The right to try

N-of-1 Clinical Trials: A Scientific Approach to Personalized Medicine for Patients with Rare Retinal Diseases Such as Retinitis Pigmentosa

N-of-1 trials are randomized, prospective, controlled, multiple crossover trials in a single patient. Effects of one or more treatments are studied by following individual patients who receive alternative treatments (eg, therapeutic intervention). Such trials may provide a path to assess treatments for rare diseases with rigor equal to or greater than that afforded by parallel group randomized clinical trials provided that the condition is reasonably stable during the trial and has a sign/symptom that responds reversibly to the therapy and that can be measured repeatedly. In this article, the authors propose that N-of-1 trials may improve the feasibility and affordability of clinical trials for patients with rare inherited retinal diseases.

The permuted locus trial--Well suited for emerging pathogens?

The recent Ebola virus epidemic was waning by the time stakeholders were ready to field vaccines for testing but an evidence-based response to a novel pathogen will surely be required again. Here, we present a design for such a randomized controlled trial. The permuted locus trial was originally intended for studying the influence of water wells on trachoma. While outcomes can be measured in individuals, neither individuals nor groups are themselves randomized to arms, just potential well-sites, or in the case of an epidemic, index cases. The permuted locus trial may be used when classic individual and cluster-randomized trial design and analyses may not be optimal.