Baby 2 Baby Beneficial Bacteria

NCT05703659 | Terminated

• 1 other identifier: IRB202200652
• Study Type: interventional
• Target: 10
• Locations: 1 country
• Sites: 1

Brief Summary

The investigators will recruit mother-infant dyads to attend weekly lactation support groups and randomize infants to receive either an HMO consuming or non-HMO consuming probiotic. The investigators will collect infant stool before and after support group attendance. The investigators will use qPCR and metagenomic sequencing to test if the study probiotics or other bacteria transmit between infants. The investigators anticipate HMO consuming bacteria will and non-HMO consuming bacteria will not transmit between infants.

Conditions

Transmission

Keywords

Transmission; Beneficial bacteria; Probiotic; B. longum subsp. infantis; L. reuteri; breastfed infants

Outcome Measures

Primary Outcomes (1)

• Transmission of probiotics to non-supplemented infants

  Percentage of infants with detectable levels of B. infantis who were not given a B. infantis probiotic and were not colonized by B. infantis at baseline OR percentage of infants with detectable levels of L. reuteri who were not given an L. reuteri probiotic and were not colonized by L. reuteri at baseline.

  4 weeks

Study Arms (2)

HMO consuming bacteria

EXPERIMENTAL

Infants will given a daily HMO consuming probiotic (B. infantis) for four weeks

Dietary Supplement: B. longum subsp. infantis

Non-HMO consuming bacteria

EXPERIMENTAL

Infants will be given a daily non-HMO consuming probiotic (L. reuteri) for four weeks

Dietary Supplement: L. reuteri probiotic

Interventions

B. longum subsp. infantis DIETARY_SUPPLEMENT

Infants will receive 1 dose of a B. infantis probiotic daily for 4 weeks

HMO consuming bacteria

L. reuteri probiotic DIETARY_SUPPLEMENT

Infants will receive 1 dose of an L. reuteri probiotic daily for 4 weeks

Non-HMO consuming bacteria

Eligibility Criteria

• Age: 18 Years - 62 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Healthy singleton pregnancy, term delivery (\>= 36 weeks corrected gestational age)
• Maternal intent to exclusively breastfeed for the first six months of infant life (intent to breastfeed for six months correlates with longer duration of breastfeeding, this increases the chance that mothers will still be breastfeeding at the end of the study)
• Maternal vaccination against COVID19 (2 doses Pfizer or Moderna and within 6 months of second dose or 2 doses Pfizer or Moderna and booster.) COVID vaccination is required for maternal participation as this is a study meant to enable transmission of beneficial bacteria species between infants, and infants are too young to be vaccinated.

You may not qualify if:

• Maternal drug abuse
• Infant congenital abnormalities
• Infant age greater than 1 month at first lactation support group meeting (younger infants will have less developed microbiomes, increasing the chance of successful transmission of bacteria)
• Intent to provide a non-study probiotics to the infant
• Known immunocompromised status of the infant.

Sponsors & Collaborators

• University of Florida: lead

Study Sites (1)

University of Florida

Gainesville, Florida, 32611, United States

Location

Study Officials

• Diana Taft, BA, PhD

  University of Florida

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: OTHER
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Primary Purpose of this study is epidemiological, and to determine if probiotic species can transmit between infants whose microbiomes are still developing. Mothers and infant dyads will be enrolled and attend 5 weekly lactation support group sessions. After the first session, infants will be randomized to receive 1 of 2 probiotics. Both probiotics are marketed in the US as dietary supplements for infants. At the first support group session and at the final session, infant fecal samples and mother's milk samples will be collected and tested for detectable levels of both probiotics to determine if horizontal transmission of the probiotic species occurred in the setting of a lactation support group.

Study Record Dates

• First Submitted: January 19, 2023
• First Posted: January 30, 2023
• Study Start: March 1, 2023
• Primary Completion: October 29, 2024
• Study Completion: April 9, 2025
• Last Updated: August 1, 2025

Record last verified: 2025-07

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)