A new partially hydrolyzed whey-based follow-on formula with age-adapted protein content supports healthy growth during the first year of life

BACKGROUND: Standard infant formulae often have higher protein content than breastmilk in order to compensate for potentially lower digestibility; excess protein intake may promote adverse effects later in life. A new partially hydrolyzed whey-based (pHF-W) follow-on formula (FoF) with age-adapted protein content was evaluated for growth and gastrointestinal (GI) tolerance in healthy infants. METHODS: Formula-fed (FF) infants (n = 108) received standard pHF-W formula (1.9 g protein/100 kcal) from enrollment (age ≤ 30 days) until age 120 days followed by new pHF-W FoF (1.6 g protein/100 kcal) until 360 days. Weight gain velocity (WGV) (mean daily WG from enrollment to age 180 days) was compared to WHO growth standards and a breastfed (BF) reference group (n = 86) (non-inferiority margin –3 g/day). GI tolerance was assessed using a validated questionnaire (scale range 13−65). RESULTS: WGV in FF infants (mean ± SD 24.0 ± 4.4 g/day) was non-inferior to BF (23.7 ± 3.9 g/day) and WHO standards (all p ≤ 0.013). Weight-for-age, length-for-age, weight-for-length, and head circumference-for-age z-scores of FF infants were not significantly different from BF at any timepoint. Symptoms of GI intolerance were low (≤23) at all timepoints and similar between groups. CONCLUSION: A new pHF-W FoF with age-adapted protein content fed sequentially after standard pHF-W infant formula is safe, well-tolerated, and promotes a healthy growth pattern consistent with BF infants and WHO standards during the first year of life. CLINICAL TRIAL REGISTRATION: [https://clinicaltrials.gov/], identifier [NCT03276663].