A drug discovery case history of 'delta-9-tetrahydrocannabinol, cannabidiol'.

INTRODUCTION: Although the Cannabis sativa herb has been known for its therapeutic benefit for centuries, the interest in the clinical potential of cannabinoid-based drugs escalated after the discovery of the endocannabinoid system. The understanding of their actions at the molecular level indicates that the therapeutic applications of cannabinoids (plant-derived or synthetic) may be diverse. Several drugs containing cannabinoids are currently used in the therapy of emesis, pain and spasticity. AREAS COVERED: This drug discovery case history reviews the preclinical and clinical development of Sativex ('delta-9-tetrahydrocannabinol, cannabidiol'; nabiximols). Sativex is the first licensed phytocannabinoid-based drug approved, or in the process of approval, as therapy for indications such as MS-associated spasticity or chronic pain. Sativex contains a combination of two cannabinoids in approximately equal quantities (δ-9-tetrahydrocannabinol and cannabidiol) and is administered via an oromucosal pump spray, aiming at minimising psychotropic side effects and first pass effect. Pivotal clinical safety and efficacy data that led to Sativex's approval are discussed, as well as issues that have arisen with its clinical usage. EXPERT OPINION: Although pleiotrophic effects of cannabinoids may raise complex issues beyond their symptomatic effects, standardised pharmaceutical cannabinoids may constitute a useful addition to the pharmacotherapeutic armamentarium in chronic conditions insufficiently alleviated by existing drugs.