A Phase 2 interventional study of MHS-1031 and Placebo in Gastroesophageal Reflux, sponsored by Microbiome Health Sciences. Completed at 18 sites in United States. Open to participants aged 18 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-07-27.
Sponsored by Microbiome Health Sciences · Phase 2, Interventional, and Treatment
This study will be conducted as a multi-center, randomized, double-blind, placebo-controlled trial to evaluate the effect of MHS-1031 on heartburn-free days in subjects with GERD-related heartburn symptoms.
MHS-1031 is a specific proprietary digestion-resistant oligosaccharide carbohydrate that serves as a prebiotic.
This study will be conducted as a multi-center, randomized, double-blind, placebo-controlled trial to evaluate the effect of MHS-1031 adjunctive to PPI therapy on heartburn-free days in subjects with GERD-related heartburn symptoms who self-report improvement while on sustained daily PPI therapy. Heartburn-free days will be determined by subject report specific to any of the three questions ("burning feeling behind the breastbone" and/or "pain behind your breastbone" and/or "heartburn"; Questions 1, 2 \& 3 of the RESQ-eD). For purposes of this trial, heartburn-free days are defined as subject report of 'Did Not Have', or 'Very Mild' on each of the three RESQ-eD questions listed above.
All candidate subjects must self-report at least partial response to sustained daily PPI acid suppressive therapy (i.e. 'daily' defined as taking PPIs 5-7 days/week on average). Candidate subjects will be screened for medical history of chronic heartburn that may be associated with other medical conditions, and these subjects will be excluded. The entire study consists of three phases: Remote Screening Phase 2-Week Assessment (SP1), on-site Screening Phase Part 2 (SP2) and Treatment Phase (TP).
Efficacy will be assessed using patient reported outcome (PRO) questionnaires, concomitant medication assessments, and assessment of adverse events, from baseline (determined during Remote Screening Phase 2-Week Assessment) to Treatment Phase Weeks 1-4 and Weeks 5-8. The primary analyses will be conducted to assess the efficacy of MHS-1031 adjunctive to PPI therapy, and separately as monotherapy subsequent to combined PPI and MHS-1031 therapy, in randomized subjects with GERD-related heartburn as determined by the RESQ-eD validated questionnaire, validated for use online.
1,211 studies on the registry are indexed under Gastroesophageal Reflux; 202 are open to participants now.
This study's enrollment of 255 is above the median of 68 across 796 interventional studies indexed under Gastroesophageal Reflux.
Browse Gastroesophageal Reflux studies →Microbiome Health Sciences is the lead sponsor of 3 studies on the registry; none are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Concomitant illness with potential to confound outcome assessments for this study, including, but not limited to:
Any of the following current (within the past 6 months) symptomatic conditions:
Endoscopic evidence of any of the following:
Use of any of the following medications that have not been stable dosing for at least 90 days at time of Screening Call:
Use of GLP-1 agonists (e.g., Dulaglutide (Trulicity), Exenatide, Semaglutide (Ozempic/Wegovy), Liraglutide) or prescription medications used for weight loss within 6 months of Screening Call.
* Current use of potassium-competitive acid blocker (PCAB). PCAB may not be used within one week of screening call.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
A planned gap after a treatment, so that its effects can lessen before the study treatment or a study assessment. Ask the study team and the doctor who prescribed it before changing any medicine.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Postmenopausal
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Washout period
A planned gap after a treatment, so that its effects can lessen before the study treatment or a study assessment. Ask the study team and the doctor who prescribed it before changing any medicine.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
QT and QTc
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Panosyl-isomaltooligosaccharide (PIMO) liquid 1 g (1.5 ml) per day for 8 weeks
Drug: MHS-1031
Placebo liquid (1.5 ml) per day for 8 weeks
Other: Placebo
Study medication will be supplied as a syrup in individual sachets containing 1g (1.5 mL) of MHS-1031. Subjects will be randomized in 2:1 fashion to either study drug (2) or placebo (1)
Also known as: Panosyl-isomaltooligosaccharide
Matching placebo is an oral solution formulated to have a degree of sweetness and acidity similar to the study medication and will be provided in equivalent sachets containing 1.5g (1.5 mL) of the oral placebo solution.
Heartburn-free days/week
The difference between baseline weekly average heartburn-free days and weekly average heartburn-free days during Treatment Phase Weeks 1-4 and Weeks 5-8 (as measured using questions 1, 2 and 3 of the Reflux Symptom Questionnaire Electronic Diary) (RESQ-eD).
Time frame: 4 and 8 weeks
Heartburn symptom severity
The difference between baseline daily average heartburn symptom severity score and daily average heartburn symptom severity score during Treatment Phase Weeks 1-4 and Treatment Phase Weeks 5-8 (as measured using questions 1, 2 and 3 of the Reflux Symptom Questionnaire Electronic Diary) (RESQ-eD).
Time frame: 4 and 8 weeks
Heartburn-free day satisfaction
Any increase between baseline weekly average heartburn-free days and heartburn-free days during Treatment Phase Weeks 1-4 and Weeks 5-8 where Patient Global Assessment Question 1 is ≥ baseline.
Time frame: 4 and 8 weeks
GERD-related severity satisfaction
Any increase between baseline daily average heartburn severity and heartburn severity during Treatment Phase Weeks 1-4 and Weeks 5-8 where Patient Global Assessment Question 1 is ≥ baseline.
Time frame: 4 and 8 weeks
Plan to share: No
No publications or documents are linked to this record.
This study is completed, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.
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