Iron Absorption From an Iron-fortified Follow-up Formula With Added Synbiotic or Human Milk Oligosaccharides

Study Overview
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Brief Summary
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The co-primary objectives of this study are: 1) to investigate the effect adding a synbiotic (combination of a pre-and probiotic) to iron-fortified follow-up formula (FUF) on iron bioavailability, and 2) to investigate the effect adding Human Milk Oligosaccharides (HMOs) to iron-fortified FUF on iron bioavailability in 10-14 month-old Thai children.

Detailed Description
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Iron stores of healthy, full-term neonates are supposed to cover iron needs for the first 4-6 months of life. After 6 months of age, requirements for absorbed iron are high, as infants need to build body iron stores and triple their body weight before the first year of life. Iron concentrations in mature breastmilk are low ( 0.3 mg/L) and cannot adequately cover the high iron requirements of children between 6 and 24 months of age. Follow-up formulas (FUF) are fortified milk-based products intended for infants above 6 months of age and young children aged 1-3 years, and are widely used as a liquid part of the weaning diet to supplement the diet of young children with macro- and micronutrients. Prebiotics and probiotics are increasingly added to foods for infants and young children due to emerging evidence on possible health benefits. We recently showed that the addition of prebiotic galacto-oligosaccharides (GOS) to an iron-containing micronutrient powder increased iron absorption in Kenyan infants. To our knowledge, the effect of the combination of pre- and probiotics (synbiotic) or human milk oligosaccharides (HMOs) on iron absorption from an iron-fortified FUF has not been investigated. Thai children (10-14 months old) will be assigned to receive FUF fortified with isotopically labelled iron as FeSO4 1) with synbiotic, 2) HMO, and 3) without added prebiotics as a reference, in random order. Besides the iron source and synbiotic or HMO, the test FUF will be identical in terms of macro- and micronutrient composition. For the secondary objectives of this study, which will have a single-group, before-after design, each infant will receive the test FUF with added synbiotic for 25 days on gut comfort and quality of life outcomes.

Official Title
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Iron Absorption From an Iron-fortified Follow-up Formula With and Without the Addition of a Synbiotic or Human Milk Oligosaccharides: a Stable Isotope Study in 10-14 Month-old Thai Children

Conditions
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Iron Absorption

Intervention / Treatment
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* Other: Test formula A without added pre- and pro-biotic
* Other: Test formula B with synbiotic
* Other: Test formula C with HMOs


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Written informed consent has been obtained from the parents/legally acceptable representative Child aged 40-56 weeks (± 3 weeks) Child exhibits no clinical signs/symptoms of chronic disease or acute illness Capillary Hb ≥70 g/L Anticipated residence in the area for the study duration Z-scores for weight-for-age and weight-for-length both >-3, if the infant is severely underweight or severely malnourished. Singleton, full-term gestation birth (≥37 weeks) Birth weight ≥2.5 kg and ≤4.5 kg Exclusion Criteria: Child exhibits clinical signs/symptoms of chronic infectious, metabolic, genetic illness or other disease including any condition that impacts feeding or growth Child received vitamin and mineral supplements in the 2 weeks prior to enrollment Child is exclusively breastfed Child received antibiotic treatments in the 4 weeks prior to enrollment Parents or caretakers not willing/not able to comply with the requirements of the study protocol Child has allergy or intolerance to cows' milk protein or lactose, or severe food allergies Child is participating in any other interventional clinical trial that would interfere with study outcomes

Ages Eligible for Study
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Minimum Age: 40 Weeks
Maximum Age: 56 Weeks

