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INTRODUCTION: The International Neuromodulation Society convened a multispecialty group of physicians and scientists based on expertise with international representation to establish evidence-based guidance on intrathecal drug delivery in treating chronic pain. This Polyanalgesic Consensus Conference (PACC)® project, created more than two decades ago, intends to provide evidence-based guidance for important safety and efficacy issues surrounding intrathecal drug delivery and its impact on the practice of neuromodulation. MATERIALS AND METHODS: Authors were chosen on the basis of their clinical expertise, familiarity with the peer-reviewed literature, research productivity, and contributions to the neuromodulation literature. Section leaders supervised literature searches of MEDLINE, BioMed Central, Current Contents Connect, Embase, International Pharmaceutical Abstracts, Web of Science, Google Scholar, and PubMed from 2017 (when PACC® last published guidelines) to the present. Identified studies were graded using the United States Preventive Services Task Force criteria for evidence and certainty of net benefit. Recommendations are based on the strength of evidence or consensus when evidence is scant. RESULTS: The PACC® examined the published literature and established evidence- and consensus-based recommendations to guide best practices. Additional guidance will occur as new evidence is developed in future iterations of this process. CONCLUSIONS: The PACC® recommends best practices regarding intrathecal drug delivery to improve safety and efficacy. The evidence- and consensus-based recommendations should be used as a guide to assist decision-making when clinically appropriate.
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BACKGROUND AND OBJECTIVES: The Patient Registry of Intrathecal Ziconotide Management evaluated the long-term effectiveness and safety of intrathecal ziconotide. METHODS: The study was a prospective, multicenter observational study of intrathecal ziconotide in US clinical practice. Patients were adults with severe chronic pain that warranted intrathecal therapy. Ziconotide was initiated as the single agent in the pump; however, other intrathecal medications were permitted. The primary efficacy outcome was ≥30% reduction in numeric pain rating scale score from baseline at week 12. A secondary outcome was patient global impression of change. Adverse events were solicited at each visit. RESULTS: The registry enrolled 93 patients. Seventy-four and 28 patients completed 12 weeks and 18 months of treatment, respectively. In the overall patient population, 17.4% had ≥30% pain reduction from baseline at week 12, with a mean reduction in pain of 10.9%. At month 18, 38.5% of patients had ≥30% pain reduction from baseline, with a mean pain reduction of 24.7%. Patient-rated improvement was reported in 67% of patients at week 12 and 71% at month 18. Almost all patients experienced adverse events, the most common of which were nausea (25.8%), confusional state (22.6%), and dizziness (20.4%). CONCLUSIONS: Final study analyses showed that intrathecal ziconotide provided clinically meaningful pain relief in 17.4% and 38.5% of patients at week 12 and month 18, respectively. At these same time points, patient-rated improvement was reported in at least two-thirds of patients. The safety profile was consistent with that listed in the ziconotide prescribing information.
Subject(s)
Analgesics, Non-Narcotic , omega-Conotoxins , Adult , Analgesics, Non-Narcotic/adverse effects , Humans , Injections, Spinal , Pain Measurement , Prospective Studies , Registries , omega-Conotoxins/adverse effectsABSTRACT
OBJECTIVES: To evaluate the evidence for morphine and ziconotide as firstline intrathecal (IT) analgesia agents for patients with chronic pain. METHODS: Medline was searched (through July 2017) for "ziconotide" or "morphine" AND "intrathecal" AND "chronic pain," with results limited to studies in human populations. RESULTS: The literature supports the use of morphine (based primarily on noncontrolled, prospective, and retrospective studies) and ziconotide (based on randomized controlled trials and prospective observational studies) as first-choice IT therapies. The 2016 Polyanalgesic Consensus Conference (PACC) guidelines recommended both morphine and ziconotide as firstline IT monotherapy for localized and diffuse chronic pain of cancer-related and non-cancer-related etiologies; however, one consensus point emphasized ziconotide use, unless contraindicated, as firstline IT therapy in patients with chronic non-cancer-related pain. Initial IT therapy choice should take into consideration individual patient characteristics (e.g., pain location, response to previous therapies, comorbid medical conditions, psychiatric history). Trialing is recommended to assess medication efficacy and tolerability. For both morphine and ziconotide, the PACC guidelines recommend conservative initial dosing strategies. Due to its narrow therapeutic window, ziconotide requires careful dose titration. Ziconotide is contraindicated in patients with a history of psychosis. IT morphine administration may be associated with serious side effects (e.g., respiratory depression, catheter tip granuloma), require dose increases, and cause dependence over time. CONCLUSION: Based on the available evidence, morphine and ziconotide are recommended as firstline IT monotherapy for cancer-related and non-cancer-related pain. The choice of first-in-pump therapy should take into consideration patient characteristics and the advantages and disadvantages of each medication.
Subject(s)
Analgesics, Non-Narcotic/administration & dosage , Analgesics, Opioid/administration & dosage , Chronic Pain/drug therapy , Morphine/administration & dosage , Pain Management/methods , omega-Conotoxins/administration & dosage , Humans , Injections, SpinalABSTRACT
BACKGROUND: The Patient Registry of Intrathecal Ziconotide Management (PRIZM) evaluated long-term effectiveness, safety, and tolerability of intrathecal ziconotide treatment in clinical practice. METHODS: Patient Registry of Intrathecal Ziconotide Management was an open-label, long-term, multicenter, observational study of adult patients with severe chronic pain. This interim analysis (data through July 10, 2015) of ziconotide as the first vs. not first intrathecal agent in pump included change from baseline in the Numeric Pain Rating Scale (NPRS; primary efficacy measure) and Patient Global Impression of Change (PGIC) scores. RESULTS: Enrollment closed at 93 patients; data collection was ongoing at the time of this interim analysis. Fifty-one patients (54.8%) received ziconotide as the first agent in pump (FIP+), whereas 42 (45.2%) did not (FIP-). Mean (SD) baseline NPRS scores were 7.4 (1.9) and 7.9 (1.6) in FIP+ and FIP- patients, respectively. Mean (SEM) percentage changes in NPRS scores were -29.4% (5.5%) in FIP+ patients (n = 26) and +6.4% (7.7%) in FIP- patients (n = 17) at month 6 and -34.4% (9.1%) in FIP+ patients (n = 14) and -3.4% (10.2%) in FIP- patients (n = 9) at month 12. Improvement from baseline, measured by PGIC score, was reported in 69.2% of FIP+ (n = 26) and 35.7% of FIP- (n = 14) patients at month 6 and 85.7% of FIP+ (n = 7) and 71.4% of FIP- (n = 7) patients at month 12. The most common adverse events (≥ 10% of patients overall as of the data cut) were nausea (19.6% vs. 7.1% of FIP+ vs. FIP- patients, respectively), confusional state (9.8% vs. 11.9%), and dizziness (13.7% vs. 7.1%). CONCLUSIONS: Greater improvements in efficacy outcomes were observed when ziconotide was initiated as first-line intrathecal therapy vs. not first intrathecal agent in pump. The adverse event profile was consistent with the ziconotide prescribing information.
Subject(s)
Analgesics, Non-Narcotic/administration & dosage , Chronic Pain/drug therapy , Pain Management/methods , omega-Conotoxins/administration & dosage , Adult , Aged , Female , Humans , Infusion Pumps, Implantable , Injections, Spinal , Longitudinal Studies , Male , Middle Aged , Pain MeasurementABSTRACT
INTRODUCTION: Ziconotide is a non-opioid analgesic for intrathecal (IT) administration. The aim of this review is to provide a comprehensive and clinically relevant summary of the literature on dosing and administration with IT ziconotide in the management of refractory chronic pain, and to describe novel dosing strategies intended to improve clinical outcomes. MATERIALS AND METHODS: A Medline search was conducted for "ziconotide," supplemented by manual searching of published bibliographies and abstracts from conferences. RESULTS: Early experience with IT ziconotide in clinical trials combined with improved understanding of drug pharmacokinetics in the cerebrospinal fluid have led to a reappraisal of approaches to trialing and initiation of continuous-infusion therapy in an effort to improve tolerability. The traditional paradigm of trialing by inpatient continuous infusion may be shifting toward outpatient trialing by IT bolus, although definitions of success and specific protocols remain to be agreed upon. Expert consensus on IT continuous infusion with ziconotide suggests a starting dose of 0.5 to 1.2 mcg/day followed by dose titration of ≤0.5 mcg/day on a no more than weekly basis, according to individual patients' pain reductions and regimen tolerability. DISCUSSION: Newer modalities that include patient-controlled analgesia and nocturnal flex dosing have been shown to hold promise of further improvements in ziconotide efficacy and tolerability. CONCLUSIONS: Clinical trials and experience confirm the feasibility and usefulness of IT ziconotide in the management of refractory chronic pain. Emerging evidence suggests that additional IT delivery options may further expand the usefulness and benefits of ziconotide.
