https://orcid.org/0009-0004-7630-9992
Key Points
Despite its high price, subcutaneous emicizumab prophylaxis is the cost-effective strategy for infants with severe hemophilia A.
Cost-effectiveness is achieved due to reduction of ICH incidence and its sequela with emicizumab prophylaxis in the first year of life.
Intracranial hemorrhage (ICH) and resulting neurological disability are severe complications for a subset of infants with severe hemophilia A (HA). While prophylactic factor replacement reduces bleeding risk, it is typically delayed until after age 1 due to risks associated with central venous access placement. Emicizumab, a subcutaneous activated factor VIII (FVIII) mimetic, has demonstrated safety and efficacy in preventing ICH in infants under 12 months in the HAVEN 7 trial. Despite its high cost the cost-effectiveness of emicizumab prophylaxis initiated during the first year of life for infants with severe HA is not known. We developed a Markov cohort model to compare emicizumab prophylaxis to standard care (no prophylaxis) in infants aged 0-1 year with severe HA without FVIII inhibitors. The analysis was conducted from a US societal perspective over a lifetime time horizon across all accepted willingness-to-pay (WTP) thresholds. The primary outcome was the incremental cost-effectiveness ratio (ICER) in USD per quality-adjusted life-year (QALY). Emicizumab prophylaxis and standard care accrued 25.6 and 25.1 QALYs at costs of $13.12 and $13.07 million, respectively, resulting in an ICER of $99,900/QALY (95% credible interval 84,000-120,000). Scenario analysis examining prophylaxis with low-dose emicizumab resulted in an ICER of $19,600/QALY (95% CI 12,000-29,000). Probabilistic sensitivity analyses showed that standard-dose emicizumab is the cost-effective strategy in 100%, 66%, and 0% of 10,000 Monte Carlo iterations at WTP thresholds of $150,000, $104,000, and $50,000/QALY, respectively, and in 100% across all WTP thresholds for low-dose emicizumab.
