Clinical trials: curing a critical deficiency in metabolic medicine.

The treatment of rare disorders is often driven by experience and expert opinion rather than formal clinical trials because of the significant barriers in place to conducting traditional random, placebo controlled, national studies. Dr. Doug Kerr graphically illustrates these problems in the treatment of inborn errors of mitochondrial oxidative phosphorylation as reviewed elsewhere in this issue. New models and additional funding for studying the ultra rare diseases that are the purview of metabolic medicine are desperately needed to move the field forward in an evidence-based fashion. In this commentary, the challenges associated with conducting clinical trials in ultra-rare disorders are discussed and potential solutions suggested. Copyright (c) 2009 Elsevier Inc. All rights reserved.