Pharmacokinetics of Sublingual Versus Oral Tacrolimus in Patients Awaiting Kidney Transplantation

Phase 4

Completed

Conditions: Kidney Failure, Chronic

Interventions: Drug: Tacrolimus (Arm A)
Drug: Tacrolimus (Arm B)
Drug: Clotrimazole Troche
Drug: Nystatin Suspension

Registration Number: NCT00629122

Lead Sponsor: Weill Medical College of Cornell University

Brief Summary: Tacrolimus (Prograf) belongs to a class of medications known as the calcineurin inhibitors. It is a maintenance drug that is used to prevent rejection in kidney, liver, and heart transplant recipients. Calcineurin inhibitors display high pharmacokinetic (the body's effects on a drug) variability and necessitate use of blood tests to ensure that adequate drug levels are present to maintain effectiveness and safety. Early after transplant or at times when tacrolimus cannot be taken by mouth, alternative routes of administration are sought. Although an intravenous (through the vein) product is available, it can be toxic to the kidneys and has been associated with allergic reactions. Drug delivery via the oral mucosa is an alternative method of systemic drug administration which offers an alternative when oral administration is impractical (gastrointestinal dysmotility, reduced drug absorption, intestinal failure, difficulty in swallowing, or in those with nausea or vomiting). Administration of tacrolimus by the sublingual route may allow for direct entry into the systemic circulation and bypasses problems associated with drug absorption and breakdown that take place in the small intestine.

Detailed Description: Tacrolimus (Prograf) belongs to a class of medications known as the calcineurin inhibitors. It is a maintenance drug that is used to prevent rejection in kidney, liver, and heart transplant recipients. Calcineurin inhibitors display high pharmacokinetic (the body's effects on a drug) variability and necessitate use of blood tests to ensure that adequate drug levels are present to maintain effectiveness and safety. The amount of oral tacrolimus that is absorbed varies in all patient populations studied. Tacrolimus is metabolized or broken down for elimination by the liver and small intestine via cytochrome P450 (CYP)3A4, CYP 3A5, and p-glycoprotein enzyme systems. Enzyme activity is affected by several single nucleotide polymorphisms (SNPs) in an individuals genetic make-up and differences in expression may contribute to variations in tacrolimus pharmacokinetics. There are number of drug-drug interactions where concomitantly administered medications can increase or decrease this break down of tacrolimus. Early after transplant or at times when tacrolimus cannot be taken by mouth, alternative routes of administration are sought. Although an intravenous (through the vein) product is available, it can be toxic to the kidneys and has been associated with allergic reactions. Studies in lung transplant recipients have utilized sublingual (under the tongue) tacrolimus administration with successful outcomes. Drug delivery via the oral mucosa is an alternative method of systemic drug administration which offers an alternative when oral administration is impractical (gastrointestinal dysmotility, reduced drug absorption, intestinal failure, difficulty in swallowing, or in those with nausea or vomiting). Administration of tacrolimus by the sublingual route allows for direct entry into the systemic circulation and bypasses problems associated with drug absorption and breakdown that take place in the small intestine. In order to learn more about the possible role of sublingual tacrolimus among transplant recipients we will administer tacrolimus sublingually. In addition, we will evaluate differences in expression and bioactivity of SNP polymorphisms and their effects in tacrolimus pharmacokinetics. Patients awaiting kidney transplantation who are listed on the kidney transplant waiting list or those with upcoming living donor transplants at our center will be administered five doses of sublingual tacrolimus followed by five doses of oral tacrolimus. We will evaluate and then compare the pharmacokinetic characteristics of sublingual and oral tacrolimus administration among the study participants. The purpose of this study is to assess the pharmacokinetic and pharmacodynamic parameters of tacrolimus after sublingual and oral administration. A secondary objective is to assess the drug-drug interaction between concomitant therapy with clotrimazole.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 5

Inclusion Criteria

Adult patients awaiting kidney transplantation aged ≥ 18 years

Exclusion Criteria

Patients concurrently treated with medications that interact with tacrolimus (other than clotrimazole)

Study & Design

Study Type: INTERVENTIONAL

Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
A: Tacrolimus and Nystatin Suspension	Tacrolimus (Arm A)	Administer sublingual tacrolimus 2 mg every 12 hours (subject weight \< 90 kg) or 3 mg every 12 hours (subject weight \> 90kg) (study day 1 - 3). Tacrolimus capsules will be opened and the contents placed under the participants tongue. Oral tacrolimus at same dose every 12 hours (study day 6 - 8). Tacrolimus capsules will be administered by mouth. Nystatin suspension 5 mL every 12 hours (study days 1 - 3 and 6 - 8).
B: Tacrolimus and Clotrimazole Troche	Tacrolimus (Arm B)	Administer sublingual tacrolimus 1 mg every 12 hours (subject weight \< 90 kg) or 2 mg every 12 hours (subject weight \> 90 kg) (study day 1 - 3). Tacrolimus capsules will be opened and the contents placed under the participants tongue. Oral tacrolimus at same dose every 12 hours (study day 6 - 8). Tacrolimus capsules will be administered by mouth. Clotrimazole troche 10 mg every 12 hours (study day 1 - 3 and 6 - 8).
B: Tacrolimus and Clotrimazole Troche	Clotrimazole Troche	Administer sublingual tacrolimus 1 mg every 12 hours (subject weight \< 90 kg) or 2 mg every 12 hours (subject weight \> 90 kg) (study day 1 - 3). Tacrolimus capsules will be opened and the contents placed under the participants tongue. Oral tacrolimus at same dose every 12 hours (study day 6 - 8). Tacrolimus capsules will be administered by mouth. Clotrimazole troche 10 mg every 12 hours (study day 1 - 3 and 6 - 8).
A: Tacrolimus and Nystatin Suspension	Nystatin Suspension	Administer sublingual tacrolimus 2 mg every 12 hours (subject weight \< 90 kg) or 3 mg every 12 hours (subject weight \> 90kg) (study day 1 - 3). Tacrolimus capsules will be opened and the contents placed under the participants tongue. Oral tacrolimus at same dose every 12 hours (study day 6 - 8). Tacrolimus capsules will be administered by mouth. Nystatin suspension 5 mL every 12 hours (study days 1 - 3 and 6 - 8).

Primary Outcome Measures

Name	Time	Method
C0 (ng/mL)	Day 3 and Day 8, time 0 (before tacrolimus dose)	Trough concentration
Tmax	Day 3 and Day 8, time of maximum concentration	Time to Maximum concentration (hours)
Cmax	Day 3 and Day 8, at time of maximum concentration	Maximum concentration (ng/mL)
Estimated AUC 0-6	Day 3 and Day 8, calculated based on concentrations measured between hours 0 and 6	Area Under the Concentration-Time Curve from 0-6 hours (mg-hr/L)
Tacrolimus Powder Dissolution Time	Day 3, minutes to powder dissolution	Tacrolimus Powder Dissolution Time during Sublingual Administration (minutes)

Secondary Outcome Measures

Name	Time	Method
Drug Interactions and Genotypes	2 weeks	Impact of drug interaction between tacrolimus and clotrimazole troche vs. nystatin suspension. Evaluate genotype polymorphisms that influence CYP3A4, CYP3A5, and p-glycoprotein expression to determine impact on sublingual and oral tacrolimus delivery.