Representative monoclonal FVIII antibodies and their epitopes
| FVIII domain . | Name . | Species . | BU/mg IgG . | Type . | Isotype . | Group . | Epitope∗ . | Defined mechanism . |
|---|---|---|---|---|---|---|---|---|
| A2 | 4A4/GMA 8015 | Mouse | 40 000 | I | IgG2ak | A | Asp403-His444 | Inhibits intrinsic FXase formation |
| A2 | 2-76/GMA 8021 | Mouse | 38 000 | I | IgG2ak | A | Arg484-Ile508 (482-502) | |
| A2 | 413 | Mouse | 21 000 | I | IgG1k | A | Arg484-Ile508 | Inhibits FXa formation (blocks FIXa binding) |
| A2 | B157 | Mouse | <1 | N/A | IgG1k | AB | IND | |
| A2 | 2-93 | Mouse | 4 | II | IgG1k | B | Arg541-Glu604 | |
| A2 | 4F4/GMA 8017 | Mouse | 330 | I | IgG2ak | B | IND | |
| A2 | B99 | Mouse | 11 | I | IgG1k | BCD | IND | |
| A2 | G48 | Mouse | 5 | II | IgG2ak | C | His444-Arg541 | |
| A2 | 2-54 | Mouse | 34 000 | II | IgG1k | D | Glu604-Arg740 | Inhibits cleavage at R372 and R1689 |
| A2 | CLB-CAg9 | Mouse | IND | II | IgG1k | D | Glu604-Arg740 | Inhibits cleavage by FIIa at R740 and R1689 |
| A2 | GMA-012 | Mouse | <1 | N/A | IgG1k | D | Glu604-Arg740 | Inhibits cleavage by FIIa at R740, R1689 |
| A2 | 1D4/GMA 8009 | Mouse | 7 000 | I | IgG2ak | E | Glu604-Arg740 | Inhibits FXa formation and thrombin cleavage |
| A2 | R8B12 | Mouse | N/A | 497-510, 584-593 | Decreased FIXa binding by 20% | |||
| A2 | NB11B2 | Human | 67 000 | I | IgG4 | N/A | 379-456 | |
| A2 | VK34 | Human | 280 | I | scFv | N/A | Arg484-Ile508 | |
| A2 | VK41 | Human | <1 | N/A | scFv | N/A | Asp712-Ala736 | |
| A3 | KM41 | Human | 63 | N/A | scFv | N/A | Arg1803-Lys1818 | Inhibits intrinsic Xase formation |
| A3 | NB41 | Human | 830 | I | IgG4 | N/A | Arg1803-Lys1818 | Inhibits intrinsic Xase formation |
| A3 | NBA3 | Human | <1 | N/A | IgG4 | N/A | 1694-2017 | |
| B, A3, C1 | 2A9/GMA 8011 | Mouse | 23 | II | IgG2ak | A | Lys2065-Trp2070, Arg2150-Tyr2156, Lys2110-Trp2112 + Phe173-Tyr1748 (A3) + Asn1810 (B) | Blocks VWF binding |
| C1 | B153 | Mouse | 3 | II | IgG2ak | A | 2063-2071, 2129-2136 | Blocks VWF binding |
| C1 | KM33 | Human | 3 700 | I | IgG1k | AB | 2157-2164, 2091-2092 | Inhibits phospholipid and VWF binding |
| C1 | KM33 | Human | 97 | scFv | AB | Q1778-D1840 | scFv of KM33 | |
| C1 | NB33 | Human | 2 318 | I | IgG4 | AB | R2090-S2094, I2158-R2159 | Ig derivative of KM33 |
| C1 | B136 | Mouse | 700 | I | IgG2ak | B | 2077-2084 | Inhibit phospholipid and/or VWF binding |
| C1 | NB2E9 | Human | 121 708 | II | IgG4 | A | E2206, R2150 | |
| C1 | NBG12 | Human | 0 | N/A | IgG4 | N/A | 2077-2084 | |
| C2 | 3E6/GMA 8013 | Mouse | 41 | I | IgG2ak | A | Glu2181-Ala2188, Thr2202-Arg2215 | Inhibit phospholipid and/or VWF binding |
| C2 | ESH4 | Mouse | 39 | II | IgG2a | A | N/A | Inhibit phospholipid and/or VWF binding |
| C2 | I109 | Mouse | 1 500 | I | IgG1k | AB | Met2199-Phe2200 | Inhibit phospholipid and/or VWF binding |
| C2 | BO2C11 | Human | 20 000 | I | IgG4 | AB | 2199-2203, 2250-2253 | Inhibit phospholipid binding, competes with VWF for FVIII binding |
| C2 | 3D12 | Mouse | 2 600 | I | IgG2bk | B | Leu2251-Leu2252, Phe2196 | Inhibit phospholipid and/or VWF binding |
| C2 | G99/GMA 8026 | Mouse | 15 000 | II | IgG2ak | BC | Complex; centered around Lys2227 | Decreased FVIII activation by thrombin/FX |
| C2 | ESH8 | Mouse | 10 000 | II | IgG2a | C | 2248-2285 | Decreased FVIII activation by thrombin/FX |
| C2 | NMC-VIII/5 | Mouse | 81 | I | N/A | N/A | Glu2181-Val2243; Ser2173-Tyr2332 | |
| C2 | NB2C11 | Human | 8 869 | I | IgG4 | AB | F2196, N2198, M2199, F2200 + R2215, R2220 |
| FVIII domain . | Name . | Species . | BU/mg IgG . | Type . | Isotype . | Group . | Epitope∗ . | Defined mechanism . |
|---|---|---|---|---|---|---|---|---|
