GWP.L Regulatory News (GWP)

17 Oct 2007 07:01

GW Pharmaceuticals PLC17 October 2007 New Published Study Shows Sativex(R) Provides Effective Long Term Treatment of MS Neuropathic Pain Porton Down, UK, 17 October 2007 - GW Pharmaceuticals plc (AIM: GWP) todayannounces that the Journal of Clinical Therapeutics has published the results ofa study which show that Sativex(R) provides effective long term treatment ofcentral neuropathic pain in Multiple Sclerosis (MS) and that these benefits areobtained without any evidence of tolerance (increase in dose) to the medicine(1). The open label extension trial results published follow a previously reportedshort term randomised controlled trial of the effect of Sativex for thetreatment of central neuropathic pain in MS. Improvements in the pain scores forthose patients who completed the extension trial showed sustained improvementover two years. At the end of the two year treatment period, the mean pain scorewas 2.9 (out of 10), a severity which can be described as mild. The mean painscore for all patients at entry into the initial short term controlled trial was6.5. Side effects reported during the two year period were in general mild ormoderate in severity. The mean number of sprays remained stable throughout thetwo year period, hence there was no evidence of tolerance (escalation in dose)with long term exposure and the study did not raise any additional safetyconcerns. The authors of the paper conclude that "Sativex is efficacious as a treatmentfor central pain due to multiple sclerosis in the long-term with no evidence oftolerance". Dr David Rog, first author of the paper and Consultant Neurologist at GreaterManchester Neurosciences Centre, who completed the study while at The WaltonCentre for Neurology and Neurosurgery, Liverpool, commented "This studydemonstrates that long-term use of Sativex provides sustained benefit in aroundhalf of patients with MS and central neuropathic pain. The improvement in thesepatients is obtained without the need for them to increase their dose." Sativex is approved as a prescription medicine in Canada for the relief ofcentral neuropathic pain in MS. This approval was based on a previously reportedstudy, which was published in the peer-reviewed journal, Neurology, which showedthat Sativex was significantly superior to placebo in reducing pain (p=0.005)and sleep disturbance (p=0.003) (2). This previous study showed Sativex to beeffective in short-term use, whereas this newly-published study confirms thatits effect in reducing pain and improving sleep is maintained over a prolongedperiod. In addition to these completed trials, GW has recently completed patientrecruitment in an additional pivotal Phase III trial in MS neuropathic pain. Thestudy has recruited 339 patients and is GW's largest clinical trial to date. Theduration of treatment in the study is 14 weeks and headline results are expectedin H1 2008. Dr Stephen Wright, GW's R&D Director, said "The results announced today confirmthat Sativex is able to provide substantial relief from pain for a long periodof time to patients who have previously failed to obtain benefit from otheravailable treatments. We believe that this study shows, in a setting thatreflects normal clinical practice, that Sativex is able to meet a real medicalneed. The results add to what we know from short-term clinical trials, and welook forward to seeing the results of our ongoing pivotal study in the samecondition in the first half of next year." Enquiries:GW Pharmaceuticals plc Today: +44 (0)20 7831 3113Dr Geoffrey Guy, Executive ChairmanJustin Gover, Managing DirectorDr Stephen Wright, R&D Director Financial Dynamics Tel: +44 (0)20 7831 3113David Yates, Ben Atwell Notes to Editors Sativex(R) Sativex (THC:CBD), an endocannabinoid system modulator, is derived from wholeplant extracts of two specifically bred cannabis plant varieties. The extractsare combined to produce a standardised formulation containing two majorcomponents of cannabis, the cannabinoids D9-tetrahydrocannabinol (THC) andcannabidiol (CBD). Sativex is formulated into a pump action oromucosal (mouth) spray designed forself-administration by the patient. This formulation allows for flexibledosing, ideal for the variable nature of MS. Each spray of Sativex delivers afixed dose of 2.7mg THC and 2.5mg CBD. Sativex was generally well tolerated inthe study. Neuropathic Pain in MS Pain is a common symptom of MS occurring in up to 86 per cent of people with MS.(3) Neuropathic or nerve pain can occur spontaneously or can be provoked bytouch, temperature or movement. It is estimated that 50 per cent of people withMS suffer from chronic neuropathic pain (4,5,6). The most common descriptions ofneuropathic pain are of freezing, cold or burning sensations usually of thelimbs and most often of the lower extremities (7). Many individuals withneuropathic pain respond inadequately to current treatment options (8,9). GW Pharmaceuticals plc GW was founded in 1998 and listed on the AIM, a market of the London StockExchange, in June 2001. Operating under license from the UK Home Office, thecompany researches and develops cannabinoid pharmaceutical products thatalleviate pain and other neurological symptoms in patients who suffer fromserious ailments. GW has assembled a team of over 100 scientists with extensive experience indeveloping both plant-based prescription pharmaceutical products and medicinescontaining controlled substances. GW occupies a world leading position incannabinoids and has developed an extensive international network of the mostprominent scientists in the field. For further information, please visitwww.gwpharm.com Footnotes 1. Rog D, Nurmikko T, Young C. Oral D-9 Tetrahydrocannabinol/ cannabidiol for neuropathic pain associated with multiple sclerosis: an open label, uncontrolled, 2 year extension trial. Clinical Therapeutics. 2007: 9; 2068-2079 2. Rog D, Nurmikko T, et al. Randomized controlled trial of cannabis medicine in central pain due to multiple sclerosis. Neurology. 2005;65:812-819 3. Ehde DM et al. Multiple Sclerosis 2003; 9; 605-611. 4. Archibald CJ, et al. Pain 1994; 58:89-93. 5. Sketris IS, et al. Clinical Therapeutics 1996; 18(2):303-318. 6. Moulin DE, et al. Neurology 1988;38:1830-1834. 7. Multiple Sclerosis International Federation www.msif.org/print.rm?id=10188 8. Harden N and Cohen M. Journal of Pain Symptom Management 2003; 25 (5 Suppl): S12-S17. 9. New Directions in Neuropathic Pain: Focusing Treatment on Symptoms and Mechanisms. Royal Society of Medicine Press Ltd.: 2000. This information is provided by RNS The company news service from the London Stock Exchange