Clinical Experience with Extended-Release Tacrolimus in Older Adult Kidney Transplant Recipients: A Retrospective Cohort Study

HDL-C and creatinine levels at 1 month are associated with patient 12-month survival rate after kidney transplantation

BACKGROUND

Many factors affect the survival rate after kidney transplantation, including laboratory tests, medicine therapy and pharmacogenomics. Tacrolimus, mycophenolate mofetil and methylprednisolone were used as an immunosuppressive regimen after kidney transplantation. The primary goal of this study was to investigate the factors affecting the tacrolimus concentrations and mycophenolate mofetil area under the curve of mycophenolic acid AUC-MPA. Secondary goals were to study the association between perioperative period laboratory tests, medicine therapy, CYP3A5 genetic polymorphisms, and survival rate in kidney renal transplant patients.

METHODS

A total of 303 patients aged above 18 years were enrolled in this study. Their clinical characteristics, laboratory tests, and medicine therapy regimens were collected. We followed the patients for survival for 1 year after kidney transplantation.

RESULTS

Multivariable logistic analyses reveal that age greater than 50 years, and the CY3A5 *3*3 genotype were independently, positively, and significantly related to tacrolimus C/D ratio at 7 days. At 1 month of follow-up, only CYP3A5 *3*3 was associated with tacrolimus C/D ratio. Basiliximab, Imipenem and cilastatin sodium, sex were associated with mycophenolate mofetil AUC-MPA at 7 days. In the COX regression analysis, a high-density lipoprotein cholesterol level≥1 mmol/L was identified as a positive independent risk factors for the survival rate, while a creatinine level ≥200 μmol/L was a negatively independent risk factors for survival rate.

CONCLUSION

These results suggest that age, genes, and drug-drug interaction can affect the concentration of tacrolimus.

The association between tacrolimus exposure and tremor, headache and insomnia in adult kidney transplant recipients: A systematic review

PURPOSE

Tremor, headache and insomnia have been linked to the immunosuppressant, tacrolimus. The aim of this systematic review was to determine if there is a correlation between tacrolimus exposure and new-onset tremor, headache and insomnia experienced by adult kidney transplant recipients.

METHODS

PubMed, Embase, Cochrane Library and CINAHL databases were searched up to 11 April 2023 for published studies which reported on tacrolimus exposure in adult kidney transplant recipients, alongside information on treatment-emergent neurologic manifestations, including tremor, headache and insomnia. Review articles, case studies, conference abstracts and articles not published in English in peer-reviewed journals were excluded. The Physiotherapy Evidence Database and Newcastle-Ottawa Quality Assessment Scales were used to assess risk of bias. Extracted data was analysed via a narrative synthesis.

RESULTS

Eighteen studies involving 4030 patients in total were included in the final analysis. These comprised five randomised control trials and thirteen observational studies. Studies failed to find significant association between tacrolimus trough concentrations in whole blood and the incidence of neurologic side effects such as tremor, headache and insomnia; however, in one study the incidence of toxicity requiring a dose reduction increased with increasing, supratherapeutic targeted levels. Females, especially Black females, and older age were positively associated with the prevalence of neurologic adverse effects. Results were conflicting regarding whether extended-release formulations were associated with fewer neurologic complications than immediate-release formulations.

CONCLUSION

The varied study designs and criteria for reporting tremor, headache and insomnia impacted on the quality of the data for exploring the relationship between tacrolimus exposure and the onset of neurologic manifestations experienced after kidney transplantation. Studies that examine defined neurologic complications as the primary outcome, and that consider novel markers of tacrolimus exposure while assessing the potential contribution of multiple covariate factors, are required.

Tremor Induced by Cyclosporine, Tacrolimus, Sirolimus, or Everolimus: A Review of the Literature

