cell transplantation (HCT). Side-effects of tacrolimus treatment include neuropsychiatric symptoms, for example, affective disturbances, psychosis, and akinetic mutism. The onset of side-effects is independent of tacrolimus blood concentration and can occur years after treatment initiation. To our knowledge, case-reports describing tacrolimus-induced neuropsychiatric symptoms following HCT are sparse. This article reports the case of a 60-year-old woman with T-cell prolymphocytic leukemia, who developed memory loss, affective disturbances, and delusions, 1-year after HCT, and tacrolimus treatmentinitiation. Upon hospital admission, she was motionless and mute, albeit easily roused. The routine physical examination was without pathological findings. Blood work and microbiological analyses of blood and cerebrospinal fluid were normal. The neuroimaging showed chronic structural changes without relation to the debut of neuropsychiatric symptoms. Tacrolimus was discontinued on suspicion of tacrolimus-induced neuropsychiatric symptoms. The patient recovered within 48 hours of discontinuation. She was switch to prednisone treatment, and there has been no reemergence of neuropsychiatric symptoms since.

Can We Predict Individual Concentrations of Tacrolimus After Liver Transplantation? Application and Tweaking of a Published Population Pharmacokinetic Model in Clinical Practice

BACKGROUND

Various population pharmacokinetic models have been developed to describe the pharmacokinetics of tacrolimus in adult liver transplantation. However, their extrapolated predictive performance remains unclear in clinical practice. The purpose of this study was to predict concentrations using a selected literature model and to improve these predictions by tweaking the model with a subset of the target population.

METHODS

A literature review was conducted to select an adequate population pharmacokinetic model (L). Pharmacokinetic data from therapeutic drug monitoring of tacrolimus in liver-transplanted adults were retrospectively collected. A subset of these data (70%) was exploited to tweak the L-model using the $PRIOR subroutine of the NONMEM software, with 2 strategies to weight the prior information: full informative (F) and optimized (O). An external evaluation was performed on the remaining data; bias and imprecision were evaluated for predictions a priori and Bayesian forecasting.

RESULTS

Seventy-nine patients (851 concentrations) were enrolled in the study. The predictive performance of L-model was insufficient for a priori predictions, whereas it was acceptable with Bayesian forecasting, from the third prediction (ie, with ≥2 previously observed concentrations), corresponding to 1 week after transplantation. Overall, the tweaked models showed a better predictive ability than the L-model. The bias of a priori predictions was -41% with the literature model versus -28.5% and -8.73% with tweaked F and O models, respectively. The imprecision was 45.4% with the literature model versus 38.0% and 39.2% with tweaked F and O models, respectively. For Bayesian predictions, whatever the forecasting state, the tweaked models tend to obtain better results.

CONCLUSIONS

A pharmacokinetic model can be used, and to improve the predictive performance, tweaking the literature model with the $PRIOR approach allows to obtain better predictions.

Functional Improvement of Tacrolimus-Induced Parkinsonism With Amantadine After Liver Transplantation: A Case Report

ABSTRACT

Drug-induced parkinsonism is the most common type of drug-induced movement disorder, whose symptoms can decrease patient quality of life and reduce medication compliance. Tacrolimus is a routinely used immunosuppressant agent after liver transplantation, with a well-known neurotoxic profile. There have been rare reports of tacrolimus-induced parkinsonism, but its pharmacologic management and functional impact remain poorly characterized in the literature. We present a case of tacrolimus-induced parkinsonism in a 62-year-old man after a liver transplant, resulting in significant neurologic impairments and multiple barriers to hospital discharge. His tremor, rigidity, bradykinesia, gait dysfunction, dysphonia, and dysphagia significantly improved after starting low-dose amantadine, with increased functional independence that allowed for a safe discharge. This is the first case in the literature detailing tacrolimus-induced parkinsonism's functional impairments improving with amantadine monotherapy.

