GW Pharmaceuticals was founded in 1998 and listed on the AIM, a market of the London Stock Exchange, in June 2001. GW is licensed by the UK Home Office to work with a range of controlled drugs for medical research purposes. The Group's lead programme is the development of a product portfolio of cannabinoid prescription medicines , including Sativex® Oromucosal Spray, to meet patient needs in a wide range of therapeutic indications.

GW’s lead product, Sativex®, is approved and marketed in Canada for the relief of neuropathic pain in Multiple Sclerosis (MS) and also as adjunctive analgesic treatment in adult patients with advanced cancer who experience moderate to severe pain during the highest tolerated dose of strong opioid therapy for persistent background pain. Each of these approvals was secured under the Notice of Compliance with Conditions (NOC/c) policy. Sativex® is also in late stage clinical development in Europe and the United States.

GW has entered into three licensing agreements for Sativex® – with Bayer HealthCare in the UK and Canada, with Almirall in Europe (excluding UK) and with Otsuka Pharmaceutical Co. Ltd in the United States.

GW has assembled a team of over 100 scientists with extensive experience in developing both plant-based prescription pharmaceutical products and medicines containing controlled substances. GW maintains in-house control over all aspects of the cannabinoid product development process - botanical research, cultivation, extraction, formulation into drug delivery technologies, clinical trials and regulatory affairs. All products are administered through pharmaceutically-appropriate delivery systems.

GW occupies a world leading position in cannabinoids and has developed an extensive international network of the most prominent scientists in the field. With a view to encouraging exploratory research and identifying future product opportunities, GW established in March 2002 a separate division called the Cannabinoid Research Institute or “CRI”. The CRI aims to link industry and academia in conducting exploratory research which it is hoped will lead to the identification of new indications for cannabinoid medicines and greater understanding of the mechanism of action of cannabinoids. In mid 2007, the CRI’s activities were significantly expanded through the establishment of a global cannabinoid research agreement with Otsuka.