XDx Sponsors Heart Transplant Recipient and Professional Golfer Erik Compton at The Ultimate Game at Wynn

XDx today announced its sponsorship of professional golfer and heart transplant recipient Erik Compton in The Ultimate Game at Wynn Las Vegas. The tournament is offering a winner-take-all prize of $2,000,000, the largest winner's purse in the history of golf. Compton is one of 12 finalists vying for this prize in this 2 day tournament. Compton, who received his transplant at age 12, holds the distinction of being the only professional golfer in the world to compete with a transplanted heart.

"For the past 15 years I have had to have invasive biopsies to check the health of my transplanted heart on a regular basis. Biopsies are painful, stressful and just generally unpleasant. If a simple blood test such as the AlloMap test was available to transplant patients back then, my experiences might have been dramatically different," said Compton. "An alternative like XDx's AlloMap test is so important because it allows heart transplant recipients to stay healthy without the trauma of biopsy. I am excited to be sponsored by and working with XDx." Erik takes 10 to 12 pills each day to suppress his immune system so that it will not reject the transplanted heart. Today, Compton plays golf professionally and will be among 12 players teeing up to win the richest jackpot in golf at The Ultimate Game.

Compton was diagnosed at age 9 with congestive cardiomyopathy, a condition in which the heart is enlarged and its ability to pump blood is impaired. At age 12, he received a donor heart. When his physicians urged him to not play contact or extreme sports, he began playing golf. He started competing at age 13 and became the top junior player in the country. His success on the junior amateur circuit attracted numerous university scholarship offers and he went on to become the first heart transplant recipient to earn and accept a scholarship to an NCAA Division 1 school. While at the University of Georgia, Compton was an All-Conference and an All-American athlete.

Commercially available since January 2005, AlloMap(R) molecular expression testing, based on a simple blood sample, helps physicians identify a patient's risk of rejection. With this information physicians may choose to reduce biopsies, the traditional method of rejection surveillance. Approximately 30 percent of all heart transplant patients reject their new heart at least once in the first year after transplantation. When testing reveals organ rejection, a patient's immunosuppressive regimen is typically adjusted. The test is currently offered at more than 50 transplant centers in the United States.

"Erik's stellar physical performance and his ability to thrive despite the obstacles and health challenges he has faced are an inspiration not only to heart transplant recipients but to everyone," said Pierre Cassigneul, president and chief executive officer of XDx. "We are pleased to sponsor Erik and wish him luck at Wynn. AlloMap testing is an ideal test for someone as healthy and successful as Erik. In stable patients, physicians are minimizing the number of painful, risky and anxiety-causing biopsy procedures as well as using the test with other clinical indicators to manage immunosuppression to reduce the potential of serious consequences including cancer, infection and kidney failure." For every single birdie Compton makes, XDx will donate $777 to the South Florida Transplant Foundation.

About XDx

XDx's mission is to improve patient care by developing molecular diagnostics that translate an individual's immune status into clinically actionable information. Founded in 2000, XDx is a molecular diagnostics company that utilizes state-of-the-art genomic technology and sophisticated bioinformatics analysis to understand and measure the immune processes that underlie specific immune-mediated conditions. Physicians can use this information to optimize patient treatment and minimize the long-term consequences of immunosuppressive therapies.

XDx's science and technology is now being evaluated in patients with solid organ transplants. Building on the discoveries made during the development of AlloMap testing for heart transplant patients, included the identification of many genes and pathways involved in tissue rejection, XDx is now developing a product for use by physicians to better manage lung transplant patients. Beyond the use of AlloMap testing in assessing immune response in solid organ transplantation, XDx scientists are applying similar approaches to create new molecular diagnostic tests for the improved clinical management of immune- mediated inflammatory diseases, such as systemic lupus erythematosus (SLE or lupus), to diagnose and predict clinical flares common in a variety of these diseases.

In addition to its potential for use by physicians for better patient management, the XDx approach is of interest to pharmaceutical companies looking to use biomarkers predictive of drug efficacy in order to proactively identify patient response and to better target their drug development efforts and clinical trials. More information can be found at http://www.xdx.com.

AlloMap Molecular Expression Testing

The first product using XDx's unique approach is AlloMap molecular expression testing. This service, offered through the XDx CLIA-certified clinical laboratory since January 2005, is being used by a number of leading cardiac transplant centers in the United States to monitor patients following their heart transplants. The scientific and clinical validation of this technology has been described in a peer-reviewed article published in the American Journal of Transplantation. More information can be found at http://www.allomap.com.