Novel Treatment Option for Neuropathic Pain

Inclusion Criteria: * Signed informed consent and anticipated compliance. * Pain defined as "definite" neuropathic pain, according to the Special Interest Group on Neuropathic Pain guidelines or defined as "probable" NP, according to the guidelines, if the confirmatory test was a positive diagnostic test. Complex regional pain syndrome can be included despite lack of an offending lesion, as long as the "Budapest criteria" are fulfilled * Neuropathic Pain associated with compressive nerve states (including failed surgery) or CRPS (according to the "Budapest criteria") * PainDETECT score of at least 13 with average pain intensity of at least 6 /10 over the last four weeks. In addition, a painDETECT pattern indicating that the underlying neuropathic pain is constantly present. * Worst pain intensity higher than 6 for five of seven days during the screening phase, according to Brif Pain Inventory. * The patient should be able to distinguish between the neuropathic pain and other pain conditions, including elements of nociceptive pain caused by the same disease process. * Neuropathic pain duration of between six and thirty months, deemed chronic and likely to be irreversible by clinical history and findings. * No new or increased neuropathic pain treatment for the last four weeks. * Standard medical treatments for the patients' underlying condition or neuropathic pain must have been considered or tried and must, according to the opinion of the referring or a consulted pain specialist, be judged to be inappropriate or of insufficient potential efficacy. * Referring physician agreement to follow up the patient after study completion according to the best possible and available pain treatment and care. * Women of childbearing potential and men must use an acceptable method of contraception throughout the study, and for 30 days after the last study drug administration. * Negative pregnancy test within 7 days before each treatment period where appropriate. * White blood cell count ≥ 3 × 109 with neutrophils ≥ 1.5 × 109/L, platelet count ≥ 100 × 109/L and hemoglobin ≥ 6.21 mmol/L (10 g/dL). Total bilirubin ≤ 1.5 × upper limit of reference range and AST and ALT ≤ 2.5 × upper limit of reference range within the last 28 days before inclusion. * Aged 18 or above Exclusion Criteria: * Neuropathic pain origin in the central nervous system. * Phantom limb pain or a significant component of nociceptive pain. * Ascending distal small fiber peripheral neuropathy. * Patients pr…