A Time-Based Meta-Analysis on the Incidence of New Onset Diabetes after Liver Transplantation

NODAT (new-onset diabetes after transplantation) is an important complication after liver transplant, however, there is variation in the reported incidence of NODAT. Therefore, a meta-analysis was performed to estimate the incidence of NODAT in liver transplant. Electronic databases were searched for articles regarding NODAT incidence after liver transplantation. Incidence of NODAT were analyzed at six different timepoints. Summary statistics were calculated using a generalized linear mixed model in random effects. 28 articles were included and out of a pooled population of 71,257 patients, overall incidence of NODAT was found to be 15.51%, 16.09%, 18.30%, 20.86%, 18.08%, 25.05% for three-months, six-months, one-year, three-year, five-year, and ten-year timepoints respectively. After a sensitivity analysis which only included articles with clear definitions of NODAT, the incidence of NODAT was found to be higher at three-year (21.79%), five-year (25.82%), and ten-year (44.95%) timepoints. Subgroup analysis according to ethnicity found no significant differences for all timepoints. However, studies with predominantly Asian participants generally had a higher incidence of NODAT. In conclusion, this meta-analysis provides a pooled estimate of the incidence of NODAT following liver transplantation. Further studies are required to provide a more comprehensive understanding on how ethnicity can affect the incidence of NODAT.

Neurologic Toxicities Associated with Tumor Necrosis Factor Inhibitors and Calcineurin Inhibitors

The calcineurin inhibitors cyclosporine and tacrolimus are used for their immunosuppressive effects. Neurotoxic side effects include tremor, paresthesia, and headache. Rarer neurotoxicities include seizure, posterior reversible encephalopathy syndrome, and encephalopathy. Tacrolimus tends to be more neurotoxic than cyclosporine. Management of toxicities associated with calcineurin inhibitors includes dose reduction, switching between calcineurin inhibitors, or switching to a calcineurin-free regimen. Tumor necrosis factor (TNF) inhibitors are used in autoimmune diseases. Management of demyelinating conditions among patients treated with anti-TNF should follow standard of care and withdrawal of the anti-TNF. This drug class should be avoided in patients with a history of demyelinating conditions.

Factors Associated With Neurobehavioral Complications in Pediatric Abdominal Organ Transplant Recipients Identified Using Computable Composite Definitions

OBJECTIVES

Neurologic complications occur in up to 40% of adult abdominal solid organ transplant recipients and are associated with increased mortality. Comparable pediatric data are sparse. This study describes the occurrence of neurologic and behavioral complications (neurobehavioral complications) in pediatric abdominal solid organ transplant recipients. We examine the association of these complications with length of stay, mortality, and tacrolimus levels.

DESIGN

The electronic health record was interrogated for inpatient readmissions of pediatric abdominal solid organ transplant recipients from 2009 to 2017. A computable composite definition of neurobehavioral complication, defined using structured electronic data for neurologic and/or behavioral phenotypes, was created.

SETTING

Quaternary children's hospital with an active transplant program.

PATIENTS

Pediatric abdominal solid organ transplant recipients.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Computable phenotypes demonstrated a specificity 98.7% and sensitivity of 63.0% for identifying neurobehavioral complications. There were 1,542 readmissions among 318 patients, with 65 (20.4%) having at least one admission with a neurobehavioral complication (total 109 admissions). Median time from transplant to admission with neurobehavioral complication was 1.2 years (interquartile range, 0.52-2.28 yr). Compared to encounters without an identified neurobehavioral complication, encounters with a neurobehavioral complication were more likely to experience ICU admission (odds ratio, 3.9; 2.41-6.64; p < 0.001), have longer ICU length of stay (median 10.3 vs 2.2 d; p < 0.001) and hospital length of stay (8.9 vs 4.3 d; p < 0.001), and demonstrate higher maximum tacrolimus level (12.3 vs 9.8 ng/mL; p = 0.001). Patients with a neurobehavioral complication admission were more likely to die (odds ratio, 5.04; 1.49-17.09; p = 0.009). In a multivariable analysis, type of transplant, ICU admission, and tacrolimus levels were independently associated with the presence of a neurobehavioral complication.

