Synthetic cannabinoid could treat pain in diabetes patients
medwireNews: Oral synthetic cannabinoid nabilone may be effective for treating diabetic peripheral neuropathic pain (DPN), a study shows.
The 12-week double-blind placebo-controlled phase III clinical study of 60 patients with DPN showed that nabilone 1-4 mg per day significantly improved DPN symptoms, sleep quality, and overall quality of life. Nabilone is currently approved by Health Canada and the US Food and Drug Administration for the treatment of nausea in chemotherapy patients in Canada.
"This is a good option to help treat nerve pain due to diabetes, with very few side effects," commented Cory Toth (University of Calgary, Alberta, Canada) in a press statement.
Independent expert Mark Ware (McGill University Health Centre, Montreal, Quebec, Canada) added: "This study is a further demonstration of the potential medical benefits of cannabinoids in a difficult pain condition. Dr Toth and his team have conducted a solid trial, which although small, validates our clinical experience.
"This study gives physicians support to consider further options in treating this devastating chronic pain disorder," he continued.
The study involved DPN patients who scored 4 or more on a pain scale of 0-10, continued regular pain medications, and were administered single-blinded adjuvant nabilone for 4 weeks. The 26 individuals who achieved an improvement in pain relief of 30% or more were then randomized and treated with either flexible-dose nabilone (1-4 mg/day) or placebo (n=13) in a further 5-week double-blind treatment period, with 30% (n=11) deemed run-in phase nabilone nonresponders.
The team showed that after a 5-week double-blind treatment period, nabilone run-in phase responders showed a significant improvement in endpoint neuropathic pain, at a mean reduction of 1.27 - on a numerical pain rating scale from 0-10 - compared with placebo. The mean endpoint nabilone dose was 2.85 mg per day, consisting of one patient taking 1 mg per day, six patients taking 2 mg per day, and six patients taking 4 mg per day.
Nabilone responders also showed significant improvements from baseline on the anxiety subscale of the Hospital Anxiety and Depression Scale, the Medical Outcomes Study sleep scale problems index, and the European Quality of Life-5-Domains index score.
As reported in Pain, nabilone run-in phase responders reported a significantly greater global endpoint improvement in pain with nabilone than with placebo, at 100% versus 31%.
The analysis also showed that medication-related confusion led to discontinuation in two of the 37 participants receiving single-blind nabilone treatment.
The authors acknowledge that the trial was concluded earlier than expected due to insufficient funding, and due to this they did not achieve the estimated total of 44 participants in the second randomized phase of the study.
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By Piriya Mahendra, medwireNews Reporter