TABLE 2.
Cumulative aducanumab safety data: PC period and LTE after first aducanumab dose.
| Safety population | 1 to 3 mg/kg (n = 31) | 3 mg/kg (n = 42) | 6 mg/kg (n = 30) | 10 mg/kg (n = 32) | Titration, 3 to 6 mg/kg (n = 19) | Titration, 1to 3 to 6 to 10 mg/kg (n = 31) | All aducanumab dose groups combined (n = 185) |
|---|---|---|---|---|---|---|---|
| No. of weeks on study treatment, mean (±SD) | 123 (105) | 158 (120) | 165 (98) | 120 (113) | 146 (87) | 155 (72) | 145 (103) |
| AEs, n (%) | 29 (94) | 39 (93) | 30 (100) | 29 (91) | 19 (100) | 31 (100) | 177 (96) |
| SAEs, n (%) | 11 (35) | 19 (45) | 14 (47) | 16 (50) | 12 (63) | 12 (39) | 84 (45) |
| Fatal AEs, n (%) a | 1 (3) | 1 (2) | 1 (3) | 2 (6) | 1 (5) | 0 | 6 (3) |
| AEs leading to discontinuation of treatment, n (%) | 4 (13) | 9 (21) | 5 (17) | 16 (50) | 6 (32) | 3 (10) | 43 (23) |
| Safety MRI population | 1 to 3 mg/kg (n = 31) | 3 mg/kg (n = 42) | 6 mg/kg (n = 30) | 10 mg/kg (n = 32) | Titration, 3 to 6 mg/kg (n = 19) | Titration, 1to 3 to 6 to 10 mg/kg (n = 31) | All aducanumab dose groups combined (n = 185) |
|---|---|---|---|---|---|---|---|
| ARIA‐E, n/total (%) | 4/31 (13) | 5/42 (12) | 11/30 (37) | 13/32 (41) | 3/19 (16) | 10/31 (32) | 46/185 (25) |
| APOE ε4 carriers | 4/19 (21) | 3/25 (12) | 9/21 (43) | 11/20 (55) | 3/13 (23) | 10/31 (32) | 40/129 (31) |
| APOE ε4 homozygote | 0/1 | 1/5 (20) | 2/4 (50) | 3/6 (50) | 1/3 (33) | 2/4 (50) | 9/23 (39) |
| APOE ε4 heterozygote | 4/18 (22) | 2/20 (10) | 7/17 (41) | 8/14 (57) | 2/10 (20) | 8/27 (30) | 31/106 (29) |
| APOE ε4 noncarriers | 0/12 (0) | 2/17 (12) | 2/9 (22) | 2/12 (17) | 0/6 (0) | — | 6/56 (11) |
| In participants with ARIA‐E, n/total (%) | |||||||
| Asymptomatic | 2/4 (50) | 2/5 (40) | 7/11 (64) | 8/13 (62) | 1/3 (33) | 8/10 (80) | 28/46 (61) |
| Symptomatic | 2/4 (50) | 3/5 (60) | 4/11 (36) | 5/13 (38) | 2/3 (67) | 2/10 (20) | 18/46 (39) |
| ARIA‐E, discontinued treatment, n/total (%) | 1/31 (3) | 2/42 (5) | 3/30 (10) | 9/32 (28) | 3/19 (16) | 2/31 (6) | 20/185 (11) |
| Brain microhemorrhage | 2/31 (6) | 10/42 (24) | 8/30 (27) | 7/32 (22) | 4/19 (21) | 5/31 (16) | 36/185 (19) |
| Localized superficial siderosis | 2/31 (6) | 1/42 (2) | 3/30 (10) | 4/32 (13) | 0/19 | 4/31 (13) | 14/185 (8) |
Notes: Columns reflect patient aducanumab dose assignment while on active treatment. The treatment assignment of 1to 3 mg/kg represents an assignment to 1 mg/kg in the PC period and 3 mg/kg in the LTE.
Abbreviations: AE, adverse event; APOE ε4, apolipoprotein E ε4; ARIA, amyloid‐related imaging abnormalities; LTE, long‐term extension; MRI, magnetic resonance imaging; PC, placebo controlled; SAE, serious adverse event; SD, standard deviation.
a
Two additional deaths in participants who received placebo.