Clinical Trial Update

 

TIDMGWP 
 
RNS Number : 7480N 
GW Pharmaceuticals PLC 
24 February 2009 
 

POSITIVE RESULTS IN RANDOMIZED WITHDRAWAL SATIVEXSTUDY CONFIRM LONG TERM 
EFFICACY IN MS SPASTICITY 
 
 
Porton Down, UK, 24 February 2009: GW Pharmaceuticals plc (GWP:AIM) announces 
positive results from a placebo-controlled randomized withdrawal study of 
Sativex  in patients with spasticity due to Multiple Sclerosis (MS). This study 
was performed following regulatory guidance from the UK regulatory authority 
(MHRA) and provides evidence of long term efficacy to be included as part of the 
forthcoming European regulatory submission planned for Q2 09. 
 
 
Separately, GW remains on track to report results of its Phase III MS Spasticity 
trial towards the end of Q1 09. 
 
 
This randomized withdrawal study evaluated 36 MS patients with spasticity who 
had previously been taking Sativex on prescription. The mean duration of prior 
Sativex prescription use was 3.6 years. The patients were randomized to Sativex 
or placebo for 4 weeks in a double-blinded manner. During the randomized period, 
patients were not permitted to adjust their dose. The purpose of this blinded 
4-week "randomized withdrawal" study was to assess the maintenance of spasticity 
relief in patients who remain on Sativex versus those who switch to placebo. 
 
 
The prospectively defined primary efficacy endpoint of the study - the time to 
treatment failure - was statistically significantly in favour of Sativex 
(p=0.013). The difference between Sativex and placebo was also significant for 
the patient global impression of change (p=0.017) and the carer 
functional-ability global impression of change (p=0.001). This means that the 
carer recognised that the patient's spasticity became worse when they stopped 
taking Sativex - thus providing independent verification of the primary 
endpoint. 
 
 
There was no evidence of a withdrawal syndrome in those patients who stopped 
Sativex, despite a very prolonged period on the medicine. Overall, there was a 
similar frequency and severity of adverse events in both the Sativex and placebo 
groups of patients, with more than 85% of such events being deemed mild or 
moderate in severity. 
 
 
In September 2008, GW reported positive results from a placebo-controlled 
randomized withdrawal study of Sativex in patients with neuropathic pain due to 
MS. The results reported today are from a study with a similar design but in 
patients with a different MS symptom. Taken together, these studies show that 
the efficacy of Sativex in the treatment of both neuropathic pain and spasticity 
due to MS is maintained in long-term use. 
 
 
Dr Stephen Wright, GW's R&D Director, said: "This placebo-controlled study shows 
that Sativex provides meaningful long term efficacy for people with spasticity 
due to MS. These results will be an important new feature of the efficacy and 
safety data to be submitted in our next regulatory application. Separately, I am 
able to confirm that the pivotal Phase III trial in MS spasticity is on track to 
report results towards the end of Q1 09 and a regulatory submission is targeted 
for Q2 09." 
Enquiries: 
 
 
+--------------------------------------------+-----------------------------------------+ 
| GW Pharmaceuticals plc                     |               (Today) + 44 20 7831 3113 | 
+--------------------------------------------+-----------------------------------------+ 
| Dr Geoffrey Guy, Executive Chairman        |           (Thereafter) + 44 1980 557000 | 
+--------------------------------------------+-----------------------------------------+ 
| Justin Gover, Managing Director            |                                         | 
+--------------------------------------------+-----------------------------------------+ 
|                                            |                                         | 
+--------------------------------------------+-----------------------------------------+ 
| Financial Dynamics                         |                       + 44 20 7831 3113 | 
+--------------------------------------------+-----------------------------------------+ 
| David Yates / Ben Atwell                   |                                         | 
+--------------------------------------------+-----------------------------------------+ 
 
 
 
 
Notes to Editors 
 
 
Time to Treatment Failure Analysis 
The primary endpoint in the study was a time to treatment failure analysis. In 
the context of this study, a time to treatment failure means either (i) time to 
the patient experiencing a clinically meaningful worsening of their spasticity 
(as measured on a Numeric Rating Scale) or (ii) a decision to withdraw from the 
study (and to go back to their prescription Sativex). 
 
 
Sativex Prescription Use 
Sativex is approved and marketed in Canada for the treatment of cancer pain and 
MS neuropathic pain. In addition, Sativex is available on prescription in the UK 
on a "named patient" basis and has to date been exported to 22 countries around 
the world. 
 
 
Sativex and MS Spasticity 
Spasticity (spasms and stiffness) is one of the most common symptoms of MS 
occurring in as many as three-quarters of people with MS. Spasticity can affect 
many aspects of daily life, such as walking and sitting. Sativex aims to treat 
high need patients who have previously failed to gain adequate benefit from 
currently available anti-spasticity treatments 
 
 
GW has a body of clinical data in approximately 700 patients with MS spasticity, 
including two pivotal Phase III trials as well as two supportive trials. A third 
Phase III trial, involving 575 patients, is due to report results in late Q1 
2009. 
 
 
Following these results, GW intends to submit a regulatory application in Q2 09 
in selected European countries. Upon approval, Sativex will be exclusively 
marketed in the UK by Bayer HealthCare and in the rest of Europe by Laboratorios 
Almirall, S.A. 
 
 
Sativex and Cancer Pain 
Over one-third of patients with cancer, and more than three-quarters of those 
with advanced disease, have chronic pain.  Currently available opioid therapies 
do not yield sufficient relief in a substantial proportion of these patients and 
there is a clear need for new treatments. 
 
 
Cancer pain is the lead indication for the development of Sativex in the United 
States. GW has completed a positive Phase II cancer pain study in Europe in 177 
patients and is now carrying out a 336 patient Phase IIb/III study in 
collaboration with its partner, Otsuka Pharmaceutical Co. Ltd. Upon approval, 
Sativex will be exclusively marketed in the US by Otsuka. 
 
 
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. 
 
 
 
This information is provided by RNS 
            The company news service from the London Stock Exchange 
   END 
 
 MSCEAKADAAANEFE