We investigated the role of ABO blood groups in regulating FVIII immunogenicity by evaluating their distribution in patients with severe (FVIII < 1 IU/dL) HA according to inhibitor development and other known relevant factors.
In non-carriers, the association of FVIII with ABO blood groups was statistically significant (P = 0.006), but not in carriers of haemophilia A (P = 0.234).