Table 1.
Patient, disease and prior treatment characteristics
| Characteristic | Value |
|---|---|
| Females (N = 304), n (%) | 192 (63.2) |
| Age at baseline (N = 304), median (IQR) | 38.0 (29.0–45.5) |
| ≤ 40 years | 184 (60.5) |
| > 40 years | 120 (39.5) |
| Disease duration at baseline (N = 299), median (IQR) | 6.2 (3.1–10.7) |
| ≤ 5 years | 123 (41.1) |
| > 5 years | 176 (58.9) |
| Relapses in the year prior to natalizumab initiation (N = 304), n (%) | |
| ≤ 1 | 140 (46.1) |
| > 1 | 164 (53.9) |
| ARR in the year prior to natalizumab onset (95% CI), (N = 304) | 1.859 (1.708–2.023) |
| ARR in the 2 years prior to natalizumab onset (95% CI), (N = 304) | 1.355 (1.261–1.455) |
| Baseline EDSS score (N = 286), median (IQR) | |
| ≤ 3 points | 135 (47.2) |
| > 3 points | 151 (52.8) |
| Positive anti-JCV serostatus at baseline (N = 72), n (%)a | 28 (38.9) |
| Prior DMTs (N = 304), n (%) | |
| 0 | 37 (12.2) |
| ≥ 1 | 267 (87.8) |
| ≥ 2 | 128 (42.1) |
| Prior steroids/immunoglobulins (N = 304), n (%) | 148 (48.7) |
| Prior antineoplastic/immunosuppressive therapy (N = 304), n (%) | 20 (6.6) |
| Natalizumab treatment duration (N = 304), median (IQR), months | 58.7 (30.7–78.0) |
| Patients with permanent natalizumab treatment discontinuation (N = 304), n (%) | 154 (50.7) |
ARR annualized relapse rate, CI confidence interval, DMT disease-modifying therapy, EDSS Expanded Disability Status Scale, IQR interquartile range; JCV John Cunningham virus, N number of patients with available data
aAnti-JCV testing at baseline was not a prerequisite during the enrollment period of the study