CONCLUSIONS

Common electronic health record variables can be used to accurately identify neurobehavioral complications in the pediatric abdominal solid organ transplant population. Late neurobehavioral complications are associated with increased hospital resource utilization, mortality, and tacrolimus exposure. Additional studies are required to delineate the relationship between maximum tacrolimus level and neurobehavioral complications to guide therapeutic drug monitoring and dosing.

Maintenance Immunosuppression in Solid Organ Transplantation: Integrating Novel Pharmacodynamic Biomarkers to Inform Calcineurin Inhibitor Dose Selection

Calcineurin inhibitors, the primary immunosuppressive therapy used to prevent alloreactivity of transplanted organs, have a narrow therapeutic index. Currently, treatment is individualized based on clinical assessment of the risk of rejection or toxicity guided by trough concentration monitoring. Advances in immune monitoring have identified potential markers that may have value in understanding calcineurin inhibitor pharmacodynamics. Integration of these markers has the potential to complement therapeutic drug monitoring. Existing pharmacokinetic-pharmacodynamic (PK-PD) data is largely limited to correlation between the biomarker and trough concentrations at single time points. Immune related gene expression currently has the most evidence supporting PK-PD integration. Novel biomarker-based approaches to pharmacodynamic monitoring including development of enhanced PK-PD models are proposed to realize the full clinical benefit.

A randomized clinical trial of age and genotype-guided tacrolimus dosing after pediatric solid organ transplantation

BACKGROUND

Tacrolimus pharmacokinetics are influenced by age and CYP3A5 genotype with CYP3A5 expressors (CYP3A5*1/*1 or *1/*3) being fast metabolizers. However, the benefit of genotype-guided dosing in pediatric solid organ transplantation has been understudied.

OBJECTIVE

To determine whether age and CYP3A5 genotype-guided starting dose of tacrolimus result in earlier attainment of therapeutic drug concentrations.

SETTING

Single hospital-based transplant center.

METHODS

This was a randomized, semi-blinded, 30-day pilot trial. Between 2012 and 2016, pediatric patients listed for solid organ transplant were consented and enrolled into the study. Participants were categorized as expressors, CYP3A5*1/*1 or CYP3A5*1/*3, and nonexpressors, CYP3A5*3/*3. Patients were stratified by age (≤ or > 6 years) and randomized (2:1) after transplant to receive genotype-guided (n = 35) or standard (n = 18) starting dose of tacrolimus for 36-48 hours and were followed for 30 days.

RESULTS

Median age at transplant in the randomized cohort was 2.1 (0.75-8.0) years; 24 (45%) were male. Participants in the genotype-guided arm achieved therapeutic concentrations earlier at a median (IQR) of 3.4 (2.5-6.6) days compared to those in the standard dosing arm of 4.7 (3.5-8.6) days (P = 0.049), and had fewer out-of-range concentrations [OR (95% CI) = 0.60 (0.44, 0.83), P = 0.002] compared to standard dosing, with no difference in frequency of adverse events between the two groups.

CONCLUSIONS

CYP3A5 genotype-guided dosing stratified by age resulted in earlier attainment of therapeutic tacrolimus concentrations and fewer out-of-range concentrations.

An Elastomeric Polymer Matrix, PEUU-Tac, Delivers Bioactive Tacrolimus Transdurally to the CNS in Rat