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Test formula C<br> | Other: Test formula C with HMOs<br>* Test formula fortified with 2.20 mg iron as FeSO4-54 and 0.05 mg native iron per serving (235 ml) and added HMOs.<br>|
| Experimental: Test formula B<br> | Other: Test formula B with synbiotic<br>* Test formula fortified with 2.20 mg iron as FeSO4-57 and 0.05 mg native iron per serving (235 ml) and added synbiotic.<br>|
| Placebo Comparator: Test formula A<br> | Other: Test formula A without added pre- and pro-biotic<br>* An identical formula as test formulas fortified with 2.20 mg iron as FeSO4-58 and 0.05 mg native iron per serving (235 ml), but without added pre- or probiotic.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fractional Iron Absorption (FIA) from an iron-fortified follow-up infant formula with and without the addition of a synbiotic | FIA from test formulas will be determined based on the shift of the iron isotope ratios in whole blood. | Measured 28 days after administration of last test formula | 
| Fractional Iron Absorption (FIA) from an iron-fortified follow-up infant formula with and without the addition of a synbiotic | FIA from test formulas will be determined based on the shift of the iron isotope ratios in whole blood. | Measured 14 days after administration of last test formula | 
| FIA from an iron-fortified follow-up formula with and without the addition of human oligosaccharides (HMOs) | FIA from test formulas will be determined based on the shift of the iron isotope ratios in whole blood. | Measured 28 days after administration of last test formula | 
| FIA from an iron-fortified follow-up formula with and without the addition of human oligosaccharides (HMOs) | FIA from test formulas will be determined based on the shift of the iron isotope ratios in whole blood. | Measured 14 days after administration of last test formula | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Effects of feeding an iron-fortified FUF with added synbiotic (Formula B) for 25 days on Iron status (haemoglobin [Hb]) | Change in iron status biomarkers (Hb) from baseline until last study visit (day 40) | At baseline and last study visit (day 40) | 
| Effects of feeding an iron-fortified FUF with added synbiotic (Formula B) for 25 days on Iron status (plasma ferritin [PF]) | Change in iron status biomarkers (PF) from baseline until last study visit (day 40) | At baseline and last study visit (day 40) | 
| Effects of feeding an iron-fortified FUF with added synbiotic (Formula B) for 25 days on Iron status (soluble transferrin receptor [sTfR]) | Change in iron status biomarkers (sTfR) from baseline until last study visit (day 40) | At baseline and last study visit (day 40) | 
| Effects of feeding an iron-fortified FUF with added synbiotic (Formula B) for 25 days on inflammation status ((C-reactive protein [CRP]) | Change in CRP from baseline until last study visit (day 40) | At baseline and last study visit (day 40) | 
| Effects of feeding an iron-fortified FUF with added synbiotic (Formula B) for 25 days on inflammation status (alpha-1-acid glycoprotein [AGP])) | Change in AGP from baseline until last study visit (day 40) | At baseline and last study visit (day 40) | 
| Effects of feeding an iron-fortified FUF with added synbiotic (Formula B) for 25 days on gastrointestinal (GI) tolerance | Change in GI tolerance based on caregiver-reported stool frequency (number of stools per day), consistency (on a scale from watery, runny, mushy soft, formed soft, hard, and difficult-to-pass stools (yes/no) from baseline until last study visit (day 40) | At baseline and last study visit (day 40) | 
| Effects of feeding an iron-fortified FUF with added synbiotic (Formula B) for 25 days on gut comfort | Change in gut comfort based on Gut Comfort Questionnaire to assess overall GI burden and individual GI symptoms/GI-related behaviours from baseline until last study visit (day 40) | At baseline and last study visit (day 40) | 
| Effects of feeding an iron-fortified FUF with added synbiotic (Formula B) for 25 days on health-related quality of life | Change in health-related quality of life, assessed by validated Infant and Toddler Quality of Life questionnaire from baseline until last study visit (day 40) | At baseline and last study visit (day 40) | 
| Effect of feeding an iron-fortified FUF with added synbiotic (Formula B) for 25 days on gut microbiota composition and diversity | Change in gut microbiota composition and diversity between baseline and last study visit (day 40) | At baseline and last study visit (day 40) | 
| Effect of feeding an iron-fortified FUF with added synbiotic (Formula B) for 25 days on fecal pH | Change in fecal pH between baseline and last study visit (day 40) | At baseline and last study visit (day 40) | 
| Effect of feeding an iron-fortified FUF with added synbiotic (Formula B) for 25 days on gut inflammation | Change in gut inflammation marker (calprotectin) between baseline and last study visit (day 40) | At baseline and last study visit (day 40) | 
| Effect of feeding an iron-fortified FUF with added synbiotic (Formula B) for 25 days on gut integrity | Change in gut integrity marker (serum intestinal fatty acid binding protein [I-FABP]) between baseline and last study visit (day 40) | At baseline and last study visit (day 40) |