Sublingual tacrolimus administration provides similar drug exposure to per-oral route employing lower doses in liver transplantation: a pilot study

Sublingual Administration of Tacrolimus is Safe and Provides Similar Drug Exposure to Per-oral Route in Liver Transplant Recipients During Early Postoperative Period-A Large, Retrospective, Observational Study

Background/Aims

Per-oral (PO) administration of tacrolimus (TAC) results in inadequate trough levels in the early postoperative period in liver-transplant (LT) recipients who undergo Roux-en-Y hepaticojejunostomy for biliary reconstruction. Sublingual administration (SL) of tacrolimus provides an alternative route in such patients.The objectives of this study were to assess the feasibility and safety of SL tacrolimus in adult LT-recipients in the early postoperative period and to compare therapeutic efficacy of SL administration of tacrolimus versus PO route.

Methods

single-center, retrospective, observational study carried out in adult living donor liver transplant (LDLT) recipients between January 2022 and December 2022. Recipients who underwent Roux-en-Y hepaticojejunostomy for biliary reconstruction received tacrolimus through the SL route till postoperative day (POD) 5 as they were kept nil per oral constituted the study group while recipients who underwent duct-to-duct (D-D) anastomosis for biliary reconstruction were allowed orally from POD1 and received PO-tacrolimus were chosen as controls. The feasibility and safety of SL-tacrolimus were assessed in terms of patient acceptance, need to discontinue SL-tacrolimus, incidence of local adverse effects, and systemic adverse events like neurotoxicity and nephrotoxicity. Therapeutic efficacy was evaluated by comparing median trough levels (TAC level) achieved and incidence of graft rejection between two groups.

Results

Two hundred twelve patients underwent LT during the study period, of which 125 were included (58 in the SL-group and 67 in PO-group). Both groups had comparable baseline characteristics. In the SL-group, all patients tolerated SL-Tacrolimus well and no local adverse events were observed. Patients with SL-Tacrolimus administration achieved a higher median TAC level (ng/ml) vs. PO route (5.85 vs. 5 (P = 0.06)) despite receiving similar median cumulative tacrolimus dose before assessing TAC-level. Fifty percent of patients achieved TAC level ≥6 ng/ml in SL-group vs. 35.8% in PO-group (P = 0.14). The incidence of neurotoxicity, nephrotoxicity, and graft rejection during hospital stay were similar in both the groups (P = 0.56, 0.82, and 0.28, respectively).

Conclusion

SL-tacrolimus is safe and provides similar trough levels to PO-tacrolimus and may be considered as a viable alternative whenever inadequate TAC levels are anticipated through the per-oral route.

Kasai Portoenterostomy, Successful Liver Transplantation, and Immunosuppressive Therapy for Biliary Atresia in a Female Baby: A Case Report

Background

Biliary atresia (BA) is a severe neonatal progressive cholangiopathy of unknown etiology. A timely Kasai portoenterostomy (KPE) improves survival of the native liver in patients with BA, although liver transplantation remains the ultimate treatment for most (60%-80%) patients. However, postoperative adverse effects of liver transplantation may be significant. In addition, patients require lifelong immunosuppressive therapy after liver transplantation.

Case Summary

Here, we report a case of a newborn female baby (birthday: 10-03-2018) with congenital BA (confirmed at 76 days of life) who survived KPE (first surgery at 85 days of life) and underwent successful living-related liver transplantation (LRLT) (second surgery at 194 days of life). Additionally, we reviewed the existing literature on BA. After KPE (at 85 days of life), the liver function of the baby did not improve, and the indicators of liver and kidney function showed a trend of aggravation, indicating that the liver function had been seriously damaged before KPE (at 85 days of life), demonstrating the urgent need for liver transplantation surgery. The female baby survived after part of her father's liver was successfully transplanted into her body (at 194 days of life). The patient recovered successfully. No other diseases were found at the 4-year follow-up, and all indices of liver and kidney functions tended to be normal.

Conclusion

This case highlights the following. Postoperative alkaline phosphatase was consistently above the normal range, although the reason for this was unclear; neither tacrolimus nor cyclosporine A has formulations designed specifically for infants, which does not meet the needs of clinical individualized medication, suggesting that these anti-rejection drugs are future development directions. Only one case of congenital BA has been found thus far in Hefei, and this case has extremely important reference significance for the prevention, treatment, and diagnosis of BA in Hefei, Anhui province.

Immunosuppressive effect of PLGA-FK506-NPs in treatment of acute cardiac rejection via topical subcutaneous injection

