Prebiotic‐supplemented partially hydrolysed cow's milk formula for the prevention of eczema in high‐risk infants: a randomized controlled trial

BACKGROUND: Prevention guidelines for infants at high risk of allergic disease recommend hydrolysed formula if formula is introduced before 6 months, but evidence is mixed. Adding specific oligosaccharides may improve outcomes. OBJECTIVE: To evaluate whether partially hydrolysed whey formula containing oligosaccharides (0.8 g/100 ml) (pHF‐OS) can prevent eczema in high‐risk infants [ISRCTN65195597]. METHODS: We conducted a parallel‐group, multicentre, randomized double‐blind controlled trial of pHF‐OS vs standard cow's milk formula. Infants with a family history of allergic disease were randomized (stratified by centre/maternal allergy) to active (n = 432) or control (n = 431) formula until 6 months of age if formula was introduced before 18 weeks. Primary outcome was cumulative incidence of eczema by 12 months in infants randomized at 0–4 weeks (375 pHF‐OS, 383 control). Secondary outcomes were cumulative incidence of eczema by 12 or 18 months in all infants randomized, immune markers at 6 months and adverse events. RESULTS: Eczema occurred by 12 months in 84/293 (28.7%) infants allocated to pHF‐OS at 0‐4 weeks of age, vs 93/324 (28.7%) control (OR 0.98 95% CI 0.68, 1.40; P = 0.90), and 107/347 (30.8%) pHF‐OS vs 112/370 (30.3%) control in all infants randomized (OR 0.99 95% CI 0.71, 1.37; P = 0.94). pHF‐OS did not change most immune markers including total/specific IgE; however, pHF‐OS reduced cow's milk‐specific IgG1 (P < 0.0001) and increased regulatory T‐cell and plasmacytoid dendritic cell percentages. There was no group difference in adverse events. CONCLUSION: pHF‐OS does not prevent eczema in the first year in high‐risk infants. The immunological changes found require confirmation in a separate cohort.