Randomized controlled trials in systemic lupus erythematosus: what has been done and what do we need to do?

The study of systemic lupus erythematosus (SLE) is a challenging undertaking. It is difficult to assess outcomes in SLE randomized controlled trials (RCTs), and this is illustrated by the lack of new therapies approved for use in lupus. In a disease that is waxing and waning, and requires constantly changing medications, identifying treatment effects of new therapies may be difficult, and the use of potentially toxic therapies requires a rigorous understanding of the benefit to risk ratio. Some issues that need to be considered by the investigator in designing these studies include: 1) should the trial focus on patients with active or inactive disease; 2) which of the measures of disease activity should be used or should prevention of flares be examined; 3) should the study focus on defined organ specific endpoints or utilize one of the available disease activity indices to identify changes in disease activity; 4) should the trial be a superiority trial or an equivalence trial. This review summarizes the critical issues involving the design of studies in lupus and provides the reader with suggestions and recommendations for consideration before embarking on trials in this area.