Table 1.
Baseline Characteristics and PML Course
| S1P-RM (n = 20) | Natalizumab (n = 64) | p Value | |
| Baseline characteristics | |||
| Demographic data | |||
| Sex (female), n (%) | 17 (85) | 45 (70.3) | 0.192a |
| Age at PML onset, median (IQR25-75) | 52 (46.5–60) | 44 (38–47) | <0.001b |
| Characteristics of multiple sclerosis (MS) | |||
| Type of MS | 0.127a | ||
| Relapsing-remitting, n (%) | 17 (85) | 30/31 (96.8) | |
| Secondary progressive, n (%) | 3 (15) | 1/31 (3.2) | |
| Duration of MS before PML onset in months, median (IQR25-75) | 208.4 (164.2–261)c | 144 (84–200.4)d | 0.004b |
| MS activity under DMT in the past 2 years before PML, n (%) | 6 (30) | 4/21 (19) | 0.414a |
| Previous DMT before the one associated with PML | |||
| Previous immunomodulator treatment, n (%) | 19 (95.0) | 59 (92.2) | 0.670a |
| Previous immunosuppressor treatment, n (%) | 5 (25.0) | 15 (23.4) | 0.886a |
| Duration of the treatment associated with PML, median (IQR25-75) | 63.9 (46.3–85.9) | 40 (26.6–51)e | <0.001b |
| Baseline EDSS, median (IQR25-75) | 3 (1.6–5.5) | 3.5 (2–5.4)e | 0.503b |
| Baseline mRS, median (IQR25-75) | 1.5 (1–3) | 2 (1–3) | 0.975b |
Abbreviations: DMT = disease-modifying treatments; IQR = interquartile range; MS = multiple sclerosis; NTZ = natalizumab; S1PR-M = sphingosine-1-phosphate receptor modulators.
a
Asymptotic Pearson χ2.
b
Student t test.
c
One value is missing.
d
Three values are missing.
e
Four values are missing.