Central nervous system (CNS) neurons fail to regrow injured axons, often resulting in permanently lost neurologic function. Tacrolimus is an FDA-approved immunosuppressive drug with known neuroprotective and neuroregenerative properties in the CNS. However, tacrolimus is typically administered systemically and blood levels required to effectively treat CNS injuries can lead to lethal, off-target organ toxicity. Thus, delivering tacrolimus locally to CNS tissues may provide therapeutic control over tacrolimus levels in CNS tissues while minimizing off-target toxicity. Herein we show an electrospun poly(ester urethane) urea and tacrolimus elastomeric matrix (PEUU-Tac) can deliver tacrolimus trans-durally to CNS tissues. In an acute CNS ischemia model in rat, the optic nerve (ON) was clamped for 10s and then PEUU-Tac was used as an ON wrap and sutured around the injury site. Tacrolimus was detected in PEUU-Tac wrapped ONs at 24 h and 14 days, without significant increases in tacrolimus blood levels. Similar to systemically administered tacrolimus, PEUU-Tac locally decreased glial fibrillary acidic protein (GFAP) at the injury site and increased growth associated protein-43 (GAP-43) expression in ischemic ONs from the globe to the chiasm, consistent with decreased astrogliosis and increased retinal ganglion cell (RGC) axon growth signaling pathways. These initial results suggest PEUU-Tac is a biocompatible elastic matrix that delivers bioactive tacrolimus trans-durally to CNS tissues without significantly increasing tacrolimus blood levels and off-target toxicity.

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PEUU-Tac locally delivers tacrolimus to CNS tissues

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PEUU-Tac positively modulates CNS tissue remodeling

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PEUU-Tac minimizes off-target tacrolimus toxicity

Central nervous system (CNS) injury typically results in permanently lost neurological function. Tacrolimus is an FDA-approved drug used during organ transplantation that also has CNS neuroprotective and neuroregenerative properties. However, tacrolimus is typically delivered systemically in the blood and delivering effective concentrations to CNS tissues requires tacrolimus blood levels that can lead to adverse side effects in multiple organs. Herein we show that PEUU-Tac, a tacrolimus-eluting matrix, can locally deliver tacrolimus to injured CNS tissues without increasing blood levels, suggesting PEUU-Tac can be used to treat CNS injuries locally while minimizing adverse side effects.

Cognitive Evaluation in Liver Transplant Patients Under Calcineurin Inhibitor Maintenance Therapy

BACKGROUND

Neurological disorders due to calcineurin inhibitor (CNI) treatment pose a well-known problem after liver transplantation (LTx). In this study, the impact of CNIs on cognitive functioning during maintenance therapy was analyzed. A possible improvement of cognitive functioning, compliance and health-related quality of life (HRQoL) after conversion to a once-daily tacrolimus formulation was prospectively assessed.

METHODS

In a cross-section analysis cognitive functioning of living donors (LD), waiting list patients and LTx patients was tested using a 4 times trail making test (4-TTMT). In a further investigator-initiated trial a possible improvement of cognitive functioning, HRQoL and compliance after conversion to the once-daily tacrolimus formulation was prospectively assessed over 1 year. HRQoL was assessed using an EORTC-QLQ C30 questionnaire and patient's compliance was assessed by the Basel Assessment of Compliance with Immunosuppressive Medication Scales questionnaire. Correlated data were sex, age, time after surgery, liver disease, model of end-stage liver disease score, creatinine, CNI type, and CNI trough levels.

RESULTS

Two hundred eleven patients were included in this cross-section analysis. Twenty-seven patients agreed to participate in the investigator-initiated trial. LTx patients completed the 4-TTMT slower than living donor patients and faster than waiting list patients. Patients with twice daily cyclosporine A (CSA) formulation needed longer to finish the 4-TTMT than patients with the once-daily tacrolimus formulation. After drug conversion of a twice-daily CNI formulation to a once-daily tacrolimus formulation, CSA-treated patients needed longer to improve their cognitive functioning. HRQoL and compliance did not improve after drug conversion.

CONCLUSIONS

Patients with once-daily tacrolimus formulation had a better psychomotor speed than CSA-treated patients. The conversion to once-daily tacrolimus formulation significantly improved cognitive functioning, but had no impact on HRQoL or compliance.

Evaluating tacrolimus treatment in idiopathic membranous nephropathy in a cohort of 408 patients

BACKGROUND

The KDIGO Clinical Practice Guidelines for Glomerulonephritis recommended tacrolimus as an alternative regimen for the initial therapy for Idiopathic membranous nephropathy (IMN), however, large observational studies evaluating tacrolimus treatment in IMN remains rare.

