Characteristics of the 32 patients studied more than 1 year after stopping NTZ
| Characteristics | Patients with relapse | Relapse-free patients | p Value |
|---|---|---|---|
| Sex, F/M | 10/8 | 11/3 | ns |
| MS subtype, RR/SP | 15/3 | 11/3 | ns |
| Age, median (range) years | 40 (25–55) | 45 (27–57) | ns |
| Age at onset, median (range) years | 25 (12–45) | 31 (18–50) | ns |
| NTZ duration, median (range) months | 26 (12–55) | 31 (12–56) | ns |
| Alternative treatment after NTZ | ns | ||
| None | 6 | 2 | |
| Immunomodulator* | 2 | 4 | |
| Methylprednisolone† with/without immunomodulator | 10 | 8 | |
| Annualised relapse rate, mean±SD | ns | ||
| Before NTZ | 2.2±1.3 | 1.5±0.9 | |
| After NTZ | 1.8±0.8 | – | |
| EDSS score, mean±SD | ns | ||
| Before NTZ | 4.5±1.7 | 5.5±1.7 | |
| After NTZ | 4.7±1.9 | 5.7±2.2 | |
| Gadolinium-enhancing lesion(s), mean±SD | ‡ | ||
| Before NTZ | 2.2±3.7 | 2.4±3.0 | |
| After NTZ | 17.2±18.2 | 0.3±0.6 |
*After stopping NTZ, interferon-β or glatiramer acetate was started within 1 month or immediately, respectively.
†1 month after NTZ interruption, a 1-g methylprednisolone pulse was given monthly for 6 months.
‡The number of gadolinium-enhancing lesions before starting NTZ was comparable for the two groups. The number of gadolinium-enhancing lesions increased after NTZ interruption for patients with relapse (p=0.003) and decreased for relapse-free patients (p=0.03).
EDSS, Expanded Disability Status Scale; MS, multiple sclerosis; NTZ, natalizumab; RR, relapsing-remitting; SP, secondary progressive.