Medical imaging in pharmaceutical clinical trials: what radiologists should know.

The role of medical imaging in pharmaceutical clinical trials includes identification of likely responders; detection and diagnosis of lesions and evaluation of their severity; and therapy monitoring and follow-up. Nuclear imaging techniques such as PET can be used to monitor drug pharmacokinetics and distribution and study specific molecular endpoints. In assessing drug efficacy, imaging biomarkers and imaging surrogate endpoints can not only be more objective and faster to measure than clinical outcomes, but also allow small group sizes, quick results and good statistical power. In this article some basic principles of drug clinical development are explained. Study design, image reading and quantitative image processing in clinical trials with imaging components are discussed.