CareDx Inc. announced the results of a study led by the National Institutes of Health (NIH), published in TheJournal of Heart and Lung Transplantation, “Donor-derived Cell-free DNA as a Composite Marker of Acute Lung Allograft Dysfunction in Clinical Care,” that validates the ability of AlloSure® Lung to detect signs of organ rejection and infection in asymptomatic lung transplant recipients in a real-world, home-based surveillance setting. The use of AlloSure Lung also identified episodes of acute rejection and infection that would have been missed using a biopsy strategy alone. ALARM (Lung Allograft Remote Monitoring) was a real-world, multicenter, prospective study conducted from March 24 to September 1, 2020, at the height of the pandemic.

Four lung transplant centers used AlloSure Lung donor-derived cell-free DNA (dd-cfDNA) instead of surveillance bronchoscopy for transplant rejection surveillance in a home-based setting using CareDx RemoTraC™, an at-home blood draw phlebotomy service. The study showed that non-invasive AlloSure Lung effectively identified acute cellular rejection (ACR), antibody-mediated rejection (AMR), and infection in asymptomatic lung transplant patients during routine surveillance screening. For diagnosis of ACR, AMR, or infection in these patients, dd-cfDNA yielded a sensitivity of 73.9%, specificity of 87.7%, positive predictive value of 43.4%, and negative predictive value of 96.5%, with an area under the curve (AUC) of 0.82 using the ALARM investigator's protocol.

Using an AlloSure Lung surveillance strategy, there were 83% fewer invasive biopsies than would have been performed under a surveillance biopsy program.