Vaginal Baclofen Suppositories in Chronic Pelvic Pain

Baclofen in Chronic Pelvic Pain, a Randomized, Double-Blind, Placebo Controlled Trial

The purpose of this study is to evaluate if baclofen vaginal suppositories improve symptoms of Chronic Pelvic Pain (CPP).

Participants in this study will take four short questionnaires prior to being randomized. Randomization is like flipping a coin; participants have an equal likelihood of being randomized to the treatment group (vaginal baclofen suppositories) or placebo group (vaginal suppository without baclofen ingredient). Participants will take their assigned treatment nightly for 8 weeks. Follow up visits will be at the 4 and 8 week time frames, when questionnaires will again be completed. Participants may receive additional treatments for CPP during the course of the study. After 8 weeks Participants will be offered a prescription for baclofen suppositories and the study drug will be stopped. Follow up on patient symptoms with questionnaires will again occur at 12 weeks.

Study Overview

• Status: Completed
• Conditions: Chronic Pelvic Pain Syndrome
• Intervention / Treatment: Drug: 20 mg baclofen vaginal suppository daily per vagina; Drug: Placebo

Detailed Description

Study Design/Methodology

This is a single center, double-blinded, placebo-controlled, randomized trial. Women will be recruited from a subspecialty clinic at the University of Louisville and be eligible for participation if they meet the diagnosis of Chronic Pelvic Pain and are between the ages of 18-65 years old. Eligible, consenting participants will undergo randomization with equal probability of assignment to one of the two groups:

1. Baclofen 20mg vaginal suppository daily per vagina and
2. placebo.

Participants will be blinded to study allocation. Baclofen or placebo suppositories will be continued to 8 weeks, at which time all participants will be offered a baclofen suppository prescription. Patients will then follow up at the 12 week mark and whether they continued baclofen suppositories and pill count will be recorded in addition to the below questionnaires.

Clinical outcomes and questionnaires will be assessed at baseline and after 4, 8, and 12 weeks of treatment. Participants will be randomized with a stratified block randomization scheme (with a random block size of 4, 6, and 8 participants).

Participants will be required to come in for at least 1 visit at 8 weeks to assess pelvic muscle dysfunction and perform pill count.

We hypothesize a significant change in PROMIS Pain Interference score, patient satisfaction, PROMIS global health scores, and PROMIS sexual function scores for patients assigned to the baclofen treatment arm.

Inclusion Criteria:

• Women ages 18-65 years old
• Women are not sexually active, sexually active with same sex partners or are on effective contraception
• Diagnosed with Chronic Pelvic Pain

Exclusion Criteria:

• Gross hematuria
• Currently pregnant or breastfeeding
• Unable to speak and read English
• History of allergic reaction to baclofen tablet
• History of allergic reaction to components of placebo (coconut oil)
• History of gastrointestinal, genitourinary, or pelvic cancer in the last 5 years

• Study Type: Interventional
• Enrollment (Actual): 39
• Phase: Phase 2

Contacts and Locations

Study Locations

• United States
  • Kentucky
    • Louisville, Kentucky, United States, 40205
      • ULP Female Pelvic Medicine and Reconstructive Surgery - Springs Medical Center Suite 190

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Women ages 18-65 years old
• Women are not sexually active, sexually active with same sex partners or are on effective contraception
• Diagnosed with Chronic Pelvic Pain

Exclusion Criteria:

• Gross hematuria
• Currently pregnant or breastfeeding
• Unable to speak and read English
• History of allergic reaction to baclofen tablet
• History of allergic reaction to components of placebo (coconut oil)
• History of gastrointestinal, genitourinary, or pelvic cancer in the last 5 years

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Vaginal baclofen suppository; Baclofen 20mg in Supposibase F vaginal suppository daily per vagina	Drug: 20 mg baclofen vaginal suppository daily per vagina; 20 mg baclofen vaginal suppository in Supposibase F daily per vagina - to be compounded by The Louisville Compounding Pharmacy
Placebo Comparator: Vaginal placebo suppository; Supposibase F vaginal suppository daily per vagina	Drug: Placebo; Vaginal suppository composed of Supposibase F daily per vagina

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Visual analogue Score (VAS) 1-100 for pain	VAS is a 1-100mm scale with lower scores indicating less pain	at 8 weeks of suppository use

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Patient-Reported Outcomes Measurement Information System (PROMIS) Pain Interference score	Patient-Reported Outcomes Measurement Information System (PROMIS) pain interference score is a 40-200 point scale with lower values indicating lower pain interference with quality of life	at baseline and at 4, 8 and 12 weeks
Pelvic floor impact questionnaire	pelvic floor impact questionnaire is a 0-63 point composite scale consisting of questions concerning bladder/urinary, bowel/rectal, and vaginal/pelvic symptoms with higher values indicating higher symptoms	at baseline and at 4, 8, and 12 week follow up
Pelvic floor disability index (PFDI) questionnaire	the pelvic floor disability index (PFDI) questionnaire is a composite questionnaire on a 0-80 point scale containing questions regarding pelvic organ prolapse, colorectal/anal distress, and urinary distress questions with higher scores indicating higher symptoms	at baseline and at 4, 8, and 12 week follow up
Visual analogue Score (VAS) 1-100 for pain	VAS is a 1-100mm scale with lower scores indicating less pain	at baseline and at 4 and 12 week follow up
O'Leary Sant questionnaire	O'Leary Sant questionnaire is a 0 to 37 point score with higher points indicating increased symptoms	at baseline and at 4, 8, and 12 week follow up
Patient-Reported Outcomes Measurement Information System (PROMIS) global health score	Patient-Reported Outcomes Measurement Information System (PROMIS) global health score is a 9-45 point scale with higher scores indicating better overall health and quality of life	at baseline and at 4, 8, and 12 week follow up
Overall Satisfaction	Overall Satisfaction is a yes/no questionnaire with if "yes" is selected one selects choices from "somewhat" to "quite a bit" in satisfaction. "quite a bit" would indicate greater satisfaction.	at 4, 8, and 12 week follow up
Patient-Reported Outcomes Measurement Information System (PROMIS) Sexual function score	Patient-Reported Outcomes Measurement Information System (PROMIS) Sexual function score is a 9-36 point score with higher scores indicating higher bother related to sexual function	at 0, 4, 8, and 12 week follow up
Number of other treatments for chronic pelvic pain during the trial period	Number of other treatments for chronic pelvic pain during the trial period to determine if results are clouded by other, appropriate, evidence based treatments received for chronic pelvic pain.	at 4, 8, and 12 week follow up
Pill Count	Pill Count to determine how many doses of the study medication have been missed	at 4, 8, and 12 week follow up

Collaborators and Investigators

• Sponsor: University of Louisville
• Investigators: Study Director: Rodger W Rothenberger, MD, University of Louisville