Subject(s)
Analgesics, Non-Narcotic/administration & dosage , Chronic Pain/drug therapy , Infusions, Spinal/methods , Pain, Intractable/drug therapy , omega-Conotoxins/administration & dosage , Databases, Bibliographic/statistics & numerical data , Dose-Response Relationship, Drug , Humans , Treatment OutcomeABSTRACT
Some patients with chronic pain who are intolerant of or refractory to treatment with systemic analgesics may benefit from intrathecal therapy. Ziconotide is the first nonopioid analgesic approved by the United States Food and Drug Administration for intrathecal administration. Several randomized, double-blind, placebo-controlled clinical trials have demonstrated the efficacy and safety of ziconotide. However, the maximum recommended dosing and titration schedule provided in the prescribing information may be too aggressive for some patients, and experience has demonstrated that ziconotide is better tolerated with slower titration to a lower maximum dose. Efficacy can be assessed by an evaluation of changes in pain, functionality, and quality of life. Cognitive adverse events may be subtle; therefore, it is important that health care professionals not only monitor patients for signs and symptoms of cognitive adverse events, but also teach family members how to do the same. Careful patient assessment and monitoring can help optimize the potential benefit from treatment with ziconotide.
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Analgesics, Non-Narcotic/administration & dosage , Chronic Pain/drug therapy , Drug Monitoring/methods , Pain Management/methods , omega-Conotoxins/administration & dosage , Humans , Injections, SpinalABSTRACT
INTRODUCTION: Continuous intrathecal infusion of drugs to treat chronic pain and spasticity has become a standard part of the algorithm of care. The use of opioids has been associated with noninfectious inflammatory masses at the tip of the intrathecal catheter, which can result in neurologic complications. METHODS: The Polyanalgesic Consensus Conference is a meeting of a group of well-published and experienced practitioners; the purpose of the meeting is to update the standard of care for intrathecal therapies to reflect current knowledge gleaned from literature and clinical experience. An exhaustive literature search was performed, and information from this search was provided to panel members. Analysis of the published literature was coupled with the clinical experience of panel participants to form recommendations regarding intrathecal inflammatory masses or granulomas. RESULTS: The panel has made recommendations for the prevention, diagnosis, and management of intrathecal granulomas. CONCLUSION: The use of chronic infusions of intrathecal opioids is associated with the formation of inflammatory masses at the intrathecal catheter tip in a small minority of treated patients. Nonetheless, the appearance of these space-occupying lesions can lead to devastating neurologic sequelae. The prevention, early detection, and successful treatment of intraspinal granulomas are important considerations when offering intrathecal drug therapy to patients with chronic intractable pain.
