Efficacy and Safety of GRT6005 in Patients With Chronic Low Back Pain.

Study Overview
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Brief Summary
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The purpose of this trial is to evaluate the safety and efficacy of once daily orally administered GRT6005 in a total of 3 fixed doses compared to placebo in subjects with moderate to severe chronic Low Back Pain (LBP). The study includes a maximum of 21 days screening period followed by a 2-week titration period and 12-week maintenance double-blind treatment period and a 10-14 day safety follow up period. Patients who are eligible for the double-blind treatment period will be randomized to one of the following treatment groups: GRT6005 low-dose, GRT6005 medium dose, GRT6005 high-dose, Tapentadol or placebo.

Official Title
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Efficacy, Safety, and Tolerability of GRT6005 in Subjects With Moderate to Severe Chronic Low Back Pain.

Conditions
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Low Back Pain

Intervention / Treatment
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* Drug: Matching Placebo
* Drug: Low Dose GRT6005
* Drug: Medium Dose GRT6005
* Drug: High Dose GRT6005
* Drug: Tapentadol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Chronic Low Back Pain of non-malignant origin and present for at least 3 months. Signed informed consent. Pain intensity score of 5 or greater on the 11-point numeric rating scale (where 0 indicates no pain and 10 indicates as bad as you can imagine). On stable analgesic medications (non-opioid and/or opioid medications) for chronic low back pain with regular intake for at least 3 months and dissatisfied with current analgesic treatment. Exclusion Criteria: Female subjects who are pregnant or are breastfeeding. Presence of risk factors for Torsade de Pointes. Any clinically significant disease or laboratory findings that may affect efficacy or safety assessments or may compromise the safety during trial participation, e.g., significant unstable cardiac, vascular, pulmonary, gastrointestinal, endocrine, metabolic, neurological, or psychiatric disorders. History of acute hepatitis within the past 3 months or chronic hepatitis or a positive result on anti-hepatitis A antibody, hepatitis B surface antigen, or anti-hepatitis C antibody. History of human immunodeficiency virus (HIV) infection. History of seizure disorder. Chronic low back pain potentially associated with a specific spinal cause. Surgery or painful procedure during or within 3 months of enrollment. Conditions that contribute and confound the assessment of pain. Subjects with impaired renal function. Subjects with impaired hepatic functionality. Neuromodulation. Cancer. Clinically relevant history of hypersensitivity, allergy or contraindications to any of the Investigational Medicinal Products' excipients, paracetamol/acetaminophen, tapentadol Hydrochloride, or opioid analgesics (or excipients).

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Matching Placebo<br>Twice daily oral administration of matching placebo for 14 weeks | Drug: Matching Placebo<br> <br> |
| Experimental: Low Dose GRT6005<br>Once daily GRT6005 low dose oral administration for 12 weeks with a titration period of 2 weeks. | Drug: Low Dose GRT6005<br> <br> |
| Experimental: Medium Dose GRT6005<br>Once daily GRT6005 medium dose oral administration for 12 weeks with a titration period of 2 weeks. | Drug: Medium Dose GRT6005<br> <br> |
| Experimental: High Dose GRT6005<br>Once daily GRT6005 high dose oral administration for 12 weeks with a titration period of 2 weeks. | Drug: High Dose GRT6005<br> <br> |
| Active Comparator: Tapentadol<br>Twice daily oral administration of Tapentadol for 12 weeks with a titration period of 2 weeks. | Drug: Tapentadol<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| European Union: the change from baseline pain to the weekly average 24-hour pain during the entire 12 weeks of the maintenance phase of the double-blind Treatment Period. |  | Baseline to End of Treatment (Week 14) | 
| United States: the change from baseline pain to the average 24-hour pain during Week 12 of the maintenance phase. |  | Baseline to End of Treatment (Week 14) |