MHRA requires 'further clinical trials' but Sativex launched in Canada
GW Pharmaceuticals has received regulatory approval from Health Canada for Sativex, which is now available by prescription through Canadian pharmacies as an adjunctive treatment for symptomatic relief of neuropathic pain in adults with multiple sclerosis (MS). In April 2005, Canada became the first country in the world to approve Sativex, which the company says is an effective and safe cannabis derived prescription medicine.
GW Pharmaceuticals has received regulatory approval from Health Canada for Sativex, which is now available by prescription through Canadian pharmacies as an adjunctive treatment for symptomatic relief of neuropathic pain in adults with multiple sclerosis (MS). In April 2005, Canada became the first country in the world to approve Sativex, which the company says is an effective and safe cannabis derived prescription medicine.
Sativex is manufactured in the UK by GW and its contract manufacturing partners. The product is being marketed in Canada by Bayer HealthCare, Pharmaceuticals Division, GW's marketing partner.
The product is administered through a spray pump under the tongue or on the inside of the cheek, providing reliable, self-administered pain relief. Its principal active cannabinoid components are delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Sativex is a pharmaceutical product standardised in composition, formulation, and dose. While there is no complete cure for MS or neuropathic pain, a double-blind placebo controlled parallel group study demonstrated that Sativex provided significantly greater pain relief than placebo. Sativex also significantly reduced pain-related sleep disturbance.
MS is a disease of the central nervous system and is the most common neurological disease affecting young adults in Canada. It is estimated that 50 per cent of people with MS suffer from chronic neuropathic pain1,2,3. Approximately 50,000 Canadian men and women have the disease4.
However, following GW's appeal against the Medicines and Healthcare products Regulatory Agency's (MHRA), December 2004 decision that a further clinical study in Multiple Sclerosis (MS) Spasticity would be required prior to the grant of a UK product licence for Sativex, the Medicines Commission met in mid May and received a presentation supporting the approval of Sativex by a number of the UK's leading experts in the field. The appeal was also attended by MS patient representative organisations.
At a recent meeting with senior officials at the MHRA, GW was informed that the Medicines Commission has declined GW's appeal - the Commission has determined that the evidence of efficacy of Sativex in MS Spasticity is not yet sufficiently compelling. In December 2004, GW announced its intention to start an additional MS Spasticity study in parallel to the Medicines Commission process. This 280 patient study has now commenced and is due to report results in Spring 2006.
Professor Mike Barnes, president of the World Federation of Neuro-rehabilitation, chairman of the Royal College of Physicians Rehabilitation Committee and Professor of Neurological Rehabilitation at the University of Newcastle-upon-Tyne, said: 'It is my view that there is excellent clinical evidence to support the regulatory approval of Sativex in the UK. I am very disappointed that the Medicines Commission did not follow the recommendation of myself and other leading experts in the treatment of MS. People with MS have considerable unmet medical needs and I am deeply saddened that the regulators do not yet feel in a position to licence this important product.' The MHRA's position relates solely to the indication of MS Spasticity.
GW will continue to progress its research programme for the use of Sativex in a range of indications. In addition to its MS programme, GW has reported positive Phase III data in Neuropathic Pain and two further neuropathic pain trials are commencing in support of a future regulatory filing in this indication. In addition, having reported a positive Phase III Cancer Pain trial earlier this year, the company is now planning an additional trial which will provide a registration package for this indication also.
GW says it remains in a strong financial position, with net cash balances of £16.2m at end of May 2005.
Dr Geoffrey Guy, executive chairman, said: 'We are disappointed that the UK regulators consider that the efficacy data is not yet sufficiently compelling to make Sativex available to UK patients for the relief of MS Spasticity. Our view, which is shared by prominent experts in the field, is that the existing clinical data shows that Sativex provides an important new treatment option for patients with MS. We know that UK patients will share our disappointment at the decision of the regulators to delay its introduction.
'It is clear from our discussions with the regulatory authority that they recognise the promising results seen to date and they have expressed a desire to provide constructive advice to GW as to how the regulatory requirements may best be met.
'While today's news is disappointing, the fundamentals for the company remain strong. Sativex is now available on prescription to MS patients in Canada, and we have produced a wealth of positive clinical trials data, including seven Phase III trials and have a range of further trials underway. GW also retains its world leading position in cannabinoid science. The setback will only serve to reinforce our determination to bring this important and innovative new medicine to the UK market.'