Effect of Pregabalin in Patients With Radiotherapy-related Neuropathic Pain

Study Overview
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Brief Summary
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Rationale: Pregabalin is effective on radiotherapy-related neuropathic pain. Purpose: This randomized, double-blind, placebo-controlled trial aims to investigate the effect and safety of pregabalin in treating radiotherapy-related neuropathic pain.

Detailed Description
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Radiotherapy for cancer is associated with peripheral neuropathies, especially with brachial plexus neuropathy and trigeminal neuralgia, which included painful sensation that are described as burning, aching, spasm, or tingling. Though there is some recommendation about neuropathic pain, there is no definite drug which is recommended for radiotherapy-related neuropathic pain. Pregabalin, a central nervous system(CNS)-active compound, is an analog of the neurotransmitter gamma-aminobutyric acid. It has been proved an effective treatment for diabetic peripheral neuropathy and postherpetic neuralgia in previous clinical trials. This study plans to evaluate the efficacy of pregabalin versus placebo for relieving radiotherapy-related peripheral neuropathic pain, and assessed its safety.

Official Title
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Effect of Pregabalin in Patients With Radiotherapy-Related Neuropathic Pain: a Randomized, Double-blind, Placebo-controlled Trial

Conditions
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Neuropathic Pain

Intervention / Treatment
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* Drug: Pregabalin
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients must have received radiation therapy for histologically confirmed head and neck cancer. Clinical evidence support the diagnosis of radiation-related neuropathic pain (confirmed by the Michigan Neuropathy Screening Instrument) and had a daily pain score of 4 or higher based on a numerical rating scale (0-10 points). Neuropathic pain defined according to clinical history, symptoms, physical signs, and a score>= 12 in Chinese version of Leeds Assessment of Neuropathic Symptoms and Signs questionnaire by two neurology specialists. The mean duration of pain is more than 4 weeks. Fertile women who are willing to take contraception during the trial. Routine laboratory studies with bilirubin </=2 * upper limits of normal (ULN), aspartate aminotransferase (AST or SGOT) < 2 * ULN, creatinine <1.0 * ULN, red-cell count >/= 4,000 per cubic millimeter; white-cell count >/=1500 per cubic millimeter, platelets >/= 75,000 per cubic millimeter; Hb >/=9.0. Ability to understand and willingness to sign a written informed consent document. Exclusion Criteria: Current diagnosis of tumor recurrence or metastasis and evidence of tumor associated pain. Evidence of secondary neuropathic pain other than radiation. Treatment with carbamazepine, gabapentin or pregabalin within 30 days before study enrollment. Ongoing treatment for neuropathic pain. History of anaphylactic response to pregabalin. Evidence of sever systematic diseases.

Ages Eligible for Study
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Minimum Age: 18 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: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Pregabalin<br>Arm I:At the 4-week dose-titration phase, will receive one capsule of pregabalin (75 mg) twice daily from Day 1 to Day 7, and two capsules of pregabalin (150 mg) twice daily from Day 8 to Day 14. From Day 15 to Day 28, patients will perform dosage adjustments based on the pain relief and tolerability. At maintenance phase, patients will take the optimized dosage of pregabalin. | Drug: Pregabalin<br>* At the 4-week dose-titration phase, will receive one capsule of pregabalin (75 mg) twice daily from Day 1 to Day 7, and two capsules of pregabalin (150 mg) twice daily from Day 8 to Day 14. From Day 15 to Day 28, patients will perform dosage adjustments based on the pain relief and tolerability. At maintenance phase, patients will take the optimized dosage of pregabalin.<br>* Other names: Lyrica;|
| Placebo Comparator: Placebo<br>Arm II:At the 4-week dose-titration phase, will receive one capsule of placebo twice daily from Day 1 to Day 7, and two capsules of placebo twice daily from Day 8 to Day 14. From Day 15 to Day 28, patients will perform dosage adjustments based on the pain relief and tolerability. At maintenance phase, patients will take the optimized dosage of placebo. | Drug: Placebo<br>* At the 4-week dose-titration phase, will receive one capsule of placebo twice daily from Day 1 to Day 7, and two capsules of placebo twice daily from Day 8 to Day 14. From Day 15 to Day 28, patients will perform dosage adjustments based on the pain relief and tolerability. At maintenance phase, patients will take the optimized dosage of placebo.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Numeric Rating Scale (NRS) at week 16 | The primary efficacy measure is the reduction of NRS from baseline to week 16. | week 16 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Brief Pain Inventory (BPI) | The investigators compare the BPI scores at week 16 with those at baseline. | week 16 | 
| the Profile of Mood States-Short Form (POMS-SF) | The investigators compare the POMS-SF scores at week 16 with those at baseline. | week 16 | 
| the World Health Organization Quality of Life-BREF (WHOQOL-BREF) | The investigators compare the WHOQOL-BREF scores at week 16 with those at baseline. | week 16 | 
| Patient Global Impression of Change (PGIC) | Number of Participants With Treatment Success at the End of Therapy as Measured by the Patient Global Impression of Change (PGIC). A treatment success is defined as Much or Very Much Improved at the Week 16. The PGIC is a 7-point Likert Scale, ranging from very much worse to very much improved | week 16 | 
| Clinical Global Impression of Change (CGIC) | Number of Participants With Treatment Success at the End of Therapy Based on Clinical Global Impression of Change (CGIC) . A treatment success is defined as Much or Very Much Improved at the Week 16. The PGIC is a 7-point Likert Scale, ranging from very much worse to very much improve. | week 16 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Radiation, Neuropathic Pain, Pregabalin