Abbott's Tacrolimus assay provides consistent medication monitoring for organ transplant patients

A new study published in the journal Clinical Chemistry reported Abbott's (NYSE: ABT) ARCHITECT® Tacrolimus assay provides accurate and consistent medication monitoring for patients taking tacrolimus, an immunosuppressive medication, after receiving solid organ transplantation.

Tacrolimus is a calcineurin inhibitor often used in patients to help prevent organ rejection. For continued organ survival, a transplant patient must be monitored accurately and precisely to ensure the medication level is sufficient to prevent organ rejection and to help the organ remain functional. Currently, test methods used to monitor tacrolimus concentration in the blood are not standardized which may lead to varying results for patients. Underestimating tacrolimus levels could result in prescribing unnecessarily high doses of medication that could be toxic to the transplanted organ over time and may cause side effects contributing to a poor quality of life for the patient. Overestimating tacrolimus levels could lead to insufficient dosing, poor immunosuppression and subsequent organ rejection.

"A transplant patient might receive an organ at one facility and be monitored somewhere else. If that location uses an assay with poorer accuracy and precision, it could result in incorrect dosage decisions, so it is critical that test results measuring tacrolimus medication levels be comparable from site-to-site," said Dr. David Holt, co-author of the paper and Emeritus Professor of Bioanalytics at the University of London and director of Analytical Services International Ltd. in the United Kingdom. "The absence of standardization between the various assay techniques could result in the clinician receiving misleading information. Current low-dose regimens for tacrolimus and other anti-rejection medications require drug-monitoring assays with both high precision and sensitivity," he added. 

"Minimizing drug toxicity over time is considered one way to help improve long-term graft survival and preserve quality of life for transplant patients," said Daniel M. Levine, Ph.D., lead author of the study and director of the Iris and B. Gerald Cantor Clinical Research Laboratory at The Rogosin Institute in New York City. "To reduce toxicity risk, current guidelines suggest prescribing immunosuppressive drugs at the lowest levels possible without risking rejection," he added.

The ARCHITECT Tacrolimus assay is used for the quantitative determination of tacrolimus in human whole blood, as an aid in managing liver and kidney transplant patients receiving tacrolimus therapy. It is the only automated transplant monitoring test that meets published international guidelines for low-level monitoring. It is accurate and precise at low levels and shows consistent results between laboratories. 

"Kidney-transplant patients have a high incidence of cardiovascular complications which may be exacerbated by the long-term effects of taking calcineurin inhibitors," said Gregory Maine, Ph.D., co-author and associate research fellow, Diagnostics, Abbott. "The ARCHITECT Tacrolimus assay addresses an unmet clinical need for consistent site-to-site patient results by providing uniform instrumentation, test kits, calibrators and controls across the world."

According to the National Organ Procurement and Transplant Network, between January through October 2011, nearly 24,000 organ transplants were performed in the United States.