Dietary supplementation with Bifidobacterium longum subsp. infantis (B. infantis) in healthy breastfed infants: study protocol for a randomised controlled trial

Trials. 2016 Jul 22;17(1):340. doi: 10.1186/s13063-016-1467-1.


Background: The development of probiotics as therapies to cure or prevent disease lags far behind that of other investigational medications. Rigorously designed phase I clinical trials are nearly non-existent in the field of probiotic research, which is a contributing factor to this disparity. As a consequence, how to appropriately dose probiotics to study their efficacy is unknown. Herein we propose a novel phase I ascending dose trial of Bifidobacterium longum subsp. infantis (B. infantis) to identify the dose required to produce predominant gut colonisation in healthy breastfed infants at 6 weeks of age.

Methods/design: This is a parallel-group, placebo-controlled, randomised, double-blind ascending dose phase I clinical trial of dietary supplementation with B. infantis in healthy breastfed infants. The objective is to determine the pharmacologically effective dose (ED) of B. infantis required to produce predominant (>50 %) gut colonisation in breastfed infants at 6 weeks of age. Successively enrolled infant groups will be randomised to receive two doses of either B. infantis or placebo on days 7 and 14 of life. Stool samples will be used to characterise the gut microbiota at increasing doses of B. infantis.

Discussion: Probiotic supplementation has shown promising results for the treatment of a variety of ailments, but evidence-based dosing regimes are currently lacking. The ultimate goal of this trial is to establish a recommended starting dose of B. infantis for further efficacy-testing phase II trials designed to evaluate B. infantis for the prevention of atopic dermatitis and food allergies in at-risk children.

Trial registration: # NCT02286999 , date of trial registration 23 October 2014.

Keywords: Atopic dermatitis; Atopy; Bifidobacterium infantis; Dose-escalation; Food allergy; Phase I clinical trial; Probiotic.

Publication types

  • Clinical Trial, Phase I
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Factors
  • Bifidobacterium longum subspecies infantis / growth & development*
  • Breast Feeding*
  • California
  • Clinical Protocols
  • Double-Blind Method
  • Feces / microbiology
  • Female
  • Gastrointestinal Microbiome*
  • Gastrointestinal Tract / microbiology*
  • Humans
  • Infant
  • Infant, Newborn
  • Male
  • Probiotics / adverse effects
  • Probiotics / therapeutic use*
  • Research Design
  • Time Factors
  • Treatment Outcome

Associated data