oward Biomarkers for Chronic Graft-versus-Host isease: National Institutes of Health Consensus evelopment Project on Criteria for Clinical Trials n Chronic Graft-versus-Host Disease: III. Biomarker orking Group Report

Biology-based markers that can be used to confirm the diagnosis of chronic graft-versus-host disease (GVHD) or monitor progression of the disease could help in the evaluation of new therapies. Biomarkers have been defined as any characteristic that is objectively measured and evaluated as an indicator of a normal biologic or pathogenic process, a pharmacologic response to a therapeutic intervention, or a surrogate end point intended to substitute for a clinical end point. The following applications of biomarkers could be useful in chronic GVHD clinical trials or management: (1) predicting response to therapy; (2) measuring disease activity and distinguishing irreversible damage from continued disease activity; (3) predicting the risk of developing chronic GVHD; (4) diagnosing chronic GVHD: (5) predicting the prognosis of chronic GVHD; (6) evaluating the balance between GVHD and graft-versus-leukemia effects (graft-versus-leukemia or GVT); and (7) serving as a surrogate end point for therapeutic response. Such biomarkers can be identified by either hypothesis-driven testing or by high-throughput discovery-based methods. To date, no validated biomarkers have been established for chronic GVHD, although several candidate biomarkers have been identified from limited hypothesis-driven studies. Both approaches have his project was supported by the National Institutes of Health (NIH) National Cancer Institute, Office of the Director, Cancer Therapy Evaluation rogram, Intramural Research Program and Center for Cancer Research; National Heart Lung and Blood Institute, Division of Blood Diseases and esources; Office of Rare Diseases, NIH, Office of the Director; National Institute of Allergy and Infectious Disease, Transplantation Immunology Branch; nd the Health Resources and Services Administration, Division of Transplantation and the Naval Medical Research Center, C. W. Bill Young/Department f Defense Marrow Donor Recruitment and Research Program. he opinions expressed here are those of the authors and do not represent the official position of the National Institutes of Health or the US Government.