Tenapanor for the Treatment of Pediatric Patients With Irritable Bowel Syndrome With Constipation (IBS-C)

Study Overview
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Brief Summary
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Open-label long-term safety study of tenapanor in pediatric patients with IBS-C.

Detailed Description
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Open-label long-term safety study of tenapanor in pediatric patients with IBS-C. Eligible patients who complete the parent study will have an option to enroll in this study. Patients from the parent study will continue tenapanor at the same dose assigned in the parent study which can be titrated to either 50 mg BID or 25 mg BID per guidance in protocol after a patient's first week on the assigned dose. Patients will also return for study visits approximately every 6 weeks for safety assessments.

Official Title
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An Open-Label Long-Term Safety Study of Tenapanor for the Treatment of Irritable Bowel Syndrome With Constipation (IBS-C) in Pediatric Patients 6 to Less Than 18 Years Old

Conditions
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Irritable Bowel Syndrome With Constipation (IBS-C)

Intervention / Treatment
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* Drug: Tenapanor


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ≥6 and <18 years old at enrollment of either parent study Patient completed the parent study immediately with adequate compliance with study procedures in the opinion of the Investigator Females of child-bearing potential must have negative pregnancy test at the last visit of the parent study and confirm the use of appropriate contraception (including abstinence). Subject is ambulatory Written informed consent by parent/guardian/ Legally Authorized Representative (LAR) and a willingness of both subject and parent/guardian/LAR to participate in the study as it is described Exclusion Criteria: Patient discontinued prematurely from the parent study. Any surgery on the stomach, small intestine or colon, excluding appendectomy or cholecystectomy Pregnant or lactating women If, in the opinion of the Investigator, patient is unable or unwilling to fulfill the requirements of the protocol

Ages Eligible for Study
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Minimum Age: 6 Years
Maximum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Health Services Research
Intervention Model: Single Group Assignment
Interventional Model Description: Open label study
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Tenapanor<br>Eligible patients from the parent study will continue tenapanor at the same dose assigned in the parent study which can be titrated to either 50 mg BID or 25 mg BID per Investigator guidance after a patient's first week on the assigned dose. | Drug: Tenapanor<br>* Eligible patients from the parent study will continue tenapanor at the same dose assigned in the parent study. Doses can be titrated to either 50 mg BID or 25 mg BID<br>* Other names: Ibsrela;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of participants with treatment-related adverse events as assessed by MedDRA v26.0 | To evaluate the difference in % adverse events between Placebo and Tenapanor to assess the long term safety | 40 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in alanine aminotransferase (ALT) serum chemistry value (IU/L) | To evaluate change from baseline values in tenapanor group versus placebo to assess long term safety | Change from baseline to week 40 | 
| Change in aspartate aminotransferase (AST) serum chemistry value (IU/L) | To evaluate change from baseline values in tenapanor group versus placebo to assess long term safety | Change from baseline to week 40 | 
| Change in serum creatinine value (mg/dL) | To evaluate change from baseline values in tenapanor group versus placebo to assess long term safety | Change from baseline to week 40 |