DBS method not be validated against the standard of care venepuncture method due to quality of blood sample and variable tacrolimus extraction

The principal aim of this study is to define the relationship between tacrolimus concentrations determined from the finger prick DBS (Dry Blood Spot) method and those determined from blood samples collected by venepuncture in transplant recipients.

This will be a bioanalytical assay method cross-validation study using blood samples donated by up to 100 liver and 100 kidney transplant patients. Subjects who will be attending a routine outpatient follow-up visit will be asked to provide 3 whole blood venepuncture samples (each sample = 3 mL blood) and 3 finger prick DBS blood samples at predose and at 1 and 3 hours postdose. All subjects will be discharged from the study and clinical site at 3 hours postdose. Subjects will derive no benefit from the blood collection procedures and will be paid a predetermined stipend for participating in the study.

Inclusion Criteria:

• Stable adult transplant recipients aged ≥ 18 years maintained on a once daily Advagraf® based immunosuppressive regimen for the prophylaxis of kidney or liver allograft rejection.

Exclusion Criteria:

• Subjects who are still participating in another clinical study (e.g. attending follow up visits) or who have participated in a clinical study involving administration of an investigational drug (new chemical entity) in the past 3 months.

Stable kidney or liver transplant recipient receiving Advagraf® (tacrolimus) therapy