(LB04-01-26) Growth and Safety of Infant Formula Made With Milk Free From A1 Beta-Casein: A Randomized, Double-Blind, Controlled Trial in Term Infants

Objectives: To compare growth and safety outcomes between full-term infants fed infant formula made from milk free from A1 beta-casein and those fed formula made from conventional milk. The study was conducted in line with US FDA guidelines specifying that new infant formulas must be tested to ensure they support normal physical growth (e.g., are non-inferior to a commercially available formula).

Methods: Randomized, controlled, double-blind trial enrolling healthy infants aged < 14 days. Infants were fed either formula made with milk free from A1 beta-casein protein (A1PF) or a commercially available FDA-approved conventional formula ad libitum. Growth and safety outcomes were collected at baseline and 16 weeks and compared between formula groups.

Results: A total of 156 infants were enrolled; 74 received A1PF formula and 75 received conventional formula (safety analysis set). Missing data were not imputed, so growth analyses included 61–67 participants per group. Age at baseline was similar between groups and there was an even split between male and female infants in each group. Between baseline and week 16, the mean (SD) overall weight gain was 3577.78 (660.11) g in the A1PF group and 3376.50 (645.30) g in the conventional group; overall length gain was 12.88 (2.31) cm and 12.08 (2.47) cm in the A1PF and conventional groups, respectively. The pre-defined non-inferiority criteria were met. Interestingly, after adjusting for baseline measurements, the mean (SD) length at week 16 was significantly greater in the A1PF group (63.41 [1.78] cm) than in the conventional group (62.83 [2.01] cm; 95% CI 0.10, 1.21, p = 0.021). Mean (SD) weight-for-age z-scores and length-for-age z-scores were also significantly higher in the A1PF group vs the conventional group (95% CI 0.05, 0.20, p = 0.001 and 95% CI 0.03, 0.20, p = 0.011, respectively). The observed growth differences were not explained by differences in intake. There were no significant between-group differences in the occurrences of AEs.

Conclusions: Infants consuming A1PF formula from < 14 days post-birth had appropriate growth through 16 weeks, meeting pre-defined non-inferiority criteria. Additional analyses reflected improved growth in terms of length and weight, compared with infants consuming a commercially available conventional formula, warranting further investigation.

Funding Sources: The a2 Milk Company