Trial Evaluating Nutritional Fiber in Digestive Symptoms of Endometriosis (TEND)

November 9, 2026 updated by: LOAM Science

A Randomized, Double-Blind, Placebo-Controlled Study to Evaluate the Safety, Tolerability, and Mechanistic Effects of a Multi-Fiber Prebiotic Dietary Supplement (LOAM) on the Gut and Vaginal Microbiome, Gastrointestinal Well-Being, and Quality-of-Life Parameters in Women With Endometriosis and Co-Existing Gastrointestinal Symptoms

This study is a double-blind, randomized, placebo-controlled study that evaluates the safety and tolerability of a fiber-based dietary supplement and the mechanistic and structure-function effects of that supplement on the gut and vaginal microbiome, gastrointestinal well-being, and quality-of-life parameters in 140 women with endometriosis and co-existing gastrointestinal symptoms over 12 weeks. The primary objective is to evaluate the safety and tolerability of the supplement, measured by the incidence and severity of gastrointestinal adverse events (AEs) and discontinuations. Secondary objectives include assessing the fibers impact on gastrointestinal symptoms and quality of life through the use of custom questionnaires built for the study population and evaluation of other endometriosis related parameters such as pelvic discomfort. Exploratory objectives focus on the exploration of the gut and vaginal microbiomes, their connection to endometriosis, and how they are impacted by the study product.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
140

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Locations

  • United States
    • California
      • San Francisco, California, United States, 94109
        • Recruiting
        • Alethios
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years to 45 years (Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

Female

Description

Inclusion Criteria:

  • Confirmed diagnosis of endometriosis (by imaging, laparoscopy, or physician clinical assessment).
  • Enriched gastrointestinal phenotype: self-reported gastrointestinal symptoms on at least 3 days per week for the preceding 3 months, including at least one of bloating, constipation, or abdominal discomfort
  • Predominantly Bristol Stool Scale Type 1-3 (constipation-predominant), or self-reported bloating as a dominant symptom.
  • Stable hormonal status: either no hormonal therapy, or stable hormonal therapy (combined oral contraceptive, progestin, or GnRH analogue) for at least 3 months with no planned change during the study.
  • Estimated habitual dietary fiber intake below 25 g/day based
  • Willingness to share menstrual cycle data.
  • Willing to maintain stable diet, physical activity, and medication regimens throughout the study.
  • Able to provide electronic informed consent and to comply with stool and vaginal self-sampling procedures.
  • Ownership and consistent use of a home body-weight scale for the duration of the study, to support the standardized at-home morning weighing protocol.

Exclusion Criteria:

  • Inflammatory bowel disease (Crohn's disease, ulcerative colitis), celiac disease, or other organic gastrointestinal disease.
  • Severe irritable bowel syndrome (IBS) requiring active pharmacological management. Mild-to-moderate overlap is permitted as part of the enrichment strategy.
  • Antibiotic use within 8 weeks prior to baseline or anticipated during the study.
  • Probiotic, prebiotic, or fiber supplement use within 4 weeks prior to baseline (washout required).
  • Major gastrointestinal surgery, excluding appendectomy or cholecystectomy more than 6 months prior, and excluding surgical intervention for endometriosis.
  • Current pregnancy, breastfeeding, or plans to conceive during the study.
  • Severe constipation requiring regular prescription laxatives.
  • Significant renal, hepatic, cardiac, or endocrine disease.
  • Active malignancy.
  • Known allergy or intolerance to any LOAM fiber component.
  • Significant dietary change or weight-loss intervention within the preceding 3 months.
  • Use of medications known to significantly alter gut motility or the microbiome (for example, recent metformin initiation, regular opioid use, or chronic proton-pump inhibitor use), per investigator judgment.
  • Any surgical intervention for endometriosis (including laparoscopy, laparotomy, or endometrioma excision) within the 6 months prior to screening, as post-surgical physiological changes may confound symptom and biomarker assessments.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

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

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Fiber Supplement

Fiber supplement providing 20 grams/day of dietary fiber. Taken as a scoop of powder added to a drink twice daily.
Dietary supplement: Fiber

Dietary fiber blend containing six prebiotic fibers.
Placebo Comparator: Placebo Control

Placebo control. Taken as a scoop of powder added to a drink twice daily.
Dietary supplement: Placebo

Placebo control

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Incidence and severity of GI adverse events (AEs) and discontinuations.
Time Frame: An adverse event questionnaire will be administered at baseline and at Week 4, Week 6, Week 8, and Week 12 of supplementation. Adverse events will also be collected ad hoc throughout the study period via a reporting form.

To evaluate the safety and tolerability of the fiber blend.
An adverse event questionnaire will be administered at baseline and at Week 4, Week 6, Week 8, and Week 12 of supplementation. Adverse events will also be collected ad hoc throughout the study period via a reporting form.

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Changes in a custom gut health questionnaire
Time Frame: From baseline sample collection through the end of supplementation (Baseline, Week 4, Week 6, Week 8, and Week 12).

A custom gut health questionnaire using a 5-point Likert Scale (1-5) where 1 is no symptoms and 5 is the worst symptoms designed to evaluate GI symptoms relevant to endometriosis.
From baseline sample collection through the end of supplementation (Baseline, Week 4, Week 6, Week 8, and Week 12).
DASS-21
Time Frame: From baseline sample collection through the end of supplementation (Baseline, Week 4, Week 6, Week 8, and Week 12).

Self-reported mental health tool to evaluate depression, anxiety, and stress that uses a 4-point Likert Scale (0-3) where 0 is not applicable and 3 is highly applicable.
From baseline sample collection through the end of supplementation (Baseline, Week 4, Week 6, Week 8, and Week 12).
Pelvic discomfort duration over 24 hours
Time Frame: From baseline sample collection through the end of supplementation (Daily).

