Table 2.
Median (95% CI) time to ADAMTS13 activity ≥ 10%, ≥ 20%, and ≥ 60% overall and according to different clinical characteristics
| Overall/Clinical characteristic | Number of patients | Time to sustained ADAMTS13 activity ≥ 10%, median (95% CI), days | Time to sustained ADAMTS13 activity ≥ 20%, median (95% CI), days | Time to sustained ADAMTS13 activity ≥ 60%, median (95% CI), days |
|---|---|---|---|---|
| Overall | 19 | 14.6 (5.9–24.8) | 18.5 (5.9–31.8) | 47.5 (18.5–60.9) |
| Concomitant rituximab | ||||
| No rituximab used | 6 | 6.3 (4.7–NC) | 6.4 (4.7–NC) | 23.9 (6.9–NC) |
| Rituximab used | 13 | 24.8 (6.9–38.8) | 31.8 (13.7–38.8) | 49.8 (13.7–61.9) |
| Baseline ADAMTS13 inhibitor | ||||
| < 2 BU/mL | 12 | 14.1 (4.5–24.8) | 16.1 (4.5–31.8) | 23.2 (6.9–51.8) |
| ≥ 2 BU/mL | 7 | 33.5 (4.7–NC) | 33.5 (4.7–NC) | 54.7 (18.8–NC) |
| Time since iTTP diagnosis | ||||
| ≤ 5 days | 13 | 18.5 (5.9–37.8) | 28.8 (5.9–37.8) | 37.7 (17.6–61.9) |
| > 5 days | 6 | 10.3 (4.4–NC) | 14.1 (4.4–NC) | 39.8 (4.5–NC) |
| Disease severity at baseline | ||||
| Less severe | 8 | 10.8 (4.7–46.9) | 17.7 (4.7–53.9) | 60.9 (6.9–NC) |
| Very severe | 11 | 17.6 (4.5–24.8) | 18.5 (4.5–31.8) | 19.9 (13.7–49.8) |
| Platelet count at baseline | ||||
| < 20*109/L | 9 | 18.5 (5.9–37.8) | 28.8 (5.9–37.8) | 33.7 (6.9–NC) |
| ≥ 20*109/L | 9 | 13.7 (4.5–46.9) | 14.6 (4.5–53.9) | 49.8 (4.5–61.9) |
| Inhibitor boosting present | ||||
| No | 10 | 6.4 (4.4–13.7) | 6.4 (4.4–14.6) | 18.7 (4.5–27.8) |
| Yes | 9 | 35.7 (6.7–46.9) | 35.7 (18.5–53.9) | 56.4 (18.5–NC) |
| Previous iTTP episode | ||||
| No | 14 | 18.5 (5.9–37.8) | 28.8 (5.9–37.8) | 47.5 (18.5–60.9) |
| Yes | 5 | 6.9 (4.4–NC) | 13.7 (4.4–NC) | 18.6 (4.5–NC) |
ADAMTS13, a disintegrin and metalloproteinase with thrombospondin type 1 motif member 13; CI, confidence interval; iTTP, immune-mediated thrombotic thrombocytopenic purpura; NC, not calculated