While numerous herbal preparations have been used to treat human illnesses for extensive period of time in many different cultures, very few have been subject to rigorous clinical testing of modern scientific standards. To facilitate more clinical development of new drugs from botanical sources, the US FDA has published a draft Guidance for Industry: Botanical Drug Products in August 2000.
www.fda.gov/cder/guidance/1221dft.pdf. For herbal preparations with substantial marketing history, past human experiences may be taken into consideration for safety assessment and clinical studies may be initiated with less extensive product characterization and non-clinical testing. However, efficacy of almost all herbal products remains to be established with clinical trials that should be no different from those required for non-botanical new drugs. The objective of the regulatory approach is to confer the same degree of confidence in the clinical effectiveness of herbal medicines as that of modem non-botanical drugs. In this presentation, basic principles of clinical trial in all new drug development will be described, and unique issues related to studies of herbal medicines discussed.