Table 2.

Patient characteristics stratified in 4 subgroups with distinct signatures of FVIII-binding antibodies developed during the HIPS study

Patient no.	F8 mutation	Age at first FVIII infusion, mo	Peak FVIII inhibitor titer, BU/mL	First FVIII inhibitor detection	Ethnic background	Family history of hemophilia A	Family history of FVIII inhibitors
Subgroup 1: no FVIII-binding IgG antibodies
1	Missense	9.1	<0.4	NA	White	No	No
2	Intron 22 inversion	12.7	<0.4	NA	White	Yes	Yes
3	Missense	2.8	<0.4	NA	White	Yes	No
4	Missense	2.5	<0.4	NA	Black	Yes	No
5	Duplication	7.8	<0.4	NA	White	No	No
6	Frameshift	16.6	<0.4	NA	White	Yes	Yes
7	Nonsense	6.7	<0.4	NA	White	Yes	Unknown
Subgroup 2: non-neutralizing FVIII-binding antibodies
8	Intron 22 inversion	9.3	<0.4	NA	White	No	No
9	Missense	19.9	<0.4	NA	Black	Yes	Yes
10	Intron 22 inversion	3.6	<0.4	NA	White	No	No
11	Missense	13.5	<0.4	NA	White	No	No
12	Intron 1 inversion	12.0	<0.4	NA	White	No	No
13	Missense	10.7	<0.4	NA	White	No	No
14	Intron 22 inversion	0.4	<0.4	NA	White	Yes	Yes
Subgroup 3: transient FVIII inhibitors
15	Frameshift	14.7	1.8	ED20	Black	Yes	Yes
16	Intron 22 inversion	9.7	1.4	ED12	White	Yes	No
Subgroup 4: persistent FVIII inhibitors
17	Large deletion	10.2	4.5	ED20	Hispanic	No	No
18	Large deletion	12.0	7	ED6	Hispanic	Yes	Unknown
19	Intron 22 inversion	12.6	796	ED10	White	Yes	Unknown
20	Duplication	12.0	9.5	ED10	Hispanic	Yes	Yes
21	Intron 22 inversion	10.3	323	ED10	White	Yes	Unknown
22	Intron 22 inversion	6.3	3049	ED10	Asian or Pacific	Yes	No
23	Intron 22 inversion	9.2	124	ED11	White	Yes	Yes

NA, not applicable.