A Phase 4, Randomized, Double-blind, Placebo-controlled, Cross-over Clinical Trial of a Single Shot of Intrathecal Ziconotide for the Treatment of Chronic, Medically Refractory Pain From Painful Peripheral Neuropathy or Myelopathy

Study Hypothesis: We intend to determine if a single shot trial (SST) of intrathecal (IT) ziconotide will temporarily reduce pain in these patients. In the proposed study, patients will receive two injections, one of which is the ziconotide and one which is a placebo. They will be blinded and not know which order they receive the treatment versus placebo. The results of this clinical trial will provide a focused examination of ziconotide efficacy and safety in patients with painful neuropathies or myelopathies that have not been effectively treated with other pain medications. Moreover, the use of a single shot trial (SST) IT injection in the outpatient setting will provide evidence for application of this technique in outpatient neurological clinical practice, thereby improving access to this specific patient population. Ziconotide is currently FDA approved for this indication and route of administration. Therefore, a study design that improves the feasibility of ziconotide trialing specifically in the neurology clinic (that is, single shot administration) is being used in order to ensure its broader use by neurologists who routinely care for neuropathy and myelopathy patients. Information from this study will also inform future studies of predictors for long term efficacy after pump placement.