Preemptive genetic testing to guide tacrolimus treatment for kidney transplant patients

A Multicentre, Controlled, Randomised and Single-blind, Adaptive Phase IV Protocol to Evaluate Effectiveness and Cost-effectiveness of Pre-emptive Genotyping Strategy to Optimise Tacrolimus Dosage in a Pretransplant Chronic Kidney Disease Population Cohort

Phase 4 Interventional Instituto de Investigación Hospital Universitario La Paz · NCT06701825

This study will test whether doing a genetic test before transplant to guide tacrolimus dosing helps people on the kidney transplant waiting list stay safer and use health resources more efficiently.

Quick facts

PhasePhase 4
Study typeInterventional
Enrollment114 (estimated)
SexAll
SponsorInstituto de Investigación Hospital Universitario La Paz Academic / other
Locations1 site (Madrid, Madrid)
Trial IDNCT06701825 on ClinicalTrials.gov

What this trial studies

This is a nationwide, multi-centre, adaptive, single-blinded randomized Phase IV trial nested in the iPHARMGx master protocol that compares preemptive pharmacogenetic testing to current standard of care for patients likely to receive tacrolimus. Eligible transplant candidates will be genotyped for CYP3A5 before receiving tacrolimus; those with actionable variants will be randomized to guideline-based genotype-guided dosing or routine clinician-directed dosing. Participants will be followed prospectively at prespecified timepoints to capture drug levels, adverse drug reactions, clinical endpoints, and health-care resource use. A cost-effectiveness analysis will be performed alongside clinical outcomes, and an independent Data Monitoring Committee will review safety and trial conduct.

Who should consider this trial

Good fit: Adults on the kidney transplant waiting list who can give informed consent, are willing to be followed, and have not previously had CYP3A5 genotyping are the intended participants.

Not a fit: Patients with prior organ transplants, known allergy to tacrolimus, major comorbidities that alter drug handling, or those already genotyped for CYP3A5 are unlikely to benefit from enrollment.

Why it matters

Potential benefit: If successful, preemptive genotyping could lead to more accurate tacrolimus dosing, fewer drug-related toxicities, better graft care, and lower overall costs for patients and the health system.

How similar studies have performed: Smaller trials and observational studies have shown that CYP3A5-guided dosing improves early tacrolimus concentration control, but large multicentre, real-world demonstrations of clinical and cost-effectiveness remain limited.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Participants must be willing and able to provide written informed consent prior the initiation of any study procedures.
2. Subject or their legally authorized representative has voluntarily signed the informed consent document.
3. Participant is on the waiting list for a kidney transplant.
4. Subject is able and willing to take part and be followed-up for the majority of the study duration, and adhere to the procedures specified in this protocol.
5. Subjects must be naïve to any genotyping test of the following genes: CYP3A5.

Exclusion Criteria:

1. Known hypersensitivity/allergy reaction to tacrolimus or any of the excipients.
2. History of renal, heart, and/or liver transplant.
3. History or clinical evidence of any disease and/or existence of any surgical or medical condition, which might interfere in a relevant manner with the absorption, distribution, metabolism, or excretion of the study treatment, except for renal disease.
4. Any condition or situation precluding or interfering the compliance with the protocol.
5. Any condition at medical discretion for which renal transplantation and/or study treatment should not be received.

Where this trial is running

Madrid, Madrid

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Kidney Disease, ChronicTransplant RecipientImmunosuppressionTacrolimusKidney transplantCost-effectivenessPharmacogeneticPhase IV Clinical Trial
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.