Use of sublingual tacrolimus in lung transplant recipients

Safety and Efficacy of Perioperative Sublingual Tacrolimus in Pancreas Transplant Compared With Oral Tacrolimus

OBJECTIVES

Early posttransplant, the administration of oral or enteral medications in pancreas transplant is challenging because of the management of postoperative ileus and gastroparesis. The use of sublingual tacrolimus may offer a promising alternative. The objective of this study was to compare the pharmacokinetics and perioperative outcomes between oral and sublingual tacrolimus in pancreas transplant.

MATERIALS AND METHODS

This was a single-center, retrospective study of pancreas transplants between January 1, 2011, and July 1, 2018. We transitioned our tacrolimus protocol from oral to sublingual dosing in pancreas transplant patients beginning January 1, 2017.

RESULTS

This analysis included 54 pancreas transplant recipients, with 17 patients on sublingual tacrolimus matched to 37 patients on oral tacrolimus. Within the sublingual group, it took a mean of 3.2 days to achieve a therapeutic tacrolimus trough level (≥8 ng/mL) compared with a mean of 3.8 days in the oral group (P = .175). There was no difference in the incidence of hyperkalemia and supratherapeutic tacrolimus levels between groups. The conversion factor from sublingual to oral in this patient population was 0.67, which was different than what has been reported in other populations. Clinical outcomes were similar between groups.

CONCLUSIONS

Sublingual tacrolimus use in pancreas transplant patients appears to be a safe and effective strategy to avoid oral or intravenous therapy in the perioperative period and may reduce the time to achieve therapeutic levels.

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.

Determining the conversion ratios for oral versus sublingual administration of tacrolimus in solid organ transplant recipients

Tacrolimus is utilized as maintenance immunosuppression in solid organ transplant (SOT). Current literature has reported conflicting conversion ratios when transitioning between oral and sublingual tacrolimus, and the exact conversion ratio has not been fully established in SOT. The purpose of this study was to determine the conversion ratios between oral and sublingual tacrolimus needed to achieve equivalent whole blood concentrations in heart, kidney, liver, and lung transplant recipients. A retrospective, single-center analysis was conducted at Mayo Clinic in Florida. One hundred and eighteen hospitalized SOT recipients who received oral and sublingual tacrolimus during the same inpatient admission from June 1, 2012, through June 1, 2017, were reviewed. The median conversion ratio of sublingual to oral tacrolimus was 1.34 (IQR: 1.03-1.93) in all SOT, 1.25 (IQR: 1.08-1.64) in heart transplant, 1.23 (IQR: 1.1-2.06) in kidney transplant, 1.64 (IQR: 1.27-2.29) in liver transplant, and 1.34 (IQR: 0.94-1.93) in lung transplant. A slightly higher dose of oral tacrolimus is needed in the majority of solid organ recipients in our population when converting between sublingual to oral tacrolimus administration.

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.

Individualizing immunosuppression in lung transplantation

Immunosuppression management after lung transplantation continues to evolve, with an increasing number of agents available for use in various combinations allowing for more choice and individualization of immunosuppressive therapy. Therapeutic developments have led to improved outcomes including lower acute rejection rates and improved survival. However, a one size fits all approach for any immunosuppressive strategy may not be best suited to the individual patient and ultimately patient specific factors must be considered when designing the immunosuppressive regimen. Recipient factors including age, race, co-morbidities, immunologic risk, genetic polymorphisms, concomitant and previous pharmacotherapy, and overall immunosuppression burden should be considered. There are several significant drug-drug interactions with select immunosuppressive agents utilized in lung transplant pharmacotherapy that must be considered when choosing and devising a dosing strategy for an individual immunosuppressive agent. Herein, considerations for immunosuppression management in the individual patient will be reviewed.

Sublingual administration improves systemic exposure of tacrolimus in kidney transplant recipients: comparison with oral administration

BACKGROUND

Tacrolimus (TCR) is an immunosuppressive drug used by oral administration. Intravenous (IV) TCR administration is required under conditions of gastrointestinal diseases or abdominal surgery at the onset of paralytic ileus. The infusion formulation needs a large dilution and therefore a careful technical management during continuous infusion by 24 h and may determine anaphylaxis, cardiac arrhythmia, QT prolongation and torsades de pointes. Sublingual (SL) TCR administration was suggested as an alternative route.

DESIGN

The aim of this study was to compare in the same kidney transplanted patients the TCR pharmacokinetic profiles by both the routes coupled with the pharmacoeconomic analysis. The study enrolled eight subjects undergoing renal transplantation and treated with TCR and methylprednisolone. TCR was administered by oral route at the scheduled dosage while the 50% of oral dosage was used by SL route, taking into account the absence of liver first pass.

RESULTS

Except for AUC, which resulted significantly increased after oral administration, all exposure parameters were not significantly different between the two routes of administration. Analysis of dose-adjusted exposure parameters showed significant increases in AUC and Cmin after SL administration confirming a better bioavailability of the SL route compared with oral route. Cost saving was obtained using the SL rather than the IV route of TCR delivery.

