Home › Trials › NCT05643534

Assessing Tenapanor for Treating IBS-C in Teens

A 12-Week, Randomized, Double-Blind, Placebo-Controlled, Phase 3 Study to Assess the Safety and Efficacy of Tenapanor for the Treatment of Irritable Bowel Syndrome With Constipation (IBS-C) in Pediatric Patients 12 to Less Than 18 Years Old

Phase 3 Interventional Ardelyx · NCT05643534

This study is testing if a new medication called tenapanor can help teens with Irritable Bowel Syndrome and constipation feel better.

Quick facts

PhasePhase 3
Study typeInterventional
Enrollment180 (estimated)
Ages12 Years to 17 Years
SexAll
SponsorArdelyx Industry-sponsored
Locations41 sites (Foley, Alabama and 40 other locations)
Trial IDNCT05643534 on ClinicalTrials.gov

What this trial studies

This clinical trial evaluates the safety and efficacy of tenapanor in pediatric patients aged 12 to less than 18 years with Irritable Bowel Syndrome with Constipation (IBS-C). The study involves a 2-week screening period followed by a 12-week randomized treatment phase where participants receive either tenapanor (25 mg or 50 mg) or a placebo twice daily. Patients will self-report their IBS symptoms using an electronic diary, and their compliance will be monitored throughout the study. Safety assessments will be conducted at regular intervals during the treatment period.

Who should consider this trial

Good fit: Ideal candidates are pediatric patients aged 12 to less than 18 years who meet the Rome IV criteria for IBS-C.

Not a fit: Patients who are not within the specified age range or do not meet the diagnostic criteria for IBS-C may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could significantly improve the management of IBS-C symptoms in pediatric patients.

How similar studies have performed: Other studies have shown promise in treating IBS-C with similar pharmacological approaches, indicating potential for success.

Eligibility criteria

Show full inclusion / exclusion criteria 
Inclusion Criteria:

* ≥12 and \<18 years old
* Patient weighs ≥18 kg at the time the patient provides written assent
* Females of child-bearing potential must have negative pregnancy test at Visit 1 (serum) and Visit 2 (urine) and confirm the use of appropriate contraception (including abstinence).
* Patient meets the Rome IV criteria for child/adolescent diagnosis of IBS-C
* Patient is willing to discontinue any laxatives used in favor of the protocol-permitted rescue medicine (which will only be allowed after 72 hours with no bowel movement)
* Patient meets the entry criteria assessed during the 2-week Screening period.
* Ability of both the patient and parent/guardian/LAR to communicate with the Investigator and to comply with the requirements of the entire study, including an understanding of the assessments in the eDiary and how to use the eDiary device
* Patient must provide written assent and the parent/guardian/LAR must provide written informed consent before the initiation of any study-specific procedures

Exclusion Criteria:

* Functional diarrhea as defined by Rome IV child/adolescent criteria
* IBS with diarrhea (IBS-D), mixed IBS (IBS-M), or unsubtyped IBS as defined by Rome IV child/adolescent criteria
* History of non-retentive fecal incontinence.
* Required manual disimpaction any time prior to randomization (after consent);
* Has both unexplained and clinically significant alarm symptoms (lower gastrointestinal \[GI\] bleeding \[rectal bleeding or heme-positive stool\], iron-deficiency anemia, or any unexplained anemia, or weight loss) and systemic signs of infection or colitis, or any neoplastic process
* Patient has any of the following conditions:

  * Celiac disease, or positive serological test for celiac disease
  * Cystic fibrosis
  * Hypothyroidism that is untreated or treated with thyroid hormone
  * Down's syndrome or any other chromosomal disorder
  * Active anal fissure
  * Anatomic malformations (eg, imperforate anus)
  * Intestinal nerve or muscle disorders (eg, Hirschprung disease)
  * Neuropathic conditions (eg, spinal cord abnormalities)
  * Lead toxicity, hypercalcemia
  * Neurodevelopmental disabilities producing a cognitive delay that precludes comprehension and completion of the daily eDiary (Electronic handheld device)
  * Inflammatory bowel disease
  * Childhood functional abdominal pain syndrome
  * Childhood functional abdominal pain;
  * Poorly treated or poorly controlled psychiatric disorders that might influence his or her ability to participate in the study;
  * Lactose intolerance that is associated with abdominal pain or discomfort
  * History of cancer other than treated basal cell carcinoma of the skin; (Note: Patients with a history of cancer are allowed provided that the malignancy has been in a complete remission for at least 5 years before the Randomization Visit.)
  * History of diabetic neuropathy.
* Use of medications that are known to affect stool consistency (Prohibited Medications), including fiber supplements, anti-diarrheals, cathartics, antacids, opiates, prokinetic drugs, laxatives, enemas, antibiotics during the Screening period; unless specified as rescue medication, and used accordingly as directed by the Investigator.
* Patient has had surgery that meets any of the following criteria:

  * Bariatric surgery for treatment of obesity, or surgery to remove a segment of the GI tract at any time before the Screening Visit;
  * Surgery of the abdomen, pelvis, or retroperitoneal structures during the 6 months before the Screening Visit;
  * An appendectomy or cholecystectomy during the 60 days before the Screening Visit;
  * Other major surgery during the 30 days before the Screening Visit
* History of alcohol or substance abuse
* Participation in other clinical trials within 1 month prior to Screening
* Patient and/or parent/guardian/LAR is involved in the conduct and/or administration of this trial as an investigator, sub-investigator, trial coordinator, or other staff member, or the patient is a first-degree family member, significant other, or relative residing with one of the above persons involved in the trial
* If, in the opinion of the Investigator, the patient is unable or unwilling to fulfill the requirements of the protocol or has a condition, which would render the results uninterpretable

Where this trial is running

Foley, Alabama and 40 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
View on ClinicalTrials.gov → Find more trials like this →
Conditions Irritable Bowel Syndrome With ConstipationIBS-C
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.