Intrathecal Bolus Doses of Ziconotide

The intrathecal route for administration of analgesia has been in use in clinical practice for the last 3 decades. It is recommended to trial the patient with intrathecal drug therapy prior to implanting an intrathecal drug delivery device. Trials can be performed using a single bolus injection or by a continuous intrathecal infusion administered through an external catheter. Ziconotide has been approved by EMA for the treatment of chronic severe pain in 2005. So far trials of ziconotide have largely been conducted using external catheters with the drug administered by intrathecal infusion over a number of weeks. Infusions trials have been shown to be expensive, associated with a risk of meningitis and inconvenient to both patient and physician. The option of conducting a trial of intrathecal ziconotide therapy by bolus injection remains unexplored. This study aims to evaluate the efficacy and safety of a bolus dose of ziconotide (Prialt®) to evaluate the option of continuous administration of the drug via implanted pump in the event of a successful trial.