The purpose of this study is to evaluate the efficacy of Sativex® compared with placebo in relieving peripheral neuropathic pain associated with allodynia.
INTERVENTION: THC:CBD, 1:1 and placebo CONDITION: Peripheral neuropathic pain, characterised by allodynia ; Signs and Symptoms ; Pain, not elsewhere classified PRIMARY OUTCOME: Efficacy in relieving peripheral neuropathic pain after 5 weeks of treatment SECONDARY OUTCOME: 1. Qualitative aspects of pain as reported the Neuropathic Pain Scale (NPS); 2. The physical and psychological effects of pain using measures of sleep disturbance, the Pain Disability Index (PDI) and General Health Questionnaire (GHQ‐12); 3. Patient?s cognitive function using the Brief Repeatable Battery of Neuropsychological tests (BRB‐N); 4. Patient perception of change in allodynia and pain on movement after 5 weeks of treatment; 5. Tolerability of CBME using the adverse event profile, electrocardiogram (ECG), clinical laboratory tests and vital signs INCLUSION CRITERIA: 1. Patient or legal representative is willing and able to give informed consent for participation in the study (if the patient is unable to read or to sign the document, consent procedures as detailed in the Declaration of Helsinki must be followed) 2. Male or Female, aged 18 years or above 3. Chronic peripheral neuropathic pain of at least 6 months duration 4. Presence of mechanical allodynia within the territory of the affected nerve(s) 5. Evidence of sensory change in the affected nerve by simple clinical tests 6. Pain with a severity score of 4 or more on at least 4 completed BS‐11 scores in the baseline week 7. Stable dose of current analgesic medication for at least 2 weeks prior to study entry 8. Female patients of child bearing potential and male patients whose partner is of child bearing potential are willing to ensure that they or their partner use effective contraception during the study and for 3 months thereafter 9. Willing for h
Cannabinoids are known to have analgesic properties. We evaluated the effect of oro-mucosal sativex, (THC: CBD), an endocannabinoid system modulator, on pain and allodynia, in 125 patients with neuropathic pain of peripheral origin in a five-week, randomised, double-blind, placebo-controlled, parallel design trial. Patients remained on their existing stable analgesia. A self-titrating regimen was used to optimise drug administration. Sixty-three patients were randomised to receive sativex and 62 placebo. The mean reduction in pain intensity scores (primary outcome measure) was greater in patients receiving sativex than placebo (mean adjusted scores -1.48 points vs. -0.52 points on a 0-10 Numerical Rating Scale (p=0.004; 95% CI: -1.59, -0.32). Improvements in Neuropathic Pain Scale composite score (p=0.007), sleep NRS (p=0.001), dynamic allodynia (p=0.042), punctate allodynia (p=0.021), Pain Disability Index (p=0.003) and Patient's Global Impression of Change (p<0.001) were similarly greater on sativex vs. placebo. Sedative and gastrointestinal side effects were reported more commonly by patients on active medication. Of all participants, 18% on sativex and 3% on placebo withdrew during the study. An open-label extension study showed that the initial pain relief was maintained without dose escalation or toxicity for 52 weeks.
The purpose of this study is to evaluate the efficacy of Sativex® compared with placebo in relieving peripheral neuropathic pain associated with allodynia.
