Working with the US Food and Drug Administration: Progress and timelines in understanding and treating patients with eosinophilic esophagitis

The article by Fiorentino et al. (1) summarizes recent progress in the development of therapeutics for the emerging allergic disorder eosinophilic esophagitis (EoE) (2). The authors present an encouraging picture of an ongoing partnership between the Food and Drug Administration (FDA) and a number of stakeholders, including patients, families, advocacy organizations, a network of physician investigators (The International Group of Eosinophilic Disease Researchers [TIGERS]), academicians, researchers and the pharmaceutical industry who all focus on EoE. A basic premise of the article is the urgent need to develop validated and meaningful Clinical Outcome Assessment (COA) tools such as Patient Related Outcomes (PRO)(3). The lack of these questionnaires are described as currently hindering key progress in understanding and effectively treating this emerging disease. We agree that such tools would likely advance the field. The authors suggest that we are in the early stages of understanding EoE disease pathogenesis and clinical description, but we would like to touch on the tremendous progress that has actually been made over the past decade, including effective clinical trials that have been carried out despite the limitations in currently available COA and PRO tools. We present the concern that the search for a COA tool and its eventual employment have the potential to slow drug development; thus, caution is warranted so as not to become solely focused on COA tools for regulatory product approval.