Early stopping of clinical trials in lupus and other uncommon rheumatologic diseases

Use of statistical methods for early stopping of clinical trials allows mor e efficient and ethical utilization of subjects. In uncommon diseases, wher e the pool of potential subjects is limited, these methods provide a way to maximize the information gathered from trials. For trials in lupus, method s for early stopping should be more widely utilized. We discuss the ethics, practical aspects, pros and cons, and statistical foundations of some esta blished methods for early stopping, with an emphasis on those that have ava ilable implementation in computer software. An example of the design and an alysis of a treatment trial in systemic lupus erythematosus with the triang ular test method of early stopping is also given.