The Efficacy and Safety of Pregabalin Combined With Venlafaxine in Patients With Fibromyalgia

Not Applicable

Not yet recruiting

• Conditions: Fibromyalgia; Pregabalin; Venlafaxine; Pain
• Interventions: Drug: Pregabalin; Drug: Pregabalin with venlafaxine

• Registration Number: NCT07186751
• Lead Sponsor: Beijing Tiantan Hospital

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, has demonstrated efficacy in FM by modulating pain pathways through increased serotonin and norepinephrine availability. Several studies have highlighted benefits of venlafaxine in FM. We hypothesize that the combination of pregabalin with venlafaxine may offer greater pain relief compared pregabalin monotherapy, without a significant increase in adverse effects for patients with FM.

Detailed Description

Not available

Study Timeline

• Status Verified: 2025-09
• Study First Submitted: 2025-09-16
• Study First Submitted QC: 2025-09-16
• Last Update Submitted: 2025-09-16
• Study Start: 2025-09-20
• Study First Posted: 2025-09-22
• Last Update Posted: 2025-09-22
• Primary Completion: 2027-06-30
• Study Completion: 2027-08-31

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 384

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, venlafaxine 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.

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Pregabalin monotherapy group	Pregabalin	-
Pregabalin with venlafaxine group	Pregabalin with venlafaxine	-

Primary Outcome Measures

Name	Time	Method
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 Outcome Measures

Name	Time	Method
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.
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 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 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.

Trial Locations

Locations (1)

Beijing Tiantan Hospital, Beijing, Beijing 100070; 🇨🇳 Beijing, China