The potential economic value of a therapeutic Chagas disease vaccine for pregnant women to prevent congenital transmission

BackgroundCurrently, there are no solutions to prevent congenital transmission of Chagas disease during pregnancy, which affects 1–40% of pregnant women in Latin America and is associated with a 5% transmission risk. With therapeutic vaccines under development, now is the right time to determine the economic value of such a vaccine to prevent congenital transmission.MethodsWe developed a computational decision model that represented the clinical outcomes and diagnostic testing strategies for an infant born to a Chagas-positive woman in Mexico and evaluated the impact of vaccination.ResultsCompared to no vaccination, a 25% efficacious vaccine averted 125 95% uncertainty interval (UI): 122–128] congenital cases, 1.9 (95% UI: 1.6–2.2) infant deaths, and 78 (95% UI: 66–91) DALYs per 10,000 infected pregnant women; a 50% efficacious vaccine averted 251 (95% UI: 248–254) cases, 3.8 (95% UI: 3.6–4.2) deaths, and 160 (95% UI: 148–171) DALYs; and a 75% efficacious vaccine averted 376 (95% UI: 374–378) cases, 5.8 (95% UI: 5.5–6.1) deaths, and 238 (95% UI: 227–249) DALYs. A 25% efficacious vaccine was cost-effective (incremental cost-effectiveness ratio <3× Mexico’s gross domestic product per capita, <$29,698/DALY averted) when the vaccine cost ≤$240 and ≤$310 and cost-saving when ≤$10 and ≤$80 from the third-party payer and societal perspectives, respectively. A 50% efficacious vaccine was cost-effective when costing ≤$490 and ≤$615 and cost-saving when ≤$25 and ≤$160, from the third-party payer and societal perspectives, respectively. A 75% efficacious vaccine was cost-effective when ≤$720 and ≤$930 and cost-saving when ≤$40 and ≤$250 from the third-party payer and societal perspectives, respectively. Additionally, 13–42 fewer infants progressed to chronic disease, saving $0.41-$1.21 million to society.ConclusionWe delineated the thresholds at which therapeutic vaccination of Chagas-positive pregnant women would be cost-effective and cost-saving, providing economic guidance for decision-makers to consider when developing and bringing such a vaccine to market.