Table 3.

Phase 3 studies of natalizumab: 2-year results

	Natalizumab (n = 627)	Placebo (n = 315)	P-Value
AFFIRM (Polman et al 2006)
Clinical endpoints
Annualized relapse rate, mean (95% CI)	0.23 (0.19, 0.28)	0.73 (0.62, 0.87)	<0.001
Sustained disability progressiona, % of patients	17	29	<0.001
MRI endpoints (lesions per patient)
No. of new or enlarging T2 lesions, mean ± SD	1.9 ± 9.2	11.0 ± 15.7	<0.001
No. of Gd+ lesions, mean ± SD	0.1 ± 1.4	1.2 ± 3.9	<0.001

	Natalizumab + IFNβ−1a(n = 589)	Placebo + IFNβ−1a(n = 582)	P-Value
SENTINEL (Rudick, Stuart, et al 2006)
Clinical endpoints
Annualized relapse rate, mean (95% CI)	0.34 (0.29, 0.39)	0.75 (0.67, 0.84)	<0.001
Sustained disability progression, % of patients	23	29	0.02
MRI endpoints (lesions per patient)
No. of new or enlarging T2 lesions, mean ± SD	0.9 ± 2.1	5.4 ± 8.7	<0.001
No. of Gd+ lesions, mean ± SD	0.1 ± 0.6	0.9 ± 3.2	<0.001

^aNote: Defined as either a ≥1.0-point increase in EDSS from a baseline of ≥1.0, or a ≥1.5-point increase in EDSS from a baseline of 0.The change was required to be sustained for at least 12 weeks and could not be confirmed during a relapse.

Abbreviations: CI, confidence interval; Gd⁺, gadolinium enhancing; IFN, interferon; MRI, magnetic resonance imaging; SD, standard deviation.