Complex oligosaccharides can alter the gut microbiome by aiding in the growth of certain organisms, and possibly, inhibiting others. The synergy with a probiotic may enhance gastrointestinal colonization.

The study will evaluate the synergy of the use of a complex oligosaccharide with and without a probiotic on the human microbiome in healthy volunteers who have received antibiotics. The combination should support general gastrointestinal health.

This study is a multi-dose randomized cohort trial using 18 subjects per cohort for a total of 90 healthy adult volunteers ages 18-75.

Inclusion Criteria:

• Healthy adults between the ages of 18-75 years (subjects must be 18-75 at the time of consent) who can provide proof of vaccination against SARS-CoV-2. Proof may be a physical or electronic record of vaccination or self-attestation (to include approximate vaccination date and manufacturer of vaccine) if a copy of the vaccination record is not available
• Subjects must have a BMI of 18 - 30 at screening visit
• Willingness to complete study specific questionnaires
• Willingness to complete journal to record IP dosing times, Bristol stool scores, and IP flavor questionnaires
• Willingness to complete all study procedures, clinic visits, and provide required biospecimen samples
• Willingness to collect and process stool samples at home and transport stool samples to clinic
• Sexually active females of child-bearing potential must agree to use highly effective methods of contraception during heterosexual intercourse throughout the study period and for three days following discontinuation of IP, whichever comes later. Examples of highly effective methods include the use of two forms of contraception with one being an effective barrier method (e.g., a condom and spermicide used together), or have a vasectomised partner. Abstinence is acceptable as a life-style choice. Female subjects who utilize hormonal contraceptives as one of their birth control methods must have used the same method for at least 3 months before study dosing
• Provide informed consent

Exclusion Criteria:

• Subjects with a BMI of 17 or less or 31 or greater are excluded
• Women who are pregnant or breastfeeding, or intend to become pregnant during the course of this study
• Subjects who intend to take a probiotic during the study
• Subjects with self-reported diarrhea on day 1 prior to dosing, whereby diarrhea is defined as two or more episodes of watery and/or unformed stool within 24 hours
• Alcohol or drug abuse during the last 12 months, including passing a screen for drugs of abuse at screening and day 1 of the study
• Unstable medical condition, in the opinion of the investigator
• Subject with a history of allergy to the study antibiotics
• Clinically significant abnormal laboratory test results at screening
• Subjects who are unable or unwilling to provide stool samples on a regular basis as per study protocol
• Participation in a clinical research trial within 30 days prior to screening
• Unable to give informed consent
• Any condition which may preclude subject's ability to comply with and complete the study or may pose a risk to the health of the subject
• Known carriers of C. difficile prior to study start, as determined by qPCR of stool
• Known carriers of vancomycin-resistant enterococci (VRE) prior to study start, as determined by stool culture
• Subjects with history of lactose intolerance

Healthy Adults, ages 18-75.

up to 7 weeks (D1 through D35)