Comparability of Fingerprick vs Venous Blood for Tacrolimus Monitoring

Developing an LC-MS/MS Method for Measurement of Tacrolimus and Creatinine Concentration From Finger-prick Blood Collected Using the Mitra Device

Organ transplant rejection occurs when the immune system attacks the transplanted organ. To prevent rejection, transplant-patients are given immunosuppressant drugs which can suppress the immune system from attacking the transplanted organ. Patients who have had a kidney-transplant take immunosuppressant drugs such as tacrolimus, but the dosage must be closely monitored through regular blood tests to avoid complications like organ failure and kidney damage. The current practice at Nottingham University Hospitals NHS Trust is that kidney-transplant patients being monitored for tacrolimus have regular blood samples taken by venepuncture (vein), and the samples are sent to the laboratory to be measured using liquid chromatography-tandem mass spectrometry (LC-MS/MS), a technique used in chemistry to identify and quantify substances in a sample. Patients will also often have their blood-creatinine measured to get an idea of kidney health. Visits to the GP/hospital for this type of blood collection can be disruptive to a patient's daily life and stretches resources of the NHS. An alternative blood sample collection process involves the use of a hand-held blood collecting device called a Mitra device, designed to allow patients to collect samples at home through a finger-prick and send them by post for analysis. This method is especially beneficial for those who find hospital visits challenging or venepuncture painful.

This study aims to develop an LC-MS/MS method for measurement of tacrolimus and creatinine, using finger-prick samples collected on the Mitra device. To do this, kidney-transplant patients who are having routine venepuncture to measure tacrolimus and creatinine will simultaneously have a finger-prick sample collected using the Mitra device. Both the venepuncture sample and finger-prick samples will be analysed using existing LC-MS/MS technology to determine tacrolimus and creatinine values. The LC-MS/MS analysis method for the finger-prick samples collected using the Mitra device will be optimised and then results obtained using this method will be compared to the results obtained from venepuncture-collected samples to ensure consistency of results. Agreement of results between the two analysis methods will confirm the suitability of LC-MS/MS method for the measurement of tacrolimus and creatinine using samples collected using the Mitra device.

Study Overview

• Status: Completed
• Conditions: Immunosuppression
• Intervention / Treatment: Device: Mitra Microsampling Device

• Study Type: Observational
• Enrollment (Actual): 56

Contacts and Locations

Study Locations

• United Kingdom
  • Nottingham, United Kingdom, NG7 2UH
    • Nottingham University Hospitals NHS Trust

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Patients attending renal clinic who are receiving immunosuppressant treatment (tacrolimus) and require regular monitoring.

Description

Inclusion Criteria:

• Patients attending renal clinic who are receiving immunosuppressant treatment (tacrolimus) and require regular monitoring.

Exclusion Criteria:

• No exclusion criteria

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Validation of an in-house LC-MS/MS method and L4L-Analyst quantitative software for the measurement of tacrolimus and creatinine using capillary fingerprick samples collected with a Mitra device.	Validation of an in-house LC-MS/MS method for the measurement of tacrolimus and creatinine using capillary fingerprick samples collected with a Mitra device to UKAS standards, in accordance with ISO 15189, for routine clinical practice.	6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Questionnaire to assess whether the new sample collection method improves patient experience	Patient satisfaction questionnaire using a 5-point likert scale	6 months

Collaborators and Investigators

• Sponsor: Nottingham University Hospitals NHS Trust
• Investigators: Principal Investigator: Donna M Fullerton, PhD, FRCPath, Nottingham University Hospitals NHS Trust

Publications and helpful links

General Publications

• Marshall DJ, Kim JJ, Brand S, Bryne C, Keevil BG. Assessment of tacrolimus and creatinine concentration collected using Mitra microsampling devices. Ann Clin Biochem. 2020 Sep;57(5):389-396. doi: 10.1177/0004563220948886. Epub 2020 Aug 20.

Study record dates

Study Major Dates

• Study Start (Actual): January 7, 2025
• Primary Completion (Actual): March 14, 2025
• Study Completion (Actual): March 14, 2025

Study Registration Dates

• First Submitted: August 23, 2024
• First Submitted That Met QC Criteria: September 2, 2024
• First Posted (Actual): September 5, 2024

Study Record Updates

• Last Update Posted (Actual): June 24, 2025
• Last Update Submitted That Met QC Criteria: June 23, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Other Study ID Numbers: 24PA006

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No