| A2 | 4A4/GMA 8015 | Mouse | 40 000 | I | IgG2ak | A | Asp403-His444 | Inhibits intrinsic FXase formation |
| A2 | 2-76/GMA 8021 | Mouse | 38 000 | I | IgG2ak | A | Arg484-Ile508 (482-502) | |
| A2 | 413 | Mouse | 21 000 | I | IgG1k | A | Arg484-Ile508 | Inhibits FXa formation (blocks FIXa binding) |
| A2 | B157 | Mouse | <1 | N/A | IgG1k | AB | IND | |
| A2 | 2-93 | Mouse | 4 | II | IgG1k | B | Arg541-Glu604 | |
| A2 | 4F4/GMA 8017 | Mouse | 330 | I | IgG2ak | B | IND | |
| A2 | B99 | Mouse | 11 | I | IgG1k | BCD | IND | |
| A2 | G48 | Mouse | 5 | II | IgG2ak | C | His444-Arg541 | |
| A2 | 2-54 | Mouse | 34 000 | II | IgG1k | D | Glu604-Arg740 | Inhibits cleavage at R372 and R1689 |
| A2 | CLB-CAg9 | Mouse | IND | II | IgG1k | D | Glu604-Arg740 | Inhibits cleavage by FIIa at R740 and R1689 |
| A2 | GMA-012 | Mouse | <1 | N/A | IgG1k | D | Glu604-Arg740 | Inhibits cleavage by FIIa at R740, R1689 |
| A2 | 1D4/GMA 8009 | Mouse | 7 000 | I | IgG2ak | E | Glu604-Arg740 | Inhibits FXa formation and thrombin cleavage |
| A2 | R8B12 | Mouse | N/A | 497-510, 584-593 | Decreased FIXa binding by 20% | |||
| A2 | NB11B2 | Human | 67 000 | I | IgG4 | N/A | 379-456 | |
| A2 | VK34 | Human | 280 | I | scFv | N/A | Arg484-Ile508 | |
| A2 | VK41 | Human | <1 | N/A | scFv | N/A | Asp712-Ala736 | |
| A3 | KM41 | Human | 63 | N/A | scFv | N/A | Arg1803-Lys1818 | Inhibits intrinsic Xase formation |
| A3 | NB41 | Human | 830 | I | IgG4 | N/A | Arg1803-Lys1818 | Inhibits intrinsic Xase formation |
| A3 | NBA3 | Human | <1 | N/A | IgG4 | N/A | 1694-2017 | |
| B, A3, C1 | 2A9/GMA 8011 | Mouse | 23 | II | IgG2ak | A | Lys2065-Trp2070, Arg2150-Tyr2156, Lys2110-Trp2112 + Phe173-Tyr1748 (A3) + Asn1810 (B) | Blocks VWF binding |
| C1 | B153 | Mouse | 3 | II | IgG2ak | A | 2063-2071, 2129-2136 | Blocks VWF binding |
| C1 | KM33 | Human | 3 700 | I | IgG1k | AB | 2157-2164, 2091-2092 | Inhibits phospholipid and VWF binding |
| C1 | KM33 | Human | 97 | scFv | AB | Q1778-D1840 | scFv of KM33 | |
| C1 | NB33 | Human | 2 318 | I | IgG4 | AB | R2090-S2094, I2158-R2159 | Ig derivative of KM33 |
| C1 | B136 | Mouse | 700 | I | IgG2ak | B | 2077-2084 | Inhibit phospholipid and/or VWF binding |
| C1 | NB2E9 | Human | 121 708 | II | IgG4 | A | E2206, R2150 | |
| C1 | NBG12 | Human | 0 | N/A | IgG4 | N/A | 2077-2084 | |
| C2 | 3E6/GMA 8013 | Mouse | 41 | I | IgG2ak | A | Glu2181-Ala2188, Thr2202-Arg2215 | Inhibit phospholipid and/or VWF binding |
| C2 | ESH4 | Mouse | 39 | II | IgG2a | A | N/A | Inhibit phospholipid and/or VWF binding |
| C2 | I109 | Mouse | 1 500 | I | IgG1k | AB | Met2199-Phe2200 | Inhibit phospholipid and/or VWF binding |
| C2 | BO2C11 | Human | 20 000 | I | IgG4 | AB | 2199-2203, 2250-2253 | Inhibit phospholipid binding, competes with VWF for FVIII binding |
| C2 | 3D12 | Mouse | 2 600 | I | IgG2bk | B | Leu2251-Leu2252, Phe2196 | Inhibit phospholipid and/or VWF binding |
| C2 | G99/GMA 8026 | Mouse | 15 000 | II | IgG2ak | BC | Complex; centered around Lys2227 | Decreased FVIII activation by thrombin/FX |
| C2 | ESH8 | Mouse | 10 000 | II | IgG2a | C | 2248-2285 | Decreased FVIII activation by thrombin/FX |
| C2 | NMC-VIII/5 | Mouse | 81 | I | N/A | N/A | Glu2181-Val2243; Ser2173-Tyr2332 | |
| C2 | NB2C11 | Human | 8 869 | I | IgG4 | AB | F2196, N2198, M2199, F2200 + R2215, R2220 |
References for antibodies are provided in supplemental Table 1, available on the Blood website. Bold font indicates human antibodies.
BU, Bethesda unit; GMA, green mountain antibody; IgG, immunoglobulin G; IND, indeterminate; N/A, not available.
Grouping as defined in previous studies by Healey et al,104 van den Brink et al,105 and Gilles et al.106