Clinical trials design: structure modifying agents for osteoarthritis. Future guidelines: areas for development.

Clinical trials guidelines should offer evidence-based recommendations, and, where evidence is lacking or absent, should reflect the considered opinion of experts in the field. Recent OsteoArthritis Research Society International (OARSI) guidelines encompass these principles and are the result of a Task Force Workshop involving representatives from academia, regulatory authorities and industry. Areas for continued development for trials of Structure Modifying Osteoarthritis Drugs (STMOAD) include patient selection, study duration, sample size estimation, outcome assessment, imaging, response definition and pharmoeconomics. As developments occur in these and related areas, guideline documents will require revision to reflect this evolution. Notwithstanding these issues, there is opportunity to identify STMOAD class agents using current methodologies. Copyright 1999 OsteoArthritis Research Society International.