The National Committee for Health Technology Incorporation (CONITEC) evaluates health technologies to recommend their inclusion or exclusion within the Brazilian Public Health System (SUS), and uses the budget impact assessment to estimate costs to the system. This study estimated the budget impact of the supply of methionine-free amino acid formula (MFAAf) for patients with classical homocystinuria (HCU) in the SUS.

The incidence of one case per 250,000 live births in Brazil and the registration of a Brazilian association of patients with HCU was assumed to calculate the population. Mortality and responsiveness to pyridoxine rates were applied. The costs of treatment were estimated according to the recommended dosage in literature and public purchasing prices. For calculating the dose of MFAAf patients, a median age of 19 years and weight of 60 kg were assumed, according to Brazilian study data.

The annual cost of treatment was estimated at BRL 77,000 (USD 21,084) per patient. The incorporation of MFAAf for HCU would generate a budget impact in SUS of around BRL 37 million (USD 10.1 million) in 2019 and BRL 188 million (USD 51.5 million) after five years which considers the epidemiological data, and a budget impact of around BRL 6.4 million (USD 1.75 million) in 2019 and BRL 33 million (USD 9 million) after five years which considers the information of a Brazilian association of patients with HCU. The wide range of values in the incremental budgetary impact is due to the lack of information on the epidemiology of the disease in Brazil.

The incorporation of the MFAAf in the SUS represents an important budgetary impact and covers a small number of patients. CONITEC recommended the incorporation of the MFAAf in the SUS, according to clinical protocol.