Cost-effectiveness Analysis of Hypoallergenic Milk Formulas for the Management of Cow’s Milk Protein Allergy in the United Kingdom

Background: Cow’s milk protein allergy (CMPA) is the most common food allergy in early childhood. In most children CMPA resolves by age 5 or 6; however, if not treated correctly can provoke nutritional deficiency resulting in poor growth. Management consists of excluding cow’s milk from the diet, with hypoallergenic formulas (or non-dairy alternatives) being introduced to meet nutritional requirements. Objectives: To compare the cost-effectiveness of hypoallergenic formulas in reducing allergic manifestations and promoting immune tolerance in infants with immunoglobulin E (IgE)-mediated symptoms of CMPA. Methods: A trial-based decision analytic cohort model was developed to simulate the occurrence of urticaria, eczema, asthma, rhinoconjunctivitis, or being symptom-free in infants with CMPA in the United Kingdom. Amino acid-based formula (AAF), extensively hydrolysed casein formula containing Lactobacillus rhamnosus Gorbach Goldin (EHCF+LGG), extensively hydrolysed whey formula (EHWF), and soy formula (SF) were compared using the National Health Service (NHS) perspective, 3-year time horizon and 3.5% discount rate for cost and health consequences. Hypoallergenic formulas comparative efficacy was sourced from a prospective cohort study. Resources required to manage allergic symptoms were sourced from published literature, validated by a UK clinician, and applied to UK cost resources. Results were reported as cost per additional child free from allergic manifestations at 3 years and cost per additional immune tolerant child at 3 years. Results: In the base case, infants receiving EHCF+LGG were associated with lower NHS resource use and improved CMPA tolerance. Over the 3-year treatment period, savings of £119, £476, and £2645 were achieved with EHCF+LGG compared to SF, EHWF and AAF, respectively. Infant formula accounted for the largest proportion of resource consumption averaging 47% for all comparators, with a minimum of 31% for SF and a maximum of 69% for AAF over 3 years. General practitioners’ visits constituted the second highest cost component, approximately 16% of total costs across comparators. The results were robust to deterministic and probabilistic sensitivity analyses. Conclusions: Compared to AAF, SF, and EHWF hypoallergenic formulas, EHCF+LGG was the most cost-effective, associated with lower total costs and contributing to a higher proportion of children being symptom-free and developing immune tolerance 3-years after diagnosis.