A Double Blind, Randomised, Placebo Controlled Parallel Group Study of Cannabis Based Medicine Extract (CBME), in the Treatment of Peripheral Neuropathic Pain Characterised by Allodynia.

Eligibility 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 his or her names to be notified to the Home Office for participation in this study 10. Willing to allow his or her General Practitioner and Consultant, if appropriate, to be notified of participation in the study 11. No cannabinoid use (cannabis, Marinolâ or Nabilone) at least 7 days before Visit 1 and willing to abstain from any use of cannabis during the study 12. Able (in the Investigator’s opinion), and willing to comply with all study requirements 1. History of schizophrenia, other psychotic illness, severe personality disorder or other significant psychiatric disorder other than depression associated with their underlying condition 2. Concomitant severe non-neuropathic pain or the presence of cancer related neuropathic pain or neuropathic pain resulting from diabetes mellitus 3. Known history of alcohol or substance abuse 4. Severe cardiovascular disorder, such as ischaemic heart disease, arrhythmias (other than well controlled atrial fibrillation), poorly controlled hypertension or severe heart failure 5. History of epilepsy 6. Female patient who is pregnant, lactating or planning pregnancy during the course of the study 7. Male patient who is currently receiving and unwilling to stop sildenafil (Viagra®) and unwilling to stop for the duration of the study 8. Regular levodopa therapy within 7 days of study entry 9. Significant renal or hepatic impairment 10. Known or suspected hypersensitivity to cannabinoids 11. Scheduled elective surgery or other procedures requiring general anaesthesia during the study 12. Terminal illness 13. Any other significant disease or disorder which, in the opinion of the Investigator, may either put the patient at risk because of participation in the study, or may influence the result of the study, or the patient’s ability to participate in the study 14. Travel outside the UK planned during the study 15. Donation of blood during the study 16. Patients who have participated in another research study in the past 12 weeks 17. Patients previously randomised into this study