Chronic Pelvic Pain, Chronic Pelvic Pain Syndrome
Conditions
Keywords
chronic pain, pregabalin, chronic pelvic pain
Brief summary
This multicenter, randomized, prospective, open-label, controlled trial will evaluate the efficacy and safety of oral pregabalin as an adjunct to standard conservative treatment in women with chronic pelvic pain (CPP). Approximately 308 women aged 18 to 65 years with moderate to severe CPP lasting more than 6 months will be enrolled and randomly assigned in a 1:1 ratio to either standard conservative treatment alone or standard conservative treatment plus oral pregabalin. Standard conservative treatment will follow a biopsychosocial management approach and may include patient education, body awareness therapy, cognitive interventions, and individualized conservative care. Participants assigned to the pregabalin group will receive oral pregabalin beginning at 150 mg/day in two divided doses. The dose may be gradually increased according to pain relief and tolerability, up to a maximum of 600 mg/day, and maintained for 12 weeks. The primary outcome is the change in mean pain intensity from baseline to Week 12, measured using a visual analogue scale (VAS), with scores ranging from 0 (no pain) to 10 (worst pain imaginable). Secondary outcomes include pain intensity at Weeks 2, 4, 8, and 12; pregabalin dosage; overall treatment satisfaction; health-related quality of life assessed using the Short Form-12 questionnaire; gynecologic pain assessed using the McCormack scale; and adverse events throughout the study. The total follow-up period is 12 weeks, with assessments conducted at Weeks 2, 4, 8, and 12. Because of the open-label design, participants and treating physicians will know the treatment assignment. Outcome assessors and statisticians will be blinded to treatment allocation. The study will determine whether adding pregabalin to standard conservative treatment improves pain and related patient-reported outcomes while maintaining an acceptable safety profile in women with CPP.
Detailed description
Chronic pelvic pain (CPP) in women is a persistent and multifactorial condition that can substantially affect physical functioning, emotional well-being, sexual health, and quality of life. Pain may arise from multiple overlapping pelvic, urinary, gynecologic, musculoskeletal, and psychosocial factors. Central sensitization, characterized by increased responsiveness of the nervous system to painful and nonpainful stimuli, is considered an important contributor to persistent pain in some patients. Consequently, symptom control often requires an individualized, multimodal approach. Conservative management, including education, physical and behavioral therapies, and other biopsychosocial interventions, is recommended for women with CPP. However, the response is variable, and some patients continue to experience clinically important pain despite these measures. Common pharmacologic options have limitations: evidence for long-term benefit from nonsteroidal anti-inflammatory drugs is limited, hormonal treatments are applicable only to selected pain conditions, and prolonged opioid therapy is generally discouraged because of safety concerns. Evidence for gabapentinoids in women with CPP is also inconsistent, creating a need to evaluate alternative treatment strategies. Pregabalin binds to the alpha-2-delta subunit of voltage-gated calcium channels and reduces the release of excitatory neurotransmitters involved in abnormal pain processing. Compared with gabapentin, pregabalin has more predictable absorption and dose-related pharmacokinetics, which may facilitate individualized dose adjustment. Although pregabalin has been studied in other chronic pain conditions and in men with chronic prostatitis/chronic pelvic pain syndrome, high-quality evidence in women with CPP remains limited. This study is designed to determine whether adding pregabalin to standard conservative care provides clinically meaningful symptom relief for women with moderate to severe CPP. The flexible dose-adjustment approach is intended to reflect clinical practice by balancing analgesic response and tolerability. In addition to pain, the study will examine patient satisfaction, health-related quality of life, gynecologic pain-related symptoms, treatment adherence, and adverse events. The findings may clarify the role of pregabalin as an adjunctive option for women whose symptoms remain insufficiently controlled with conservative treatment alone.
Interventions
Oral pregabalin administered as adjunctive therapy to standard conservative treatment for chronic pelvic pain. Treatment will begin at 150 mg/day in two divided doses. The dose may be increased by 150 mg/day at intervals of 3 to 7 days according to pain control and tolerability, up to a maximum of 600 mg/day. Once an effective and tolerated dose is established, it will be maintained through the 12-week treatment period. Pregabalin will then be gradually tapered after Week 12 based on the maintenance dose, clinical condition, and withdrawal symptoms.
Standard conservative treatment consisting of a biopsychosocial management approach, including patient education, body awareness therapy, cognitive interventions, individualized clinical advice, and other appropriate conservative care.
Sponsors
Study design
Eligibility
Inclusion criteria
* Women aged 18-65 years. * Diagnosis of chronic pelvic pain based on the 2022 revisions to the European Association of Urology criteria. * Use of, or willingness to use, effective contraception to avoid pregnancy during the study period. * Moderate to severe chronic pelvic pain lasting more than 6 months. Moderate pain is defined as a VAS score of 4-6, and severe pain as a VAS score of 7 or higher. * Sufficient cognitive and language skills to comply with all study requirements.
Exclusion criteria
* Dysmenorrhea as the sole pain complaint. * History of malignancy. * Current or previous use of pregabalin. * Planned surgery within the next 6 months. * Contraindication to pregabalin or a previous adverse reaction to pregabalin. * Current use of gonadotropin-releasing hormone agonists with inability or unwillingness to discontinue treatment. * Pregnancy, breastfeeding, or intention to become pregnant within the next 6 months.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Mean Pain Intensity From Baseline to Week 12 | Baseline to Week 12 | Change in mean chronic pelvic pain intensity measured using a visual analogue scale (VAS), ranging from 0 (no pain) to 10 (worst pain imaginable). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Mean Pain Intensity at Follow-up Visits | Weeks 2, 4, 8, and 12 | Mean pain intensity measured using the VAS at each scheduled follow-up assessment. |
| Pregabalin Dose | Weeks 2, 4, 8, and 12 | Daily pregabalin dose administered to participants in the pregabalin group, recorded at each follow-up assessment. |
| Overall Treatment Satisfaction | Weeks 2, 4, 8, and 12 | Participant-reported overall satisfaction with treatment, assessed using a 5-point Likert scale. |
| Health-related Quality of Life | Weeks 2, 4, 8, and 12 | Physical and mental health-related quality of life assessed using the Short Form-12 (SF-12) questionnaire, scored from 0 to 100, with higher scores indicating better health status. |
| Gynecologic Pain-related Symptoms | Weeks 2, 4, 8, and 12 | Gynecologic pain-related symptoms assessed using the McCormack scale, scored from 0 to 3, with higher scores indicating greater gynecologic pain. |
| Safety outcomes | From treatment initiation through Week 12 and post-treatment safety assessment | Frequency and type of adverse events occurring during the study, including events identified through clinical assessment and participant reporting. |