FK506, a first-line immunosuppressant, is routinely administered orally and intravenously to inhibit activation and proliferation of T cells after heart transplantation (HT). Current administration route is not conducive enough to exert its efficacy in lymphatic system. Herein, we proposed that subcutaneous (SC) administration of FK506-loaded nanoparticles (PLGA-FK506-NPs) would be valuable for treating acute rejection after HT. The biodistribution and pharmacokinetic study revealed that it could effectively deliver FK506 to the lymph nodes (LNs) due to their suitable particle size, especially in inguinal LNs. Subsequently, the therapeutic efficacy of PLGA-FK506-NPs on the HT model was evaluated using intravenous (IV), intragastric (IG), or SC injection. Histopathological analysis revealed that 80% of allografts exhibited only grade 1R rejection with negligible lymphocyte infiltration in the SC group. The IV group exhibited 40% 1R rejection with mild lymphocyte infiltration and 20% grade 3R that require further intervention, and the IG group exhibited grades 40% 3R rejection with more lymphocyte infiltration. Moreover, the infiltration of T cells and the secretion of IL-2 and IFN-γ were significantly reduced in the SC group compared with the IG or IV group. The mean survival time (MST) further revealed that 50% of grafts treated with PLGA-FK506-NPs via SC injection survived longer than IG and IV groups. Moreover, the MST of single-dose SC injection of PLGA-FK506-NPs demonstrated that it would effectively reduce the required dose for a similar therapeutic effect. Overall, these results indicate that SC administration of PLGA-FK506-NPs is a more effective route for chronic FK506 treatment.

Use of sublingual tacrolimus in adults undergoing hematopoietic cell transplant: A pilot study

INTRODUCTION

Orally administered tacrolimus is widely used in hematopoietic cell transplant patients, but multiple clinical situations may arise rendering oral administration infeasible. The undesirable sequelae of intravenous administration, including toxicity, challenges with administration and cost call for innovative solutions to conserve existing supply and optimize safety and efficacy of medication delivery. We sought to demonstrate feasibility of sublingual tacrolimus use and estimate a sublingual-to-oral (SL:PO) conversion ratio in the hematopoietic cell transplant setting.

METHODS

Ten adults undergoing allogeneic hematopoietic cell transplant received tacrolimus 0.04 mg/kg/dose twice daily. Initial doses were given via sublingual route and a steady state trough level was collected after 4 consecutive doses. Participants were then switched to oral tacrolimus, the dose adjusted for a goal trough 8-12ng/mL, and another steady state trough was drawn. Total daily dose was divided by trough concentration for each route to determine the dosing ratio of SL:PO.

RESULTS

Median trough level following sublingual administration was 11.3 ng/mL. Three of these were within goal, 3 were low (4.7-6.4 ng/mL) and 4 were elevated (15.9-18.6 ng/mL). Median SL:PO ratio was 1.02. In 5 participants the SL:PO ratio was <1 (range 0.57-0.94) and in 5 the ratio was ≥1 (range 1.10-1.92). No significant barriers or intolerance to sublingual tacrolimus use were noted.

CONCLUSIONS

Results demonstrate reliable absorption with sublingual tacrolimus use in patients undergoing hematopoietic cell transplant. Sublingual administration may allow for avoidance of the undesirable complications of IV tacrolimus, such as increased toxicities, required hospitalization for continuous infusion, risk of dose conversion and dilution errors and increased cost.Trial Registry name: Use of Sublingual Tacrolimus in Adult Blood and Marrow Transplant Patients, NCT04041219https://clinicaltrials.gov/ct2/show/NCT04041219?term=NCT04041219&draw=2&rank=1.

Impact of CYP3A5 phenotype on tacrolimus concentrations after sublingual and oral administration in lung transplant

Aim: This study evaluated the impact of CYP3A5 genotype and other patient characteristics on sublingual (SL) tacrolimus exposure and compared the relationship with oral administration. Patients & methods: Tacrolimus concentrations were retrospectively collected for adult lung transplant recipients, who were genotyped for CYP3A5*3, CYP3A4*22, CYP3A7*1C, and POR*28. Regression analyses were performed to determine covariates that impacted the SL and oral tacrolimus concentration/dose ratios. Results: An interaction of CYP3A5 genotype and CYP3A inhibitor increased the SL concentration/dose, while cystic fibrosis decreased the SL concentration/dose. The oral concentration/dose was independently associated with these covariates and was increased by serum creatinine and number of tacrolimus doses. Conclusion: This study suggests personalized dosing strategies for tacrolimus likely need to consider characteristics beyond CYP3A5 genotype.

Immunosuppressive drugs and the gastrointestinal tract in renal transplant patients

Gastrointestinal (GI) discomfort is common after renal transplantation and can be caused by the use of various immunosuppressive drugs. GI symptoms affect the quality of life, lead to an impaired graft survival and an increased mortality. Moreover, diseases and disturbances of the GI tract also affect the pharmacokinetics of immunosuppressive drugs. This review addresses the interaction between immunosuppressive agents and GI disorders. The GI tract is involved in the metabolism of several immunosuppressive drugs. Calcineurin inhibitors, mTor inhibitors, and corticosteroids are subjected to metabolism by the intestinal cytochrome P450 (CYP3A) and by the drug efflux pump ABCB1. Mycophenolate is partly metabolized in the stomach and intestine and undergoes enterohepatic recirculation. Gastrointestinal disturbances can lead to a modified exposure to immunosuppressive drugs. In the first and second part of this review, we focus on the role of the GI tract in the pharmacokinetics of the immunosuppressive drugs and how to adjust immunosuppressive therapy in patients with vomiting, need for tube feeding, delayed gastric emptying, intestinal resection, and diarrhea. In the third part, we review the GI adverse effects of the various immunosuppressive drugs, with special attention for diarrhea and dyspepsia. Finally, we discuss the effects of drugs used for relief of GI complaints on the exposure to immunosuppressive agents.