Clinical trial NCT06810167: Assessing Tenapanor as a Treatment of CF-related Constipation.
Official title: An Open-label, Single Center Study Assessing Tenapanor as a Non-CFTR-mediated Treatment of CF-related Constipation in People With CF.
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: PHASE3
Conditions: Cystic Fibrosis
Constipation
Keywords: Constipation
Cystic Fibrosis
CFrC
Lead sponsor: Massachusetts General Hospital
Sponsor class: OTHER
Collaborators: name: Ardelyx
First posted: 2025-02-05
Enrollment: 25
Sex: ALL
Minimum age (years): 18
Maximum age (years): 75
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: TREATMENT

Brief summary: Tenapanor is the newest FDA-approved drug for IBS with constipation (IBS-C). This study seeks to understand tenapanor as a treatment for cystic fibrosis-related constipation (CFrC) in CF patients. Participants will ingest one 50 mg tablet of tenapanor, twice daily, for a 4-week treatment period. They will also complete three questionnaires, the PAC-SYM, PAC-QoL, and IBS-SSS, and daily diaries to characterize GI symptom burden and spontaneous bowel movement (SBM) frequency.


Eligibility criteria: Inclusion Criteria:

1. Having confirmed cystic fibrosis (either by sweat chloride or genetic testing)
2. Meeting criteria for CFrC

   Must include 2 of the following, with or without abdominal pain for at least 3 months, with symptom onset at least 6-months prior:
   * Straining in at least 25% of defecations
   * Bristol Stool Scale 1-2 more than 25% of defecations (change in stool form)
   * Sensation of incomplete evacuation more than 25% of defecations
   * Sensation of anorectal obstruction/blockage more than 25% of defecations
   * Manual disimpaction/manipulation of pelvic floor to facilitate more than 25% of defecations
   * Fewer than 3 spontaneous bowel movements weekly (change in stool frequency)
   * Loose stools rarely present without the use of laxatives
3. Willingness to avoid major dietary or lifestyle changes during study.

Exclusion Criteria:

1. Use of any antibiotic to treat infection within the 4-weeks prior to study initiation (stable azithromycin dosed 3-times weekly for lung function is to be allowed)
2. Inability to discontinue standing bowel regimen (including fiber, stool softener, as well as either osmotic or stimulant laxative, pro-kinetic serotonergic agents, or other therapy) 2-weeks prior to study drug initiation (with ability to use osmotic laxative therapy as rescue therapy only).
3. Severe CFrC as determined by study team
4. Prior tenapanor usage
5. Hospitalization within 4-weeks prior to study initiation.
6. DIOS within 4-weeks prior to study initiation.
7. Other known/suspected mechanical obstruction

Primary outcomes:
measure: Increase in SBM frequency
timeFrame: Patients will record SBM frequency over the 4-week treatment period.
Secondary outcomes:
measure: Change in PAC-SYM questionnaire score
timeFrame: Patients will complete the PAC-SYM at -2 weeks, 0 weeks, 2 weeks, and 4 weeks.
measure: Change in PAC-QOL questionnaire score
timeFrame: Patients will complete the PAC-QOL at -2 weeks, 0 weeks, 2 weeks, and 4 weeks.
measure: Change in IBS-SSS questionnaire score
timeFrame: Patients will complete the IBS-SSS at -2 weeks, 0 weeks, 2 weeks, and 4 weeks.
Other outcomes:
Locations:
city: Boston
country: United States
facility: Massachusetts General Hospital
state: Massachusetts
Study officials:
affiliation: Massachusetts General Hospital
name: Christoher D Velez, MD
role: PRINCIPAL_INVESTIGATOR
References: