Press Release

Porton Down, UK, 23 November 2009: GW Pharmaceuticals plc (GWP:AIM) announces that the results of a clinical study of Sativex® in the treatment of cancer pain have been published in the highly-regarded Journal of Pain and Symptom Management. The authors of the paper conclude that “this study shows that Sativex is efficacious for relief of pain in patients with advanced cancer pain not fully relieved by strong opioids”. Preliminary results from this study have previously been announced by GW.

The Journal of Pain and Symptom Management is the Official Journal of the American Academy of Hospice and Palliative Medicine, the National Hospice and Palliative Care Organization, and the U.S. Cancer Pain Relief Committee. The Sativex paper is published online and will appear in the print copy of the Journal in the coming months1.

The clinical study forms part of the ongoing development plan for Sativex in cancer pain, which represents the lead target indication for Sativex in the United States. A follow up Phase II/III cancer pain study is currently being carried out in collaboration with Otsuka Pharmaceutical Co. Ltd, GW’s US licensing partner for Sativex, with results due in Spring 2010.

The published multinational randomized placebo-controlled study included 177 patients with advanced cancer who had failed to gain adequate pain relief despite the use of strong opioids. This study compared the efficacy of Sativex (which comprises two cannabinoid extracts in which CBD (cannabidiol) and THC (delta 9 tetrahydrocannabinol) are the primary actives), a THC only extract formulation, and placebo.

The primary efficacy endpoint of the study was the difference in the mean improvement in pain scores between each of the active treatment groups and placebo. The results showed a significant improvement in the Sativex group compared with placebo (p=0.024). There was no significant improvement in the THC extract-treated group of patients compared with placebo. Overall, twice as many patients taking Sativex achieved a clinically meaningful improvement in their pain score of 30% or better compared with placebo (43% on Sativex vs 21% on placebo). The difference between the Sativex responder rate and that of placebo was highly statistically significant (p=0.006). The number of THC extract group responders was similar to placebo (23% vs. 21%). Most drug-related adverse events were mild/moderate in severity.

Professor Marie Fallon, Professor of Palliative Medicine, University of Edinburgh, said, “These are very promising results for Sativex in an area where there is a real need for new approaches to treatment. A number of patients with advanced cancer are not able to gain adequate pain relief from the existing medications, and the prospect that a new treatment may become available will be good news for many people”.

Dr Stephen Wright, GW’s R&D Director, said: “This placebo-controlled study shows that Sativex provides meaningful pain relief for people with advanced cancer who are suffering pain not adequately relieved by strong opioids. Sativex consists of two cannabinoid extracts with CBD and THC as the primary components, and the fact that the comparative THC extract medicine was not effective in relieving pain provides good evidence of the benefits which the presence of CBD confers on Sativex. We continue to progress the development of Sativex in this important area of high unmet medical need.”
 

Link to paper

For more information:
http://www.jpsmjournal.com/article/S0885-3924(09)00787-8/abstract