Viracor TRAC® Lung dd-cfDNA

The Viracor TRAC^® (Transplant Rejection Allograft Check) donor-derived cell-free DNA (dd-cfDNA) assay is designed to utilize a noninvasive liquid biopsy to monitor the percentage of dd-cfDNA in transplant recipient plasma post-transplant using next generation sequencing (NGS).

About Lung Transplant

Lung transplants, compared to other solid organ transplants, are increasing year over year the most. The current 1 year survival rate for those with a first time lung transplant is at 87.9%, falling to 56.0% at 5 years post-transplant. Lung transplant represents one of the lowest long term survival rates among solid organ transplant recipients.

Based on OPTN data as of March 1, 2019
https://optn.transplant.hrsa.gov/data/view-data-reports/national-data/

About Transplant Rejection and dd-cfDNA

The current standard method of allograft rejection diagnosis and surveillance is by organ biopsy, which is an invasive technique that suffers from high cost and multiple potential serious complications for the patient. Biopsies may also be inconclusive and lead to adverse treatment decisions. Recently, quantification of dd-cfDNA (by NGS methods) in a transplant recipient’s plasma has been developed to non-invasively monitor and diagnose organ rejection in transplant recipients.

Research has shown that donor-derived cell-free DNA (dd-cfDNA) found in a patient’s plasma may be used as a liquid biopsy marker for identifying solid organ transplant rejection. Donor-derived cell-free DNA is released when the donated organ is attacked by either antibody or cell-mediated rejection processes. While the exact mechanism of action resulting in the circulating dd-cfDNA is not known, some researchers have speculated it could be produced by apoptosis, necrosis or active secretion. Regarded as a potential universal molecular biomarker, the concept of dd-cfDNA is being applied to several different solid organ transplant recipient populations. Not only is the method noninvasive, but the method has the ability quantify the percentage of cell-free DNA post organ transplant.

About Viracor TRAC^® dd-cfDNA

The Viracor TRAC^® dd-cfDNA test enables providers to detect solid organ transplant rejection using plasma isolated from Streck BCT tubes, providing essential information in a non-invasive way, which may be useful in the diagnosis of solid organ transplant rejection. This test utilizes a bioinformatics pipeline that analyzes NGS and genome-wide recipient genotype data to determine the percentage of dd-cfDNA present, which strongly correlates with allograft injury due to rejection. The licensed algorithm accurately quantifies the donor-derived fraction of cell-free DNA without need for donor genotype information, even when the donor is closely related (e.g., sibling kidney donors).  The design of this test also enables the determination of dd-cfDNA concentrations over a much wider dynamic range than currently possible with other methods.

The Viracor TRAC^® dd-cfDNA assay determines the percentage of circulating cell-free DNA (cfDNA) in transplant recipients derived from donor grafts. cfDNA is extracted from plasma isolated from whole blood collected in Streck BCT tubes within seven days of collection and unbiased sequencing is performed. NGS and genome-wide recipient genotype data are then analyzed by a bioinformatics pipeline that calculates the percentage of dd-cfDNA present. This test was developed and its performance characteristics determined by Eurofins Viracor. This test has not been cleared or approved for diagnostic use by the U.S. Food and Drug Administration.

This test is not suitable for use during pregnancy, if the donor and recipient are identical twins, if the patient has received multiple transplants from different donors, or if the donor and recipient are siblings from a consanguineous marriage. In these scenarios, the bioinformatics pipeline will generate an inaccurate result.