Salisbury, United Kingdom: Medicinal cannabis extracts improve patients' management of neuropathic pain better than standard analgesics, according to the results of a pair of clinical trials announced this week by British biotechnology firm GW Pharmaceuticals.
More than 250 patients with peripheral neuropathic pain (pain caused by damage to the nervous system) participated in the two placebo-controlled trials. Volunteers received either Sativex (an oral spray containing precise doses of the plant cannabinoids THC and CBD) or placebo.
In the first trial, patients suffering from severe pain characterized by allodynia (the occurrence of pain in response to normally non-painful stimulus) "obtained clinically important improvements in their management of pain and quality of sleep" after taking Sativex.
In the second trial, patients with diabetic neuropathy reported a 30 percent mean improvement in pain scores after taking Sativex, with one-third of patients reporting more than a 50 percent improvement in pain following the drug's administration.
"Even in this most difficult to treat population, Sativex has produced improvements over and above current treatments," the company stated in a press release.
Previous clinical trials of Sativex have shown the drug to reduce incidences of neuropathic pain associated with both Multiple Sclerosis and cancer. Sativex is currently available by prescription in Canada to treat MS-associated neuropathy, and on an 'import-only' basis in Spain and the United Kingdom.
Results of a US clinical trial assessing the use of inhaled cannabis to treat neuropathy are expected to be published this spring. Preliminary results presented in 2004 at the 11th Annual Retrovirus Conference in San Francisco demonstrated that inhaling cannabis was associated with a 30 percent reduction in pain in patients suffering from HIV-associated neuropathy.
Neuropathic pain affects an estimated one percent of the world's population and is typically unresponsive to both opioids and non-steroidal anti-inflammatory drugs such as ibuprofen.
For more information, please contact Paul Armentano, NORML Senior Policy Analyst, or visit: http://www.gwpharm.com.