Evaluation of pelvic discomfort associated with endometriosis over the previous 24 hours using a 0-24 scale, where 0 is no hours of pelvic discomfort and 24 is pelvic discomfort for the entire duration of the last 24 hours.
From baseline sample collection through the end of supplementation (Daily).
Pelvic discomfort severity
Time Frame: From baseline sample collection through the end of supplementation (daily).

Pelvic discomfort severity assessed using a 10 point numerical rating scale (0-10) with zero being no discomfort and ten being the highest level of discomfort.
From baseline sample collection through the end of supplementation (daily).
Body Weight
Time Frame: From baseline sample collection through the end of supplementation (Baseline, Week 4, Week 6, Week 8, and Week 12).

Performed at home using a scale
From baseline sample collection through the end of supplementation (Baseline, Week 4, Week 6, Week 8, and Week 12).

Other Outcome Measures

Other Outcome Measures

For clinical trials, a planned measurement described in the protocol that is used to determine the effect of an intervention/treatment on participants. For observational studies, a measurement or observation that is used to describe patterns of diseases or traits, or associations with exposures, risk factors, or treatment. Types of outcome measures include primary outcome measure and secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Gut Microbiome Composition
Time Frame: Three separate samplings, one at baseline, one at six weeks, and one at 12 weeks.

Evaluation of the gut microbiome composition using shotgun metagenomic sequencing.
Three separate samplings, one at baseline, one at six weeks, and one at 12 weeks.
Gut Microbiome Function
Time Frame: Three separate samplings, one at baseline, one at six weeks, and one at 12 weeks.

Evaluation of the gut microbiome function using shotgun metagenomic sequencing.
Three separate samplings, one at baseline, one at six weeks, and one at 12 weeks.
Vaginal Microbiome Composition
Time Frame: Three separate samplings, one at baseline, one at six weeks, and one at 12 weeks.

Evaluation of the vaginal microbiome composition using shotgun metagenomic sequencing.
Three separate samplings, one at baseline, one at six weeks, and one at 12 weeks.
Custom endometriosis quality of life survey
Time Frame: From baseline sample collection through the end of supplementation (Baseline, Week 4, Week 6, Week 8, and Week 12).

A custom survey designed to assess the impact of endometriosis on an individuals quality of life. Questions are scored using a 5-point Likert Scale (1-5) where 1 is no impact on quality of life and 5 is the highest level of impact.
From baseline sample collection through the end of supplementation (Baseline, Week 4, Week 6, Week 8, and Week 12).
Vaginal Microbiome Function
Time Frame: Three separate samplings, one at baseline, one at six weeks, and one at 12 weeks.

Evaluation of the vaginal microbiome function using shotgun metagenomic sequencing.
Three separate samplings, one at baseline, one at six weeks, and one at 12 weeks.
Endometriosis-related Medication Use
Time Frame: From enrollment through the conclusion of supplementation (Baseline, Week 4, Week 6, Week 8, and Week 12).

Medication use assess by open-ended questionnaire.
From enrollment through the conclusion of supplementation (Baseline, Week 4, Week 6, Week 8, and Week 12).
Deep dyspareunia
Time Frame: From baseline through the conclusion of supplementation (Baseline, Week 4, Week 6, Week 8, and Week 12).

Deep dyspareunia severity assessed using a 10 point numerical rating scale (0-10) with zero being no discomfort and ten being the highest level of discomfort.
From baseline through the conclusion of supplementation (Baseline, Week 4, Week 6, Week 8, and Week 12).
Dysmenorrhea
Time Frame: From baseline through the conclusion of supplementation (daily).

Dysmenorrhea severity assessed using a 10 point numerical rating scale (0-10) with zero being no discomfort and ten being the highest level of discomfort.
From baseline through the conclusion of supplementation (daily).
Non-menstrual pelvic discomfort
Time Frame: From baseline through the conclusion of supplementation (Baseline, Week 4, Week 6, Week 8, and Week 12).

Non-menstrual pelvic discomfort severity assessed using a 10 point numerical rating scale (0-10) with zero being no discomfort and ten being the highest level of discomfort.
From baseline through the conclusion of supplementation (Baseline, Week 4, Week 6, Week 8, and Week 12).
Dyschezia
Time Frame: From baseline through the conclusion of supplementation (daily).

Dyschezia severity assessed using a 10 point numerical rating scale (0-10) with zero being no discomfort and ten being the highest level of discomfort.
From baseline through the conclusion of supplementation (daily).
Productivity Impairment
Time Frame: From baseline through the conclusion of supplementation (Baseline, Week 4, Week 6, Week 8, and Week 12).

Measured using the Work Productivity and Activity Impairment Questionnaire, which includes open ended questions to assess hours missed as well as personal assessments of productivity using a 10 point numerical rating scale (0-10) with zero being no effect and ten being highly impacted.
From baseline through the conclusion of supplementation (Baseline, Week 4, Week 6, Week 8, and Week 12).
Bloating severity and abdominal girth
Time Frame: From baseline through the conclusion of supplementation (Baseline, Week 4, Week 6, Week 8, and Week 12).

Bloating severity assessed using a 10 point numerical rating scale (0-10) with zero being no bloating and ten being the highest level of bloating and abdominal girth measured by tape measure.
From baseline through the conclusion of supplementation (Baseline, Week 4, Week 6, Week 8, and Week 12).

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
LOAM Science

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
Alethios, Inc.

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Bryce Jarman, PhD, LOAM Science

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
October 20, 2026

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
June 1, 2027

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
September 1, 2027

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
October 6, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
October 13, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
October 15, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
November 12, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 9, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
October 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • LOA001

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

The data is proprietary data.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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