Biomarkers in systemic lupus erythematosus.

Despite the longstanding interest and large number of publications on biomarkers in lupus, there are no validated and widely accepted biomarkers of systemic lupus erythematosus to date. To achieve the ultimate goal, to have a biomarker as a surrogate endpoint in clinical studies, candidate biomarkers have to first be validated in a statistically rigorous way. However, to qualify as a surrogate endpoint, even validated biomarkers have to go through a process that demonstrates that they accurately reflect a clinically important outcome. These goals can only be achieved in large multicenter, properly conducted studies. We reviewed the difficulties involved in developing validated biomarkers for systemic lupus erythematosus and summarized the available data on the most promising biomarker candidates of disease susceptibility and disease activity. We also report on the current status of a multicenter initiative to concentrate efforts of biomarker development.