Draft Guidance on Slowly Progressive, Low-Prevalence Rare Diseases with Substrate Deposition That Results from Single Enzyme Defects: Providing Evidence of Effectiveness for Replacement or Corrective Therapies

Today the U.S. Food and Drug Administration (FDA) is making available a draft guidance Slowly Progressive, Low-Prevalence Rare Diseases with Substrate Deposition That Results from Single Enzyme Defects: Providing Evidence of Effectiveness for Replacement or Corrective Therapies.  FDA is issuing this draft to provide guidance to sponsors on the evidence necessary to demonstrate the effectiveness of investigational drugs or new drug uses intended for slowly progressive, low-prevalence rare diseases that are associated with substrate deposition and are caused by single enzyme defects. This guidance applies only to low-prevalence rare diseases with well-characterized pathophysiology in which changes in substrate deposition can be readily measured in relevant tissue(s). 

This draft guidance is also part of the Center for Drug Evaluation and Regulation’s pilot program to provide industry and other stakeholders with streamlined guidance documents on policy, endpoints, and other information important to drug development. Guidances in the pilot are intended to be concise and targeted in scope and free of non-essential language, lengthy scientific narrative, or information already available in other guidance.

More information on FDA’s efforts pertaining to rare diseases is available on FDA’s Office of Orphan Products Development and CDER’s Rare Diseases Program websites.