A mouth spray containing cannabinoids is effective in reducing pain in cancer patients who are still in pain despite using opioid medicines, according to a new study published in The Journal of Pain.
The oral mucosal spray known as nabixmols, which is marketed under the trade name Sativex, contains a formulation of cannabinoids, marijuana’s most active ingredients.
263 cancer patients with moderate to severe pain completed the study. They were divided into three groups and given nabixmols at low, medium and high doses for five weeks. Patients were asked daily about their pain levels and sleep patterns.
The study found a 26 percent improvement in pain in the group that received the low dosage of nabixmols. No significant improvement in pain was seen in patients in the high dosage group, who also didn’t tolerate the high dose well. Side effects included nausea and loss of cognitive function.
Patients receiving the low and medium doses of nabiximols said they slept better. Sleep disturbances are a common problem for patients with advanced cancer.
Opioid therapy is the standard treatment for cancer patients in pain. However, a significant number of patients continue to experience pain that isn’t controlled effectively at safe and tolerable opioid doses. In some cases, a co-administration of another analgesic may help, and researchers believe nabiximols could be used as an adjuvant therapy for pain – meaning it would be used in conjunction with opioids, not as an alternative to them.
“The finding that nabiximols has analgesic efficacy as add-on therapy for pain from advanced cancer that is poorly responsive to opioid therapy has great potential clinical relevance,” wrote lead author Russell K. Portenoy, MD, Chairman, Department of Pain Medicine and Palliative Care, Beth Israel Medical Center in New York City. “Based on the results of this dose-ranging study, nabiximols in a manageable dose range may prove to offer benefits to a very ill population with refractory pain. Confirmatory studies are strongly warranted.”
GW Pharmaceuticals, the British pharmaceutical company that makes Sativex (nabiximols), is seeking approval from the Food and Drug Administration to begin selling it in the U.S. for the treatment of cancer pain. Sativex is already approved in Canada, New Zealand and eight European countries for relieving muscle spasms for patients with multiple sclerosis.Canada also allows Sativex to be used for relief of neuropathic pain and advanced cancer pain.
The study was funded by Otsuka and GW Pharmaceuticals.