Notification of Results

21 October 2010

Porton Down, UK, 21 October 2010: GW Pharmaceuticals plc (AIM: GWP) will be announcing its preliminary financial results for the year end 30 September 2010 on Tuesday 23 November 2010.

Enquiries:

Financial Dynamics	020 7831 3113
Ben Atwell / John Dineen

Notes to Editors

About GW

GW was founded in 1998 and listed on the AIM, a market of the London Stock Exchange, in June 2001. Operating under license from the UK Home Office, the company researches and develops cannabinoid pharmaceutical products for patients who suffer from a range of serious ailments, in particular multiple sclerosis and cancer pain. GW has assembled a large in-house scientific team with expertise in cannabinoid science as well as experience in the development of both plant-based prescription pharmaceutical products and medicines containing controlled substances. GW occupies a world leading position in cannabinoids and has developed an extensive international network of the most prominent scientists in the field. For more information, visit www.gwpharm.com