Notice of Results

GW Pharmaceuticals to Report Q2 2014 and Half Year Financial Resultsand Host Conference Call on 7 May, 2014

London, UK, 29 April 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 7 May, 2014 its second quarter and half year financial results for the period ending 31 March, 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. 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 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

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