Subject(s)
Catheters/adverse effects , Granuloma/etiology , Infusion Pumps, Implantable/adverse effects , Injections, Spinal/adverse effects , Analgesics, Opioid/administration & dosage , Analgesics, Opioid/adverse effects , Granuloma/prevention & control , Humans , Inflammation/etiology , Infusion Pumps, Implantable/standards , Injections, Spinal/methods , Injections, Spinal/standardsABSTRACT
INTRODUCTION: Targeted intrathecal drug infusion to treat moderate to severe chronic pain has become a standard part of treatment algorithms when more conservative options fail. This therapy is well established in the literature, has shown efficacy, and is an important tool for the treatment of both cancer and noncancer pain; however, it has become clear in recent years that intrathecal drug delivery is associated with risks for serious morbidity and mortality. METHODS: The Polyanalgesic Consensus Conference is a meeting of experienced implanting physicians who strive to improve care in those receiving implantable devices. Employing data generated through an extensive literature search combined with clinical experience, this work group formulated recommendations regarding awareness, education, and mitigation of the morbidity and mortality associated with intrathecal therapy to establish best practices for targeted intrathecal drug delivery systems. RESULTS: Best practices for improved patient care and outcomes with targeted intrathecal infusion are recommended to minimize the risk of morbidity and mortality. Areas of focus include respiratory depression, infection, granuloma, device-related complications, endocrinopathies, and human error. Specific guidance is given with each of these issues and the general use of the therapy. CONCLUSIONS: Targeted intrathecal drug delivery systems are associated with risks for morbidity and mortality that can be devastating. The panel has given guidance to treating physicians and healthcare providers to reduce the incidence of these problems and to improve outcomes when problems occur.
Subject(s)
Analgesics/administration & dosage , Chronic Pain/drug therapy , Drug Delivery Systems/standards , Infusion Pumps, Implantable/standards , Injections, Spinal/standards , Chronic Pain/mortality , Drug Delivery Systems/methods , Humans , Injections, Spinal/methodsABSTRACT
INTRODUCTION: The use of intrathecal (IT) infusion of analgesic medications to treat patients with chronic refractory pain has increased since its inception in the 1980s, and the need for clinical research in IT therapy is ongoing. The Polyanalgesic Consensus Conference (PACC) panel of experts convened in 2000, 2003, and 2007 to make recommendations on the rational use of IT analgesics based on preclinical and clinical literature and clinical experiences. METHODS: The PACC panel convened again in 2011 to update the standard of care for IT therapies to reflect current knowledge gleaned from literature and clinical experience. A thorough literature search was performed, and information from this search was provided to panel members. Analysis of published literature was coupled with the clinical experience of panel members to form recommendations regarding the use of IT analgesics to treat chronic pain. RESULTS: After a review of literature published from 2007 to 2011 and discussions of clinical experience, the panel created updated algorithms for the rational use of IT medications for the treatment of neuropathic pain and nociceptive pain. CONCLUSIONS: The advent of new algorithmic tracks for neuropathic and nociceptive pain is an important step in improving patient care. The panel encourages continued research and development, including the development of new drugs, devices, and safety recommendations to improve the care of patients with chronic pain.
Subject(s)
Algorithms , Analgesics/administration & dosage , Drug Delivery Systems/standards , Injections, Spinal/standards , Pain/drug therapy , Drug Delivery Systems/methods , Humans , Injections, Spinal/methodsABSTRACT
OBJECTIVES: The majority of patients seeking medical care for chronic pain consult a primary care physician (PCP). Because systemic opioids are commonly prescribed to patients with chronic pain, PCPs are attempting to balance the competing priorities of providing adequate pain relief while reducing risks for opioid misuse and overdose. It is important for PCPs to be aware of pain management strategies other than systemic opioid dose escalation when patients with chronic pain fail to respond to conservative therapies and to initiate a multimodal treatment plan. METHODS: The Medline database and evidence-based treatment guidelines were searched to identify publications on intrathecal (IT) therapy for the management of chronic pain. Selection of publications relevant to PCPs was based on the authors' clinical and research expertise. RESULTS: IT administration delivers analgesic medication directly into the cerebrospinal fluid, avoiding first-pass effect and bypassing the blood-brain barrier, thereby requiring lower medication doses. Morphine, a µ-opioid receptor agonist, and ziconotide, a non-opioid, selective N-type calcium channel blocker, are the only analgesics approved by the US Food and Drug Administration to treat chronic refractory pain by the IT route. Patients who are potential candidates for IT therapy may benefit from evaluation by an interventional pain physician. PCPs can play an important role in patient selection and referral for IT therapy and provide ongoing collaborative care for patients receiving IT therapy, including monitoring for efficacy and adverse events and facilitating communication with the treating specialist. CONCLUSIONS: Collaboration between PCPs and pain specialists may improve outcomes of and patient satisfaction with IT therapy and other interventional treatments.