PRAGUE--(BUSINESS WIRE)--XDx, Inc., a molecular diagnostics company focused on the development and commercialization of clinically differentiated, high value non-invasive tests to monitor immune status in transplant recipients and autoimmune diseases, today announced positive clinical results from the Company’s European-based Cardiac Allograft Rejection Gene Expression Observational (CARGO) II Study of AlloMap® Molecular Expression Testing. AlloMap is XDx’s FDA-cleared and CE-marked, easy and convenient, non-invasive blood test that aids physicians in determining a stable heart transplant patient’s risk of acute cellular rejection without requiring the use of endomyocardial biopsy. Results from the study confirmed the AlloMap test performance characteristics previously established in the first U.S.-based CARGO study.
In CARGO II, the mean test scores for samples associated with acute cellular rejection histology grades of ≥ 3A were significantly higher than test scores from samples from patients with no rejection seen on histology. Further, AlloMap demonstrated a negative predictive value of 98.4% at the most often used acute cellular rejection threshold. This validation is an exceptional additional level of evidence for a diagnostic test, comparable to the high standards seen in drug development which has required at least two Phase 3 trials. The findings were presented in a late breaking oral presentation at the International Society for Heart and Lung Transplantation (ISHLT)’s 32nd Annual Meeting & Scientific Sessions, being held April 18-21, 2012, in Prague, Czech Republic.
Jorg Stypmann, MD, transplant cardiologist in the Department of Cardiology and Angiology of the University Hospital Münster, Germany, who presented the CARGO II results, commented, “The surveillance of heart transplant recipients typically has required heart tissue obtained by biopsies to detect asymptomatic acute rejection, which can lead to graft dysfunction or loss. We believe that a sufficiently accurate blood test, such as AlloMap, especially in the context of the low prevalence of asymptomatic rejection, can provide a safer alternative to biopsy in stable, low-risk patients.”
Maria G. Crespo-Leiro, MD, Medical Director of the Advanced Heart Failure Transplant Unit at the Hospital Universitario A Coruña, Spain, and the first author of the study, stated, “It is critical to have data from patients in Europe in order for us to have confidence that AlloMap’s performance is reliable for use with our patients. The care of patients in Europe differs in the use of immunosuppressive medications and other factors that could impact risk of rejections and the performance of the gene expression test. Just as in centers in the U.S., we would like to reduce the need for heart biopsies in Europe by having the option to use a sufficiently accurate blood test instead.”
Johan Vanhaecke, MD, Professor at the University Hospital of Leuven, Belgium, and the senior author on the study, added, “Our ongoing objective is to further study the CARGO II patient cohort to determine whether serial AlloMap scores may predict the risk for future major allograft dysfunction or rejection events. This may lead to a method to individualize patient immunosuppressive regimens and improve long-term outcomes as a result.”
“We are pleased that presentation of the newly released results of this study contributed to an exciting and informative session today covering novel approaches to immune surveillance in heart transplantation,” said Stuart Sweet, ISHLT’s 2012 Scientific Program Chair.
About CARGO II
The CARGO II Study was designed to provide independent evidence of the clinical performance of XDx’s AlloMap® Molecular Expression Testing, assessing the correlation between the presence or absence of acute cellular rejection as determined by examination of endomyocardial biopsy specimens with results from AlloMap. Between 2006 and 2011, 741 heart transplant recipients from 17 participating transplant centers (13 in Europe and 4 in North America) were observed. The study evaluated over 8000 study visits that included surveillance biopsies (more than 3300), AlloMap test samples and other clinical observations.
AlloMap Molecular Expression Testing is a non-invasive gene expression test used to aid in the identification of heart transplant recipients with stable allograft function who have a low probability of moderate/severe acute cellular rejection at the time of testing in conjunction with standard clinical assessment. AlloMap testing measures the expression levels of 20 genes from a blood sample. The combined expression of these genes is represented as an AlloMap test score. AlloMap is performed in the XDx CLIA-certified laboratory and has been commercially available in the United States since 2005. AlloMap was cleared by the U.S. Food and Drug Administration in 2008 and was CE marked for the European Union in 2011. Use of AlloMap is also included in the International Society for Heart and Lung Transplantation (ISHLT) Practice Guidelines, published in August 2010, the worldwide standard for the care of heart transplant patients.
The International Society for Heart and Lung Transplantation (ISHLT) is a not-for-profit professional organization with more than 2,700 members from over 45 countries dedicated to improving the care of patients with advanced heart or lung disease through transplantation, mechanical support and innovative therapies via research, education and advocacy. For more information, visit www.ishlt.org.
XDx, Inc., based in Brisbane, California, is a molecular diagnostics company focused on the discovery, development and commercialization of clinically differentiated, high value, non-invasive tests to monitor immune status in transplant recipients and autoimmune disease and potentially improve long-term patient outcomes. The company has commercialized AlloMap Molecular Expression Testing, which aids physicians in determining the risk of acute cellular rejection in stable post-cardiac transplant patients. Some of the AlloMap technology developed by XDx may be applicable to other conditions that involve transplant rejection and diseases that affect the immune system. XDx also has an active diagnostic development program in system lupus erythematosus which includes several potential tests to address the high unmet medical need in managing this chronic disease. For more information, please visit: www.xdx.com.