How to effectively utilize imaging in disease-modifying treatments for osteoarthritis clinical trials: the radiologist's perspective.

Introduction: One of the reasons for failures of disease-modifying osteoarthritis drug clinical trials has been the radiography-based definition of structural eligibility criteria. Imaging, particularly MRI, has a critical role in planning and conducting clinical trials of osteoarthritis.Areas covered: A literature search was performed using keywords including 'osteoarthritis,' 'knee,' 'MRI,' 'intra-articular injection,' 'semiquantitative scoring,' 'clinical trial,' and other specific terms where relevant. The core concepts of using MRI in osteoarthritis clinical trials are explained focusing on knee osteoarthritis, including its role in determining patient eligibility and inclusion/exclusion criteria as well as outcome measures from the expert musculoskeletal radiologist's perspective. A brief overview of statistical analyses that should be deployed in clinical trials utilizing semiquantitative MRI analyses is discussed.Expert opinion: In order to increase chances to detect measurable efficacy effects, investigators should consider utilizing MRI from screening to outcome assessment. Recognition of several phenotypes of osteoarthritis helps in participant stratification and will lead to more targeted clinical trials. Inclusion and exclusion criteria need to be defined using not only radiography but also MRI. Correct intra-articular injection of investigational compounds is critically important if intra-articular drug delivery is required, and such procedure should be performed and documented using appropriate imaging guidance.