METHODS

A total of 408 consecutive IMN patients with nephrotic syndrome who were treated with tacrolimus in Jinling Hospital were included. The effectiveness and safety of tacrolimus treatment in IMN were analyzed in this study.

RESULTS

The cumulative partial or complete remission after tacrolimus therapy were 50%, 63% and 67% at 6, 12 and 24 months, respectively, and the cumulative complete remission rates were 4%, 13% and 23%, respectively. Multivariate logistic analysis showed that higher tacrolimus exposure during induction treatment, female gender, higher eGFR and no history of previous immunosuppressive therapy were independently associated with higher probability of remission. A relapse occurred in 101 of the 271 (37.3%) patients with partial or complete remission, and 18 of the 95 (18.9%) patients with complete remission. Tapering duration of tacrolimus and complete remission versus partial remission status were independent factors associated with risk of relapse. A decline in eGFR was the most frequent adverse event during tacrolimus treatment. During tacrolimus treatment, a ≥40% decrease in eGFR was observed in 43 (10.5%) patients.

CONCLUSIONS

Low dose tacrolimus is effective for IMN, with a total remission rate of 66% whereas with a rather high rate of relapse. However, the safety of tacrolimus treatment needs to be further validated in large randomized clinical trials.

The Comparative Safety of Multiple Alternative Agents in Refractory Chronic Urticaria Patients

BACKGROUND

Patients who have failed traditional treatment of chronic urticaria may require trials of alternative medications. Safety profiles, continuous laboratory monitoring, and physician comfort are often barriers to treatment.

OBJECTIVES

To evaluate the safety of alternative agents used in chronic urticaria.

METHODS

A retrospective chart review of electronic medical records from a single-center allergy and immunology clinic in a major academic hospital was conducted. One hundred twenty-six charts of patients with chronic urticaria treated with alternative agents were reviewed.

RESULTS

Adverse effects were reported in 39 of 73 (53%) patients on dapsone, 19 of 47 (40%) patients on sulfasalazine, 15 of 36 (42%) patients on tacrolimus, 7 of 45 (16%) patients on hydroxychloroquine, 9 of 27 (33%) patients on mycophenolate, 6 of 8 (75%) patients on cyclosporine, and 3 of 24 (4%) patients on omalizumab. Most of these adverse effects were mild, did not require discontinuation of the medication, and resolved after stopping the medication or decreasing the dose.

CONCLUSIONS

The use of alternative agents for the treatment of chronic urticaria angioedema is generally safe when proper laboratory and clinical monitoring is observed.

Living donor liver transplantation in India

Liver transplantation is currently in its golden period in India. The number of transplants being performed and the steady increase in the new programs that have emerged over the last decade is a testimony to it. The growth was not smooth, especially in the early years. But a multipronged approach in developing infrastructure and the involvement of multidisciplinary teams in the management of transplant patients has had a major positive impact on the outcome and as a result a positive impetus to the growth of this specialty in India. To date, the majority of transplants performed in India are live donor liver transplants. Deceased donation is more sporadic and concentrated in a couple of regions. With phenomenal increase in transplant activity in India, there is huge potential for streamlining data sharing among programs in India and with the rest of the world to ultimately benefit the transplant community.

New-Onset Diabetes Mellitus in Liver Transplant Recipients With Hepatitis C: Analysis of the National Database

BACKGROUND

New-onset diabetes mellitus (NODM) after liver transplantation (LT) occurs with increased frequency in recipients with hepatitis C virus (HCV). We compared the incidence and risk factors for NODM in HCV vs non-HCV recipients.

METHODS

Among 24,956 liver recipients, 18,741 without pretransplantation diabetes were identified. NODM-free survival was analyzed using Kaplan-Meier and log-rank tests, and risk factors for NODM were examined using multivariate Cox regression analysis.

