The FDA and designing clinical trials for chronic cutaneous ulcers

Treatment of chronic wounds can present a challenge, with many patients remaining refractory to available advanced therapies. As such, there is a strong need for the development of new products. Unfortunately, despite this demand, few new wound-related drugs have been approved over the past decade. This is in part due to unsuccessful clinical trials and subsequent lack of Food and Drug Administration (FDA) approval. In this article, we discuss the FDA approval process, how it relates to chronic wound trials, common issues that arise, and how best to manage them. Additionally, problems encountered specific to diabetic foot ulcers (DFU) and venous leg ulcers (VLU) are addressed. Careful construction of a clinical trial is necessary in order to achieve the best possible efficacy outcomes and thereby, gain FDA approval. How to design an optimal trial is outlined.

► Few wound care drugs have been approved over the past decade, which can be attributed to high cost of development and/or poor clinical trial design.
► Discussion of FDA approval process, Phase I–IV trials and the differences in approval for drug, devices, biologics and combinations.
► Critical issues exist in including design of inclusion/exclusion criteria, standard of care therapy, infection control, and efficacy outcomes.
► Common pitfalls include underestimating time and cost, overestimating subject enrolment, and allowing market considerations to guide design.