Publications and helpful links

General Publications

• Moldwin RM, Fariello JY. Myofascial trigger points of the pelvic floor: associations with urological pain syndromes and treatment strategies including injection therapy. Curr Urol Rep. 2013 Oct;14(5):409-17. doi: 10.1007/s11934-013-0360-7.
• Messelink B, Benson T, Berghmans B, Bo K, Corcos J, Fowler C, Laycock J, Lim PH, van Lunsen R, a Nijeholt GL, Pemberton J, Wang A, Watier A, Van Kerrebroeck P. Standardization of terminology of pelvic floor muscle function and dysfunction: report from the pelvic floor clinical assessment group of the International Continence Society. Neurourol Urodyn. 2005;24(4):374-80. doi: 10.1002/nau.20144. No abstract available.
• Lamvu G, Carrillo J, Ouyang C, Rapkin A. Chronic Pelvic Pain in Women: A Review. JAMA. 2021 Jun 15;325(23):2381-2391. doi: 10.1001/jama.2021.2631.
• Meister MR, Sutcliffe S, Ghetti C, Chu CM, Spitznagle T, Warren DK, Lowder JL. Development of a standardized, reproducible screening examination for assessment of pelvic floor myofascial pain. Am J Obstet Gynecol. 2019 Mar;220(3):255.e1-255.e9. doi: 10.1016/j.ajog.2018.11.1106. Epub 2018 Dec 7.
• Brawn J, Morotti M, Zondervan KT, Becker CM, Vincent K. Central changes associated with chronic pelvic pain and endometriosis. Hum Reprod Update. 2014 Sep-Oct;20(5):737-47. doi: 10.1093/humupd/dmu025. Epub 2014 Jun 11.
• Mathias SD, Kuppermann M, Liberman RF, Lipschutz RC, Steege JF. Chronic pelvic pain: prevalence, health-related quality of life, and economic correlates. Obstet Gynecol. 1996 Mar;87(3):321-7. doi: 10.1016/0029-7844(95)00458-0.
• Chronic Pelvic Pain: ACOG Practice Bulletin, Number 218. Obstet Gynecol. 2020 Mar;135(3):e98-e109. doi: 10.1097/AOG.0000000000003716.
• Doggweiler R, Whitmore KE, Meijlink JM, Drake MJ, Frawley H, Nordling J, Hanno P, Fraser MO, Homma Y, Garrido G, Gomes MJ, Elneil S, van de Merwe JP, Lin ATL, Tomoe H. A standard for terminology in chronic pelvic pain syndromes: A report from the chronic pelvic pain working group of the international continence society. Neurourol Urodyn. 2017 Apr;36(4):984-1008. doi: 10.1002/nau.23072. Epub 2016 Aug 26.
• Shafrir AL, Martel E, Missmer SA, Clauw DJ, Harte SE, As-Sanie S, Sieberg CB. Pelvic floor, abdominal and uterine tenderness in relation to pressure pain sensitivity among women with endometriosis and chronic pelvic pain. Eur J Obstet Gynecol Reprod Biol. 2021 Sep;264:247-253. doi: 10.1016/j.ejogrb.2021.07.029. Epub 2021 Jul 22.
• Frederice CP, Brito LGO, Pereira GMV, Lunardi ALB, Juliato CRT. Interventional treatment for myofascial pelvic floor pain in women: systematic review with meta-analysis. Int Urogynecol J. 2021 May;32(5):1087-1096. doi: 10.1007/s00192-021-04725-x. Epub 2021 Feb 27.
• Stone RH, Abousaud M, Abousaud A, Kobak W. A Systematic Review of Intravaginal Diazepam for the Treatment of Pelvic Floor Hypertonic Disorder. J Clin Pharmacol. 2020 Dec;60 Suppl 2:S110-S120. doi: 10.1002/jcph.1775.
• Juergens S. Alprazolam and diazepam: addiction potential. J Subst Abuse Treat. 1991;8(1-2):43-51. doi: 10.1016/0740-5472(91)90026-7.
• Das S, Palappalllil DS, Purushothaman ST, Rajan V. An Unusual Case of Baclofen Abuse. Indian J Psychol Med. 2016 Sep-Oct;38(5):475-476. doi: 10.4103/0253-7176.191383.
• Amtmann D, Kim J, Chung H, Askew RL, Park R, Cook KF. Minimally important differences for Patient Reported Outcomes Measurement Information System pain interference for individuals with back pain. J Pain Res. 2016 Apr 27;9:251-5. doi: 10.2147/JPR.S93391. eCollection 2016.

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2024
• Primary Completion (Actual): January 1, 2026
• Study Completion (Actual): January 1, 2026

Study Registration Dates

• First Submitted: May 12, 2023
• First Submitted That Met QC Criteria: July 21, 2023
• First Posted (Actual): August 1, 2023

Study Record Updates

• Last Update Posted (Actual): May 1, 2026
• Last Update Submitted That Met QC Criteria: April 27, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Baclofen; vaginal suppository; pelvic floor muscle dysfunction
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Pelvic Pain; Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Peripheral Nervous System Agents; Neurotransmitter Agents; GABA Agents; Neuromuscular Agents; Muscle Relaxants, Central; GABA Agonists; GABA-B Receptor Agonists; Baclofen
• Other Study ID Numbers: 22.1000

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

IPD Plan Description

This study information will be sourced from the subjects. Identifying information and data collected during this study will be kept secure and confidential. For confidentiality, only research team members will have access to the study information in the database. Subjects will be assigned a unique study ID that will be used on all case report forms and database reporting. The database that will be used is REDCap which is HIPPA (Health Insurance Portability and Accountability Act of 1996) compliant, encrypted, and password protected. Any hard copies will be maintained in a locked cabinet in a locked office by a member of the research team.

The research personnel in this study are CITI and HIPAA trained. If new research personnel are added, an amendment will be submitted to and approved by the IRB before being allowed to participate in the study

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: Yes