RESULTS

The overall incidence of NODM was 13.0% at 1 year after LT. At 1, 2, 3, and 5 years after LT, incidence of NODM in HCV recipients was 14.4%, 4.3%, 3.1%, and 3.5%, respectively, compared with 11.9%, 3.5%, 3.2%, and 6.4%, respectively, in non-HCV recipients. HCV recipients had a higher risk of NODM than non-HCV recipients (hazard ratio 1.17 [1.09-1.27], P < .001). Predictors of NODM in HCV recipients were age, body mass index (BMI), tacrolimus and steroid usage at discharge, acute rejection episode, and donor with diabetes mellitus. Risk factors in non-HCV recipients were male recipient, BMI, and recipients with nonalcoholic steatohepatitis diagnosis.

CONCLUSIONS

HCV recipients have a higher incidence and more risk factors for NODM than non-HCV recipients. Early identification of modifiable risk factors will assist clinical interventions to prevent NODM complications after LT.

An integrated microfluidic device for screening the effective concentration of locally applied tacrolimus for peripheral nerve regeneration

The effectiveness of tacrolimus (FK506) for the promotion of nerve regeneration is known. However, at present, due to the fact that systemic application may lead to opportunistic infections and tumors, and that the treatment of peripheral nerve injury with systemic immunosuppression is not generally accepted, FK506 has not been widely used for the treatment of simple or peripheral nerve injury. In this study, a pyramid-shaped microfluidic device was designed and fabricated that was able to analyze the effective concentration of locally applied FK506. After testing the effectiveness of the microfluidic device by measuring the fluorescence intensity of fluorescein isothiocyanate-dextran, rat Schwann cells (SCs) were loaded into the device and cultured for 9 days in the presence of different concentrations of FK506. SC proliferation in the presence of FK506 was concentration-dependent between 0 and 2.5±0.003 ng/ml. The proliferation rate reached a maximum at 1.786±0.014 ng/ml, which was statistically significantly different from the proliferation rate at lower FK506 concentrations. There was no statistically significant difference in the proliferation rate between the 1.786 ng/ml group and groups of higher FK506 concentrations. Furthermore, the SCs in the microfluidic device and a 96-well plate continued to proliferate as the culture time increased. No statistically significant differences were identified between the microfluidic device and a 96-well plate with regard to the proliferation rates in each corresponding group. The results obtained in this study demonstrated that the microfluidic device can be used as an excellent platform for the study of drug concentration at the cellular level, and the effective FK506 concentration for local application is 1.786±0.014 ng/ml.

An analysis of tacrolimus-related complications in the first 30 days after liver transplantation

OBJECTIVES

Orthotopic liver transplantation has improved survival in patients with end-stage liver disease; however, therapeutic strategies that achieve ideal immunosuppression and avoid early complications are lacking. To correlate the dose and level of Tacrolimus with early complications, e.g., rejection, infection and renal impairment, after liver transplantation. From November 2011 to May 2013, 44 adult liver transplant recipients were studied in this retrospective comparative study.

RESULTS

The most frequent indication for liver transplantation was hepatitis C cirrhosis (47.7%), with a higher prevalence observed in male patients (68.18%). The ages of the subjects ranged from 19-71 and the median age was 55.5 years. The mean length of the hospital stay was 16.1±9.32 days and the mean Model for End-stage Liver Disease score was 26.18±4.28. There were five cases of acute cellular rejection (11.37%) and 16 cases of infection (36.37%). The blood samples that were collected and analyzed over time showed a significant correlation between the Tacrolimus blood level and the deterioration of glomerular filtration rate and serum creatinine (p<0.05). Patients with infections had a higher serum level of Tacrolimus (p = 0.012). The dose and presence of rejection were significantly different (p = 0.048) and the mean glomerular filtration rate was impaired in patients who underwent rejection compared with patients who did not undergo rejection (p = 0.0084).

CONCLUSION

Blood Tacrolimus levels greater than 10 ng/ml were correlated with impaired renal function. Doses greater than 0.15 mg/kg/day were associated with the prevention of acute cellular rejection but predisposed patients to infectious disease.