CONCLUSION

When oral administration of TCR is not advised, SL delivery represents an attractive option to IV administration.

Sublingual tacrolimus as an alternative to oral administration for solid organ transplant recipients

PURPOSE

Available data regarding sublingual tacrolimus were analyzed to provide recommendations for solid organ transplant recipients.

SUMMARY

Tacrolimus is an immunosuppressive agent with a narrow therapeutic range that is commonly used in solid organ transplantation. Achieving and maintaining appropriate tacrolimus exposure are critical for preventing rejection and minimizing toxicity. A variety of clinical situations requiring nonoral medication delivery arise, presenting the need for reliable alternative routes of tacrolimus administration. A review of the currently available literature revealed nine reports of sublingual tacrolimus use in human subjects. Seven reported that sublingual administration could achieve comparable tacrolimus trough concentrations to oral administration, but none investigated the correlation between tacrolimus trough concentration and exposure. One study of lung transplant recipients found that approximately 50% of the oral dose was needed to obtain therapeutic trough concentrations when converted to sublingual administration. Another study of patients with end-stage renal disease identified a similar sublingual:oral dosing ratio of 1:2. When converted from oral tacrolimus in combination with clotrimazole to sublingual administration, the sublingual:oral dosing ratio was 1:1.

CONCLUSION

In addition to enteral tube and i.v. tacrolimus dosing, sublingual administration may be considered for short-term use in patients who are unable to receive medications orally. Based on the available data, it is reasonable to initiate sublingual tacrolimus at 50% of the current or anticipated oral dose in the absence of interacting medications. Dosing must be individualized, taking into consideration concomitant interacting medications, and adjusted to target levels based on therapeutic drug monitoring.

Immunosuppression in lung transplantation

Lung transplantation can be a life-saving procedure for those with end-stage lung diseases. Unfortunately, long term graft and patient survival are limited by both acute and chronic allograft rejection, with a median survival of just over 6 years. Immunosuppressive regimens are employed to reduce the rate of rejection, and while protocols vary from center to center, conventional maintenance therapy consists of triple drug therapy with a calcineurin inhibitor (cyclosporine or tacrolimus), antiproliferative agents [azathioprine (AZA), mycophenolate, sirolimus (srl), everolimus (evl)], and corticosteroids (CS). Roughly 50% of lung transplant centers also utilize induction therapy, with polyclonal antibody preparations [equine or rabbit anti-thymocyte globulin (ATG)], interleukin 2 receptor antagonists (IL2RAs) (daclizumab or basiliximab), or alemtuzumab. This review summarizes these agents and the data surrounding their use in lung transplantation, as well as additional common and novel therapies in lung transplantation. Despite the progression of the management of lung transplant recipients, they continue to be at high risk of treatment-related complications, and poor graft and patient survival. Randomized clinical trials are needed to allow for the development of better agents, regimens and techniques to address above mentioned issues and reduce morbidity and mortality among lung transplant recipients.

Immunosuppression and allograft rejection following lung transplantation: evidence to date

The enduring success of lung transplantation is built on the use of immunosuppressive drugs to stop the immune system from rejecting the newly transplanted lung allograft. Most patients receive a triple-drug maintenance immunosuppressive regimen consisting of a calcineurin inhibitor, an antiproliferative and corticosteroids. Induction therapy with either an antilymphocyte monoclonal or an interleukin-2 receptor antagonist are prescribed by many centres aiming to achieve rapid inhibition of recently activated and potentially alloreactive T lymphocytes. Despite this generic approach acute rejection episodes remain common, mandating further fine-tuning and augmentation of the immunosuppressive regimen. While there has been a trend away from cyclosporine and azathioprine towards a preference for tacrolimus and mycophenolate mofetil, this has not translated into significant protection from the development of chronic lung allograft dysfunction, the main barrier to the long-term success of lung transplantation. This article reviews the problem of lung allograft rejection and the evidence for immunosuppressive regimens used both in the short- and long-term in patients undergoing lung transplantation.

Adverse effects of immunosuppressant drugs upon airway epithelial cell and mucociliary clearance: implications for lung transplant recipients

Optimal post-transplantation immunosuppression is critical to the survival of the graft and the patient after lung transplantation. Immunosuppressant agents target various aspects of the immune system to maximize graft tolerance while minimizing medication toxicities and side effects. The vast majority of patients receive maintenance immunosuppressive therapy consisting of a triple-drug regimen including a calcineurin inhibitor, a cell cycle inhibitor and a corticosteroid. Although these immunosuppressant drugs are frequently used after transplantation and to control inflammatory processes, limited data are available with regard to their effects on cells other than those from the immunological system. Notably, the airway epithelial cell is of interest because it may contribute to development of bronchiolitis obliterans through production of pro-inflammatory cytokines. This review focuses the current armamentarium of immunosuppressant drugs used after lung transplantation and their main side effects upon airway epithelial cells and mucociliary clearance.