GW Reports Highly Statistically Significant Results in Sativex Pivotal Phase III Study in MS Spasticity

This Phase III study used an enriched design whereby 573 patients initially received Sativex for 4 weeks in a single blind manner (Phase A), following which Sativex responders (n=241) were randomized to continue on Sativex or switch to placebo for a further 12 weeks in a double-blinded manner (Phase B). During the randomized period, patients were not permitted to adjust their dose. This study is the largest study GW has undertaken and recruitment was achieved in just ten months using 52 hospital sites in five countries - UK, Spain, Italy, Czech Republic and Poland.

The prospectively defined primary efficacy endpoint of the study - the difference between the mean change in spasticity severity of Sativex vs Placebo in Phase B - was highly statistically significantly in favour of Sativex (p=0.0002). The numeric difference between the two groups as measured on a Numeric Rating Scale was 0.84 units from a baseline of 3.89, greater than that achieved in previous studies. The difference between Sativex and placebo was also significant for a number of secondary endpoints. 74% of Sativex patients achieved an improvement of greater than 30% in their spasticity score over the entire study versus 51% on placebo (p=0.0003). In addition, statistically significant improvements were also seen in spasm frequency (p=0.005), sleep disturbance (p<0.0001), patient global impression of change (p=0.023), and physician global impression of change (p=0.005).

The study provides further evidence of Sativex's reassuring safety profile. The adverse event data in this study was superior to previous Sativex studies - an improvement which resulted from the modified dose titration regimen employed in the study.

Following these positive results, GW will submit a regulatory application in Q2 09 in the UK and, subject to discussion with Almirall, other selected European countries. Upon approval, Sativex will be marketed exclusively in the UK by Bayer HealthCare and in the rest of Europe by Almirall.

Dr Stephen Wright, GW's R&D Director, said: "This Phase III study is a resounding success and provides further evidence that Sativex provides meaningful efficacy for people with spasticity due to MS. In the last six months, GW has reported three positive Sativex studies incorporating a design modified from previous studies and we are delighted that this new approach is producing such consistent positive results. We will file a European regulatory submission in Q2 09 and look forward to progressing the review during 2009."

Milestone Payment

GW also announces today that it has signed an amendment to the Sativex licence agreement with Almirall. This amendment provides for the potential milestone payment to be received following this study result to reach £8m. The £8m milestone will become due upon Almirall electing to include a country within their licensed territory (Europe excluding UK) as part of the forthcoming regulatory submission to the UK. This decision is expected to be made within the next month.

Justin Gover, GW's Managing Director, said, "GW has a history of maintaining a strong financial position and this increased potential milestone payment represents an attractive opportunity to further consolidate this position. We are delighted by the ongoing support and enthusiasm of our licensing partners for the commercial potential of Sativex."

There will be a conference call for analysts today at 2.30pm. Analysts should contact Juliet Edwards at Financial Dynamics on 020 7269 7125 for details. There will be a live audio web cast of this call which will be accessible on the press releases page in the investor relations section of the GW website (www.gwpharm.com). A recording of this meeting will be available on the GW website later today.