F8 and hemorrhagic disease: The development of prenatal therapies able to provide FVIII levels that are curative, or sufficient to convert a severe, life-threatening bleeding disorder to a mild phenotype, while concomitantly inducing immune tolerance to the FVIII product, and thereby eliminating the risk of FVIII inhibitor formation, would have a major beneficial impact on the life expectancy and quality-of-life of HA patients, and it would transform the standard of care in HA treatment8,9.