Limited Sampling Strategy for Extended-Release Tacrolimus, Envarsus®

  • Research type

    Research Study

  • Full title

    Development and Validation of a Limited Sampling Strategy (LSS) for Estimation of Extended-Release Tacrolimus, Envarsus® AUC in Adult Kidney Transplant Recipients

  • IRAS ID

    234163

  • Contact name

    Iain MacPhee

  • Contact email

    imacphee@sgul.ac.uk

  • Sponsor organisation

    St. George's, University of London

  • Duration of Study in the UK

    0 years, 11 months, 29 days

  • Research summary

    Tacrolimus is a cornerstone of the immunosuppressive drug regimens used to prevent rejection of solid organ transplants. While it is very effective at preventing rejection, toxicity including infections, increased risk of cancer, diabetes mellitus and kidney damage is a significant problem. There is a relatively narrow window (therapeutic range) between the blood concentration that is sufficient to prevent rejection and the blood concentration that causes toxicity. The formulation of Envarsus® was designed using MeltDose drug delivery technology to allow sustained release of the drug as it passes along the intestine, rather than the rapid absorption that occurs with twice daily immediate release tacrolimus formulations. The Envarsus® formulation delivers a pharmacokinetic profile with a lower maximum blood concentration (Cmax) with equivalent overall exposure over 24 hours (area under the concentration time curve or AUC 0-24) with the potential to reduce toxicity for equivalent efficacy compared to immediate release tacrolimus formulations. However, robust data supporting this assumption are not yet available. Tacrolimus dose individualization in clinical practice is usually based on measurement of blood concentration at a single time point immediately before the next dose (trough concentration) to provide an estimate for AUC 0-24. In planning clinical trials to test the hypothesis that Envarsus® is less toxic than twice daily immediate release tacrolimus, there is a need for a sampling strategy that estimates AUC more precisely and provides an indication of maximum blood concentration without a requirement for full 24 hour sampling which would be impractical. Ideally a limited sampling strategy should be based on a maximum of 4 blood samples, and ideally fewer, that can be collected within a working day. This study is designed to develop a sampling tool for use in subsequent studies of drug efficacy and toxicity.

  • REC name

    London - Bloomsbury Research Ethics Committee

  • REC reference

    18/LO/0524

  • Date of REC Opinion

    30 May 2018

  • REC opinion

    Further Information Favourable Opinion