The emergence of concomitant trials for multiple investigational drug products for the treatment of rare diseases can pose significant challenges to effective drug development due to the limited number of patients worldwide with any given rare condition. The purpose of this guidance is to facilitate drug development in pediatric rare diseases. In particular, it discusses a new possible approach to enhance the efficiency of drug development in pediatric rare diseases using Gaucher disease as an example. This new approach consists of a controlled, multi-arm, multi-company clinical trial, which aims to facilitate the development of multiple drug products in a time­ efficient manner while minimizing the number of patients necessary to be treated with placebo.

The general principles presented should be viewed as a proposal only, and the principles underlying the proposal may be extended to other areas of drug development in rare diseases. Of note, the specific recommendations regarding drug development for Gaucher Disease apply only to systemic (i.e., non-neurological) manifestations of Gaucher disease in treatment-naïve patients with Type I and Type III phenotypes, across all the pediatric ages (i.e., up to 18 years of age).