Notice of Results

GW Pharmaceuticals to Report Q3 2014 Financial Results and Host Conference Call

on 6 August, 2014

London, UK, 30 July 2014: GW Pharmaceuticals plc (Nasdaq: GWPH, AIM: GWP, "GW" or "the Company"), a biopharmaceutical company focused on discovering, developing and commercializing novel therapeutics from its proprietary cannabinoid product platform, will announce on 6 August, 2014 its third quarter financial results for the period ending 30 June, 2014. GW will also host a conference call the same day at 1:00 p.m. BST (8:00 a.m. EDT).

Conference call information will be provided in the financial results press release. A replay of the call will also be available through the Company's website (www.gwpharm.com) shortly after the call.

About GW Pharmaceuticals plc

Founded in 1998, GW is a biopharmaceutical company focused on discovering, developing and commercializing novel therapeutics from its proprietary cannabinoid product platform in a broad range of disease areas. GW commercialized the world's first plant-derived cannabinoid prescription drug, Sativex®, which is approved for the treatment of spasticity due to multiple sclerosis in 25 countries outside the United States. Sativex is also in Phase 3 clinical development as a potential treatment of pain in people with advanced cancer. This Phase 3 program is intended to support the submission of a New Drug Application for Sativex in cancer pain with the U.S. Food and Drug Administration and in other markets around the world. GW has a deep pipeline of additional cannabinoid product candidates, including Epidiolex which has received from the FDA Fast Track Designation for the treatment of Dravet syndrome and Orphan Drug Designation from the FDA for the treatment of Dravet and Lennox-Gastaut syndromes, severe, drug-resistant epilepsy syndromes. GW's product pipeline also includes compounds in Phase 1 and 2 clinical development for glioma, ulcerative colitis, type-2 diabetes, and schizophrenia. For further information, please visit www.gwpharm.com.

Enquiries:

GW Pharmaceuticals plc

(Today) +44 20 3727 1000

Justin Gover, CEO

+44 1980 557000

Stephen Schultz, VP Investor Relations

+ 1 401 500 6570 or + 1 917 280 2424

FTI Consulting

Ben Atwell / Simon Conway / John Dineen (European media enquiries)

+ 44 20 3727 1000

Robert Stanislaro (US media enquiries)

+1 212 850 5657

Trout Group, LLC (US investor relations)

Todd James / Chad Rubin

 +1 646 378 2900

Peel Hunt LLP (UK Nominated Adviser and Broker)

James Steel / Oliver Jackson

 +44 20 7418 8900