Pretreatment Identification of Duloxetine Success in Neuropathic Pain Patients

Pretreatment Identification of Duloxetine Success in Neuropathic Pain Patients Based on Assessment of Endogenous Analgesia Capabilities

The purpose of this study is to identify, prior to prescribing, which neuropathic pain patients will benefit from duloxetine more specific the investigators aims are to:

• Verify whether presence of chronic pain alters the pain modulation mechanisms, such as DNIC (diffuse noxious inhibitory control) and TS (temporal summation).
• Investigate whether anti-neuropathic medications such as duloxetine indeed change the pain modulation profile, and whether this profile change is associated with a reduction of clinical pain.

Study Overview

• Status: Completed
• Conditions: Diabetes; Painful Neuropathy
• Intervention / Treatment: Drug: Duloxetine

Detailed Description

There is no accepted practice for selecting among recommended medications for the individual neuropathic pain patient. Guidelines published to date provided the evidence for their efficacy, however, data is not available on how to choose the right medication for the right patient in order to avoid long 'trial and error's. We hypothesize that medications affecting specific process of pain modulation will be more efficacious in patients expressing dysfunction of that specific process. Therefore, medications that enhance descending inhibition such as SSNRI will be more efficacious in patients with less-efficient pain inhibition. The latter is assessed by the conditioned pain modulation (CPM) paradigm. Accordingly, the aim of this study is to examine this hypothesis in painful diabetic neuropathy patients, using duloxetine, an SSNRI agent assumed to augment descending pain inhibition by reuptake inhibition of noradrenalin and serotonin in the spinal cord dorsal horn synapses. We expect to find better effect of duloxetine in those patients whose pain inhibition capability is less efficient, as expressed by their baseline CPM. Further, we aim to evaluate whether pro-nocieptive pattern of pain modulation indeed reverses in response to treatment. This will be explored by comparing the CPM responses before and after treatment, and by correlating pain alleviation with the possible changes in CPM.

• Study Type: Interventional
• Enrollment (Actual): 51
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Israel
  • Haifa, Israel
    • Rambam Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 85 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Patients diagnosed as having painful diabetic neuropathy.
• Pain is experienced for more than 3 months.
• Pain severity is ≥ 4 on a 0-10 scale (last month average).

Exclusion Criteria:

• Patient already receiving duloxetine or another SNRI/SSRI.
• Known hypersensitivity to duloxetine or any of the inactive ingredients.
• Treatment with a monoamine oxidase inhibitor (MAOI) within 14 days of randomization or potential need to use an MAOI during the study or within 5 days of discontinuation of study drug.
• Uncontrolled narrow-angle glaucoma
• Because of the risk of serious ventricular arrhythmias and sudden death potentially associated with elevated plasma levels of thioridazine (Mellaril), Cymbalta and thioridazine should not be co-administered
• Inability to perform psychophysical testing, due to language or perceptual barriers.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Duloxetine; The first week of the treatment is the placebo treatment. The effect of placebo will be taken into consideration for further evaluation the duloxetine effect on clinical pain and descending pain inhibition capabilities.	Drug: Duloxetine; First week of placebo. then, initial dose of 30 mg/d will be given for one week, in order to minimize possible side effects and drop outs, and then a fixed dose of 60 mg/d will be given for additional 4 weeks; Other Names: SSNRI

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Prediction of duloxetine pain relief efficacy by pre-treatment extent of the CPM response	Regression model will assess predictive value of baseline pre-treatment extent of the CPM response and pain relief efficacy of duloxetine treatment.	2 year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Treatment-related increase in CPM response	We propose that treatment-related increase in CPM response will be correlated with duloxetine pain relief efficacy	2 years

Collaborators and Investigators

• Sponsor: Rambam Health Care Campus
• Collaborators: Eli Lilly and Company
• Investigators: Principal Investigator: David Yarnitsky, PhD, Rambam Health Care Campus

Publications and helpful links

General Publications

• Yarnitsky D, Granot M, Nahman-Averbuch H, Khamaisi M, Granovsky Y. Conditioned pain modulation predicts duloxetine efficacy in painful diabetic neuropathy. Pain. 2012 Jun;153(6):1193-1198. doi: 10.1016/j.pain.2012.02.021. Epub 2012 Apr 3.

Study record dates

Study Major Dates

• Study Start (Actual): June 1, 2010
• Primary Completion (Actual): August 1, 2012
• Study Completion (Actual): August 1, 2012

Study Registration Dates

• First Submitted: May 17, 2011
• First Submitted That Met QC Criteria: May 29, 2011
• First Posted (Estimate): June 1, 2011

Study Record Updates

• Last Update Posted (Actual): October 11, 2017
• Last Update Submitted That Met QC Criteria: October 10, 2017
• Last Verified: October 1, 2017

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Nervous System Diseases; Pain; Neurologic Manifestations; Neuromuscular Diseases; Peripheral Nervous System Diseases; Neuralgia; Physiological Effects of Drugs; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Peripheral Nervous System Agents; Analgesics; Sensory System Agents; Psychotropic Drugs; Neurotransmitter Uptake Inhibitors; Membrane Transport Modulators; Antidepressive Agents; Dopamine Agents; Serotonin and Noradrenaline Reuptake Inhibitors; Duloxetine Hydrochloride
• Other Study ID Numbers: diabetic_Duloxetine09CTIL