Human Milk Oligosaccharides (HMOs) for Irritable Bowel Syndrome (IBS)

Inclusion Criteria: 1. Written informed consent obtained before any trial related assessments are performed. 2. Male or female aged ≥18 years at the time of consent. a. Female participants of child-bearing potential (females who are post-menopausal, i.e., when there has been no menstruation for a minimum of 12 months prior to screening, are considered not to be of child-bearing potential.), who are not surgically sterilized, must have a negative pregnancy test at screening and be willing to practice one of the following appropriate contraceptive methods until the last visit: i. Sexual abstinence. ii. Oral contraceptives. iii. Trans dermal patches or depot injection of a progestogen drug (starting at least 4 weeks prior to product administration). iv. Double barrier method: condom or occlusive cap (diaphragm or cervical/vault caps) plus spermicidal agent. v. Intrauterine device (IUD), intrauterine system (IUS), subdermal implant, or vaginal ring (placed at least 4 weeks prior to product administration). vi. Contraceptives must be effective before the randomization visit. However, national requirements should always be followed. 3. IBS-D or IBS-C or IBS-M according to Rome IV criteria. This will be established by using the IBS Module of the Rome IV Diagnostic Questionnaire, and requires recurrent abdominal pain on average at least 1 day per week during the previous 3 months that is associated with two or more of the following: 1. Related to defecation (may be increased or unchanged by defecation) on at least 30% of pain instances in past 3 months. 2. Associated with a change in stool frequency (on at least 30% of pain instances in past 3 months). 3. Associated with a change in stool form or appearance (on at least 30% of pain instances in past 3 months). 4. Reported IBS diagnosis from a physician. 5. Personal access to the internet via computer, tablet, or smart-phone. 6. Be willing and able to comply with trial protocol, including entry of electronic diary data for at least 12 out of 14 diary days during the pre-randomization baseline 2-week run-in diary period (between V1 andV2). Inclusion criteria Visit 2: To be eligible for inclusion, the participant must fulfil all of the following criteria: 7. Scores of 1, 2, 6, or 7 on the Bristol stool scale at least twice per week \[as determined by eDiary completion between V1 and V2\]. 8. An average baseline of worst abdominal pain of ≥3.3 (NRS-11) during the 2-week run-in period prior to randomization \[as determined by eDiary completion between V1 and V2\]. Exclusion Criteria: The presence of any of the following criteria will exclude the participant from participating in the trial: 1. Treatment with an investigational drug from another clinical trial within 30 days/5 half- lives of the drug (which ever longest) prior to screening visit. 2. Any known gastrointestinal disease(s) or medical history that may interfere with the trial evaluations in the opinion of the investigator, in particular: 1. Coeliac disease. 2. IBD. 3. Diverticulitis. 4. C. difficile infection reported in the previous 2 years. 5. Any clinically symptomatic biochemical or structural abnormality or active disease of the gastrointestinal tract within 6 months before screening, including daily diarrhea within two weeks prior to the screening interview or during the screening/baseline period. 6. Substance abuse (within past 2 years). 7. New use of antibiotics (within past 2 months), prebiotics, probiotics, or fiber supplements (within the past month). 8. Hepatic dysfunction assessed as part of the blood safety panel (defined as alanine aminotransaminase/serum glutamic-pyruvic transaminase or aspartate aminotransaminase/serum glutamic-oxaloacetic transaminase \>2.5 x the upper limit of normal, or a history of hepatobiliary disease) or renal impairment (serum creatinine) \>2 mg/dl); any surgery (within a year of screening) on the stomach, small intestine, or colon (excluding appendectomy, hernia surgery not involving the GI tract, or c-section). 9. Any history of pancreatitis (either acute or chronic). 10. Laxative abuse (use of more than recommended dosage). 11. Pregnant or lactating individuals. 12. Any other gastrointestinal disease(s) or medical history that may interfere with the trial evaluations in the judgment of the investigator. 3. Following strict diets to improve their IBS symptoms as judged by the investigator e.g., Low FODMAP (within past 2 months). Exclusion based on diet will be reviewed by single investigator for consistency. 4. Any clinically relevant chronic disease(s) such as malignancy, diabetes, severe coronary disease, kidney disease, autoimmune or neurological disease, that in the opinion of the investigator would interfere with the trial evaluations or the safety of the participant. 5. Current severe psychiatric disease and/or psychological disturbance, a major psychiatric disorder requiring hospitalization in the last 3 years, or a history of attempted suicide or uncontrolled bipolar disorder; or clinical evidence of any significant psychiatric disease or symptoms that may interfere with the participant successfully completing the trial. 6. Treatment with restricted and prohibited concomitant medications. 7. Diagnosed with and treated for IBS for more than 10 years 8. Has a business or personal relationship with trial staff or sponsor who is directly involved with the conduct of the trial. 9. Lack of suitability for participation in the study for any reason as judged by the investigator. 10. Has previously been randomized into this trial, is participating in this trial at another investigational site or is planning to participate in any other clinical trial during this trial. 11. Desire and/or plans on changing current diet regime during the participation of this trial.