title: Ziconotide Combination Intrathecal Therapy for Noncancer Pain Is Limited Secondary to Delayed Adverse Effects: A Case Series With a 24-Month Follow-Up.
abstract: OBJECTIVE
  The efficacy and safety of ziconotide as a single agent has been evaluated in few short-term clinical trials and open-label studies. Ziconotide use is challenging given its adverse effect (AE) profile. The objective of this study is to describe the long-term efficacy and AEs of ziconotide used as an adjunct to other intrathecal (IT) agents in chronic noncancer pain patients.
  
  
  METHODS
  A case series of chronic noncancer pain patients who had suboptimal pain control from IT therapy. Ziconotide was introduced in the IT infusion mixture after a successful ziconotide trial. Pain scores, IT doses, as well as AEs were recorded and analyzed from trial to initial ziconotide infusion and up to 24 months.
  
  
  RESULTS
  Fifteen patients underwent ziconotide trials. Four subjects failed the trial, and 11 proceeded to continuous ziconotide treatment. Seven out of 11 patients experienced AEs resulting in ziconotide discontinuation. Two of the seven subjects who required discontinuation of ziconotide had improved pain. Four subjects were able to continue IT ziconotide through 24 months.
  
  
  CONCLUSIONS
  A high incidence of AEs limits the usefulness of IT ziconotide as adjunct therapy. Our results are limited by the size of our patient population; however, they represent a long follow-up period, which is limited in most current publications on this IT peptide. While ziconotide is a needed IT agent, more studies are necessary to better understand the factors that would improve the treatment to trial ratio as well as the long-term efficacy of IT ziconotide treatment.
authors: Department of Anesthesiology, Division of Pain Medicine, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, OH, USA.
authors: Salim M
authors: SM
authors: Hayek
authors: Department of Anesthesiology, Division of Pain Medicine, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, OH, USA.
authors: Michael C
authors: MC
authors: Hanes
authors: Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Boston, MA, USA.
authors: Connie
authors: C
authors: Wang
authors: Department of Anesthesiology, Division of Pain Medicine, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, OH, USA.|Pain Medicine & Spine Care, Louis Stokes Veterans Administration Medical Center, Cleveland, OH, USA.
authors: I Elias
authors: IE
authors: Veizi
mesh_terms: D018712:Analgesics, Non-Narcotic / Q000009:adverse effects*; D015331:Cohort Studies; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D007278:Injections, Spinal / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000188:drug therapy*; D059408:Pain Management; D010147:Pain Measurement; D020960:omega-Conotoxins / Q000009:adverse effects* / Q000627:therapeutic use
chemical_list: D018712:Analgesics, Non-Narcotic; D020960:omega-Conotoxins; C078452:ziconotide
keywords: Adverse effects; intrathecal drug delivery; nonmalignant pain; ziconotide