Table 4.

Subgroup of patients with new enhancing lesions (months 1 to 6): Proportion of patients developing hypointense T1 lesions and proportion of enhancing lesions becoming hypointense in patients with at least 1 scan during months 19 to 24

Subgroup of patients with new enhancing lesions, months 1 to 6Placebo, n = 38IFNβ-1b, n = 28Absolute difference
* Thirty-seven patients (27 placebo/10 IFNβ-1b) developed at least 1 large and at least 1 small enhancing lesion.
IFNβ-1b = interferon β-1b.
Proportion of patients developing hypointense T1 lesions
    All patients with enhancing lesions26 /38 (68.4%)12 /28 (42.9%)−25.5%
    Patients with small new enhancing lesions only2 /8 (25.0%)3 /13 (23.1%)−1.9%
    Patients with at least one large new enhancing lesion*24 /30 (80.0%)9 /15 (60.0%)−20.0%
Proportion of patients developing hypointense T1 lesions from large enhancing lesions
    Patients with at least one large new enhancing lesion*18 /30 (60.0%)7 /15 (46.7%)−13.3%
Cumulative number of new hypointense T1 lesions per patient
    All patients with new enhancing lesions, mean (SD)1.8 (2.3)0.9 (2.1)−0.9
    Patients with small new enhancing lesions only, mean (SD)0.4 (0.7)0.2 (0.4)−0.2
    Patients with at least one large new enhancing lesion,* mean (SD)2.2 (2.5)1.4 (2.8)−0.8
Proportion of enhancing lesions becoming hypointense (group lesion rates)
    With reference to any new enhancing lesions70 /500 (14.0%)24 /179 (13.4%)−0.6%
    With reference to small new enhancing lesions*38 /372 (10.2%)7 /110 (6.4%)−3.8%
    With reference to large new enhancing lesions*32 /128 (25.0%)17 /69 (24.6%)−0.4%