Fibromyalgia, Pain, Pregabalin
Conditions
Brief summary
Fibromyalgia (FM) is a chronic pain syndrome characterized by widespread pain, fatigue, and emotional disorders. Its onset is related to factors such as central sensitization and imbalance of neurotransmitters. The current mainstream treatments include pregabalin, but the efficacy of pregabalin is limited, with only 25%-40% pain relief rate, and adverse reactions are common. Selective serotonin and norepinephrine reuptake inhibitors (SNRIs), such as duloxetine and venlafaxine, have demonstrated efficacy in FM by modulating pain pathways through increased serotonin and norepinephrine availability. Desvenlafaxine, the third SNRI, was found with lower adverse effects compared with duloxetine and venlafaxine. We hypothesize that the combination of pregabalin with desvenlafaxine may offer greater pain relief compared pregabalin monotherapy, without a significant increase in adverse effects for patients with FM.
Interventions
DRUGPregabalin
In the pregabalin monotherapy group, pregabalin will be initiated at 150 mg daily, divided into 2 or 3 doses per day, and increased to 300 mg per day after 3 to 7 days, subsequent increases of 150 mg daily may occur every 3 to 7 days, based on individual patient response and tolerability, with a maximum dose of 600 mg daily.
DRUGPregabalin with desvenlafaxine
In the pregabalin with desvenlafaxine group, the dose titration of pregabalin is identical with pregabalin monotherapy group. Desvenlafaxine will be administered at 50 mg daily with breakfast initially. If the initial dose is well-tolerated, the dose could be further escalated by 50 mg per day after 3 days, up to a maximum of 400 mg per day after 7 days. With each dose increase, AEs will be assessed and categorized as mild, moderate, or severe. If participants tolerate the current dose for 2 to 3 days, it will be maintained, with the expectation that tolerance to AEs will develop. If AEs become intolerable, the dose will be decreased back to the previous dose, which was defined as the maximum tolerated dose. In the combination group, dose titration of both pregabalin and desvenlafaxine will be conducted simultaneously. If AEs occur, the next dose regimen should be determined in consultation with a clinical physician.
Sponsors
Jiujiang University Affiliated Hospital
Beijing Tiantan Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Diagnosed with FM according to the 2016 Revisions to the 2010/2011 FM diagnostic criteria; * Aged 18 years or older; * Experiencing moderate to severe FM that have not been effectively alleviated by non-pharmacological treatments and has not received currently recommended pharmacological treatment for FM; * Numeric rating scale (NRS) score ≥ 4 at baseline; * Aspartate aminotransferase and alanine aminotransferase levels less than twice the upper limit of normal; * Estimated glomerular filtration rate of 30 mL/min per 1.73 m2 or higher; * Willing to sign the informed consent form and possessing sufficient cognitive and language abilities to comply with all the study requirements.
Exclusion criteria
* History of hypersensitivity to pregabalin, desvenlafaxine or any of its excipients; * History of epilepsy, or depression requiring antidepressant medications; * Pregnancy or breastfeeding; * Presence of serious systemic diseases, including uncontrolled hypertension, uncontrolled diabetes, or significant cardiac dysfunction; * With acute or chronic pain conditions other than FM.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| The average pain intensity | at the 4-weeks | The average pain intensity over the past 24 hours, rated each morning upon awakening and averaged over 7 days at the 4 weeks. This will be measured based on NRS, where 0 represents no pain and 10 represents worst pain imaginable. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| The proportion of patients achieving pain reduction | At the weeks 1, 2, 4, and 8 | The proportion of patients achieving a ≥ 50% and ≥ 30% reduction in mean baseline pain intensity. The pain intensity will be measured based on NRS, where 0 represents no pain and 10 represents worst pain imaginable. |
| The Revised FM Impact Questionnaire | At the weeks 1, 2, 4, and 8 | The Revised FM Impact Questionnaire assesses the severity of FM symptoms and their impact on daily functioning. It evaluates three linked domains: function, overall impact, and symptoms, using a 0 to10 NRS. The total score ranges from 0 to 100, with higher scores indicating greater disease burden. |
| The Brief Pain Inventory (BPI) severity (BPI-S) and interfere (BPI-I) subscales | At the weeks 1, 2, 4, and 8 | BPI-S accesses pain intensity over the past 24 hours, calculated as the average of items 3 to 6 on the BPI, scored using a 0 to 10 NRS. In the NRS scale, 0 indicates no pain, while 10 represents the worst pain imaginable. The total score ranges from 0 to 40, with higher scores indicating greater pain severity. BPI-I evaluates the degree to which pain interferes with daily activities, including general activity, mood, mobility work, relationships, sleep, and pleasure. This subscale comprises 7 items, each scored from 0 (no interference) to 10 (complete interference), with a total score ranging from 0 to 70. |
| The worst pain intensity | At the weeks 1, 2, 4, and 8 | The worst pain intensity over the past 24 hours, rated each morning upon awakening and averaged over 7 days. The pain intensity will be measured based on NRS, where 0 represents no pain and 10 represents worst pain imaginable. |
| The Medical Outcomes Study Sleep Scale (MOS) | At the weeks 1, 2, 4, and 8 | The MOS is a questionnaire comprising 12 items that assess various aspects of sleep using a 6-point ordinal scale (1 indicating permanence and 6 indicating absence). |
| The Beck Depression Inventory-Ⅱ (BD-Ⅱ) | At the weeks 1, 2, 4, and 8 | The BD-Ⅱ evaluates the severity of depressive symptoms using a 4-point scale from 0 to 3, where 0 indicates no symptom and 3 indicates severe symptomatology. It comprises 21 items, the total score ranging from 0 to 63. |
| Adverse Events | Through study completion, an average of 8 weeks | The incidence and proportion of adverse events will be recorded and categorized as mild, moderate, severe, or life-threatening. AEs are defined as events that arise during treatment, were absent before treatment, or worsen relative to the pretreatment state. |
| The short-form 36 Health Survey (SF-36) | At the weeks 1, 2, 4, and 8 | The SF-36 assesses health-related quality of life, capturing preferences across various health states. It assesses 8 dimensions: physical functioning, physical role limitations due to physical health, bodily pain, general health, vitality, social functioning, emotional role limitations due to emotional problems, and mental health. Scores range from 0 to 100 for each dimension, with higher scores indicating better health status. |
Countries
China
Contacts
Primary ContactFang Luo, M.D.
Outcome results
None listed