Calcineurin inhibitors such as cyclosporine and tacrolimus are immunosuppressant drugs that are known to induce tremors. Non-calcineurin inhibitors such as sirolimus and everolimus have also reportedly been accompanied by tremors, albeit less likely. However, the prevalence rates reported in the literature are notably wide, and the risk profiles for these drug-induced tremors are less understood. We searched PubMed to extract data on the risk of tremors with these drugs when prescribed for various transplant and non-transplant indications. We ascertained whether the risk of drug-induced tremor is influenced by the underlying diagnosis, dosing formulations, drug concentrations, and blood monitoring. We extracted data on treatment strategies and outcomes for tremors. Articles were primarily screened based on English language publications, abstracts, and studies with n ≥ 5, which included case series, retrospective studies, case-controlled studies, and prospective studies. We found 81 eligible studies comprising 33 cyclosporine, 43 tacrolimus, 6 sirolimus, and 1 everolimus that discussed tremor as an adverse event. In the pooled analysis of studies with n > 100, the incidence of tremor was 17% with cyclosporine, 21.5% with tacrolimus, and 7.8% with sirolimus and everolimus together. Regarding the underlying diagnosis, tremor was more frequently reported in kidney transplant (cyclosporine 28%, tacrolimus 30.1%) and bone marrow transplant (cyclosporine 40%, tacrolimus 41.9%) patients compared with liver transplant (cyclosporine 9%, tacrolimus 11.5%) and nontransplant indications (cyclosporine 21.5%, tacrolimus 11.3%). Most studies did not report whether the risk of tremors correlated with drug concentrations in the blood. The prevalence of tremors when using the twice-daily formulation of tacrolimus was nearly the same as the once-daily formulation (17% vs 18%). Data on individual-level risk factors for tremors were lacking. Except for three studies that found some benefit to maintaining magnesium levels, there were minimal data on treatments and outcomes. A large body of data supports a substantive and wide prevalence of tremor resulting from tacrolimus use followed by cyclosporine, especially in patients receiving a kidney transplant. However, there is little reporting on the patient-related risk factors for tremor, risk relationship with drug concentrations, treatment strategies, and outcomes.

Diabetes is a significant and independent predictor for tacrolimus immediate release and LCP-tacrolimus conversion ratios

Diabetes (DM) is a common comorbidity in transplant patients with known effects on gastrointestinal (GI) motility and absorption; however, DM's impact on immediate release (IR) tacrolimus to LCP-tacrolimus (LCP) conversion ratios has not been studied. This multivariable analysis of a retrospective longitudinal cohort study included kidney transplant recipients converted from IR to LCP between 2019 and 2020. The primary outcome was IR to LCP conversion ratio based on DM status. Other outcomes included tacrolimus variability, rejection, graft loss, and death. Of the 292 patients included, 172 patients had DM and 120 did not. The IR:LCP conversion ratio was significantly higher with DM (67.5% ± 21.1% no DM vs. 79.8% ± 28.7% in DM; P < .001). In multivariable modeling, DM was the only variable significantly and independently associated with IR:LCP conversion ratios. No difference was observed in rejection rates. Graft (97.5% no DM vs. 92.4% in DM; P = .062) and patient survival (100% no DM vs. 94.8% in DM; P = .011) were lower with DM. The presence of DM significantly increased the IR:LCP conversion ratio by 13%-14%, compared to patients without DM. On multivariable analysis, DM was the only significant predictor of conversion ratios, potentially related to GI motility or absorption differences.

Comparing the pharmacokinetics of extended-release tacrolimus (LCP-TAC) to immediate-release formulations in kidney transplant patients

INTRODUCTION

One of the most commonly used immunosuppressants in organ transplant, tacrolimus exhibits wide interpatient and intrapatient variability and narrow therapeutic index that necessitates routine concentration monitoring and dosage adjustments. Availability of modified -release tacrolimus products offer once-daily dosing options. The objective of this review is to highlight and compare available pharmacokinetic (PK) data of extended-release tacrolimus tablets (LCP-TAC) to immediate-release tacrolimus (IR-TAC) in kidney transplant recipients.

AREAS COVERED

A review of the literature was performed using PubMed and Embase search to identify relevant articles evaluating PK data for LCP-TAC compared to IR-TAC in kidney transplant patients including special populations.

EXPERT OPINION

LCP-TAC's unique PK profile may be more favorable than IR-TAC. While the clinical impact of these PK differences have not been established, several outcomes are being evaluated in ongoing studies. Results of these studies will add information incrementally to care for kidney transplant patients. Larger prospective studies evaluating kidney and patient survival differences are needed but it is unlikely that they will be conducted. Given that the patent exclusivity of LCP-TAC for the next several years and imminent loss of exclusivity of PR-TAC, our opinion is the use of LCP-TAC will be increasing, especially in Europe.