Cannabis-based medicine could be on the UK market as early as 2003, according to GW Pharmaceuticals, the UK company developing cannabis-based prescription medicines, which this week released results from four Phase III clinical trials.
Preliminary results from GW's four randomised, double-blind, placebo-controlled Phase III trials show significant reductions in neuropathic (nerve-damage) pain, spasticity and sleep disturbance in patients with the nerve wasting disease multiple sclerosis, reported the company.
GW now intends to submit its first regulatory application to the UK's Medicines Control Agency early next year and subject to regulatory approval, expects to see a market launch of its first cannabis-based medicine in 2003.
Dr Geoffrey Guy, executive chairman of GW, said: "These preliminary Phase III results represent a major milestone in the pharmaceutical development of cannabis-based medicines. The performance of GW's medicine has exceeded our own expectations and holds out the prospect of providing a significant advance in the treatment of these most challenging of medical conditions. Subject to regulatory approval, we are now on track to deliver our first prescription medicine to the UK market next year."
GW's trials included approximately 350 patients and are part of one of the largest clinical programmes ever undertaken into the medicinal effects of cannabis.
The trials compared GW's THC:CBD medicine - a whole plant cannabis extract containing tetrahydrocannabinol (THC) and cannabidiol (CBD) as its principal components - to a placebo. The THC:CBD medicine was administered by means of a spray into the mouth.
The company said that the benefits seen in all four studies are even better than those obtained with standard prescription medicines (patients receiving both active and placebo medicines continued to take their standard prescription medicines during the trial).
Commenting on the trial results, Dr Philip Robson, GW medical director, said: "The results show statistically significant reductions in neuropathic pain, which is recognised as being difficult to treat and is often particularly distressing. There were also significant improvements in other symptoms in patients with MS, notably spasticity and sleep disturbance. In my opinion, it is this broad spectrum of activity, coupled with an excellent safety profile, which gives GW's cannabis-based medicine the potential to make a unique contribution towards improving the quality of life of patients with these chronic disabling diseases."
In addition to the four completed trials, GW has a further five Phase III trials in progress, examining other potential areas of benefit for cannabis-based medicines, including pain in cancer and spinal cord injury. These are expected to complete during 2003.
While cannabis is currently illegal in the UK, GW said it has received assurance from the UK government that if a prescription cannabis-based medicine was developed which meets the rigorous standards applied by the Medicines Control Agency, it will amend the legislation so that such a medicine is available for patients.
Reporting on the news, the Financial Times said that official data suggest that about 5 per cent of MS patients use cannabis, but some doctors say the figure is as high as 30 per cent. It also said that GW shares hit an 8-month high on Monday on speculation about the MS trial, although were down 5 per cent yesterday morning.
Full results of the study will be submitted for peer-review publication.