Table 2.
Treatment patterns of the overall eculizumab user and of eculizumab users stratified by blood transfusion dependence status
| Treatment patterns | Overall eculizumab user cohort | TD cohort | TF cohort |
|---|---|---|---|
| N = 151 | N = 55 | N = 96 | |
| Observation period,a years, mean ± SD [median] | 1.6 ± 1.3 [1.2] | 1.6 ± 1.3 [1.4] | 1.6 ± 1.4 [1.1] |
| Eculizumab infusionsb | |||
| Number of eculizumab infusions, median (IQR) | |||
| Overall | 11.0 (5.0–34.0) | 9.0 (5.0–29.0) | 11.5 (6.5–34.5) |
| Induction phasec | 4.0 (2.0–4.0) | 4.0 (2.0–4.0) | 4.0 (2.0–4.0) |
| Maintenance phased | 8.0 (3.0–30.0) | 5.0 (2.0–24.0) | 8.0 (3.0–32.0) |
| Time between eculizumab infusions, days, median (IQR)e | |||
| Overall | 13.7 (11.2–19.4) | 13.6 (9.9–19.4) | 13.8 (11.7–19.2) |
| Induction phasec | 7.0 (7.0–8.3) | 7.0 (7.0–8.6) | 7.0 (7.0–8.3) |
| Maintenance phased | 14.4 (13.7–21.2) | 14.5 (13.4–21.9) | 14.4 (13.7–20.5) |
| Average time between infusions during maintenance phase, n (%) | |||
| < 14 days | 30 (21.9) | 13 (27.7) | 17 (18.9) |
| 14 days | 40 (29.2) | 10 (21.3) | 30 (33.3) |
| 15–21 days | 34 (24.8) | 11 (23.4) | 23 (25.6) |
| > 21 days | 33 (24.1) | 13 (27.7) | 20 (22.2) |
| Patients with eculizumab discontinuatione, n (%) | 92 (60.9) | 36 (65.5) | 56 (58.3) |
| Duration of eculizumab treatment until discontinuation, days, mean ± SD [median]f | 204.5 ± 275.0 [87.5] | 154.9 ± 234.6 [87.0] | 236.4 ± 295.7 [87.5] |
| Time to discontinuation using Kaplan–Meier analysis, years, median | 0.7 | 0.5 | 0.9 |
| Blood transfusions | |||
| Number of blood transfusions, mean (min, max) | 3.1 (0.0, 54.0) | 8.5 (1.0, 54.0) | – |
| Patients with ≥ 1 blood transfusion during follow-up period, n (%) | 55 (36.4) | 55 (100.0) | 0 (0.0) |
| Iron chelation therapy | |||
| Number of iron chelation therapy, mean (min, max) | 0.2 (0.0, 11.0) | 0.5 (0.0, 11.0) | – |
| Patients with ≥ 1 iron chelation therapy during follow-up period, n (%) | 4 (2.6) | 4 (7.3) | 0 (0.0) |
IQR interquartile range, SD standard deviation
aDefined as the period from index date (i.e., date of first eculizumab infusion) to the earliest of end of continuous healthcare plan enrollment or end of data availability (September 30, 2019)
bEculizumab was identified using the HCPCS procedure code J1300
cThe induction phase was defined as the first 4 weeks of eculizumab treatment
dThe maintenance phase was defined as the fifth week of eculizumab treatment and onwards
eDiscontinuation was defined as a gap of more than 42 days between infusions or the last infusion and the end of follow-up (i.e., the earliest of end of continuous healthcare plan enrollment or end of data availability)
fDuration of treatment was calculated among the subset of patients discontinuing treatment