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Study Comparing Tacrolimus Formulations for Preventing Kidney Transplant Rejection in Adults

Verified siteRegistered drugNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying the effectiveness and practicality of two medications, Envarsus and Advagraf, in patients who have received a kidney transplant. Both medications contain the active ingredient tacrolimus, which is used to prevent the body from rejecting a transplanted kidney. The study aims to compare how well these two medications are absorbed by the body and to determine if one is superior to the other in terms of how much of the drug is available in the bloodstream after taking it.

Participants in the study will be adults who have undergone a kidney transplant. The study will involve taking one of the two medications once daily. The trial will last for a period of up to three years, during which various health parameters will be monitored. These include the levels of tacrolimus in the blood, kidney function, and any side effects experienced. The study will also look at how quickly patients reach the desired drug levels in their blood and how stable these levels remain over time.

The purpose of this study is to gather information that could help improve the management of kidney transplant patients by identifying the most effective and convenient medication regimen. By comparing Envarsus and Advagraf, researchers hope to provide valuable insights into which formulation offers better outcomes for patients in terms of drug absorption and overall health after a kidney transplant.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Joining the study

    Upon joining the study, the patient will be randomly assigned to one of two groups. Each group will receive a different formulation of the medication tacrolimus, which is used to prevent organ rejection after a kidney transplant.

  2. Step 2

    Medication administration

    The patient will take the assigned medication once daily. The two formulations being compared are Envarsus and Advagraf. Both are prolonged-release forms of tacrolimus, meaning they release the medication slowly over time.

    The specific dosage will depend on the formulation assigned. For Advagraf, available dosages include 5 mg, 0.5 mg, 3 mg, and 1 mg capsules. For Envarsus, available dosages include 0.75 mg, 1 mg, and 4 mg tablets.

  3. Step 3

    Monitoring and assessments

    The patient's blood levels of tacrolimus will be monitored at various intervals: day 4, day 14, day 28, and week 12 after transplantation. This monitoring helps assess how well the medication is working and its concentration in the body.

    The primary goal is to measure the C/D ratio (concentration/dose ratio) at 12 weeks to evaluate the bioavailability of the medication.

  4. Step 4

    Follow-up evaluations

    Additional evaluations will occur at 1, 2, and 3 years post-transplantation. These evaluations will include assessments of kidney function, incidence of rejection episodes, and any adverse reactions to the medication.

    The study will also track the patient's quality of life using a specific questionnaire designed for kidney transplant recipients.

  5. Step 5

    Study completion

    The study is expected to conclude by March 31, 2029. Throughout the study, the patient will continue to receive regular medical care and monitoring to ensure their safety and the effectiveness of the treatment.

Who can join the trial?

5 criteria

  • Must provide a signed and dated written informed consent, which means you agree to participate in the study after being informed about it.
  • Must be an adult, which means you are 18 years old or older, whether male or female.
  • Must have kidney problems that require a kidney transplant and be approved to receive either a first or second kidney from a living or deceased donor.
  • Must have a blood type that is compatible with the donor kidney. This means your blood type matches with the donor's blood type.
  • Must be able to swallow a medication called tacrolimus, which is available in tablet or capsule form.

Who cannot join the trial?

6 criteria

  • Patients who are not adults cannot participate. This means only individuals who are 18 years or older are eligible.
  • Patients who have not received a kidney transplant are not eligible. The study is for those who have had a kidney transplant.
  • Patients who are not taking tacrolimus, a medication used to prevent organ rejection, cannot participate.
  • Patients who are part of a vulnerable population, such as those unable to give consent, are not eligible.
  • Patients who are pregnant or breastfeeding cannot participate in the study.
  • Patients with any medical condition that the study doctors believe would make participation unsafe are not eligible.
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Investigated drugs

  • Envarsus

    is a medication used in this trial to help prevent the body from rejecting a transplanted kidney. It is a once-daily oral formulation of tacrolimus, which is an immunosuppressant. The trial aims to assess how well this formulation is absorbed by the body compared to another tacrolimus formulation.

  • Advagraf

    is another once-daily oral formulation of tacrolimus used in the trial. Like Envarsus, it is used to prevent kidney transplant rejection by suppressing the immune system. The trial compares the absorption and effectiveness of Advagraf to that of Envarsus in kidney transplant patients.

What is already known about the treatment

  • Envarsus

    Envarsus is an oral medication used to prevent organ rejection in adult patients who have received a kidney transplant. It is currently being studied in clinical trials to compare its effectiveness and bioavailability with another tacrolimus formulation, Advagraf. Envarsus works by suppressing the immune system to prevent it from attacking the transplanted organ. It belongs to the pharmacological class of immunosuppressants, specifically calcineurin inhibitors, which help maintain the balance of immune response in the body.

  • Advagraf

    Advagraf is an oral medication designed to prevent rejection in patients who have undergone a kidney transplant. It is part of ongoing clinical trials to evaluate its bioavailability compared to Envarsus, another tacrolimus formulation. Advagraf functions by inhibiting the immune system, reducing the risk of the body rejecting the new organ. It is classified as an immunosuppressant, specifically a calcineurin inhibitor, which helps control the immune system's activity.

Investigated diseases

Transplant Rejection – Transplant rejection occurs when the recipient's immune system attacks the transplanted organ or tissue, recognizing it as foreign. This immune response can lead to inflammation and damage to the transplanted organ. Rejection can be acute, happening shortly after the transplant, or chronic, developing over a longer period. Symptoms may include fever, pain at the transplant site, and reduced function of the transplanted organ. The severity and progression of rejection can vary, potentially leading to the failure of the transplanted organ if not managed.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-503531-18-00Protocol codeTaC:DropEstimated enrolment300 patientsSponsorUniversitaetsklinikum Regensburg AöR

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