Comparison 2. Two infusions of natalizumab (300 mg or 3 mg/kg) versus placebo.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Failure to induce remission at 6 weeks	2	1034	Risk Ratio (M‐H, Fixed, 95% CI)	0.85 [0.78, 0.93]
2 Failure to induce remission at 8 weeks	3	1543	Risk Ratio (M‐H, Random, 95% CI)	0.85 [0.76, 0.95]
3 Failure to induce clinical response at 6 weeks	2	1034	Risk Ratio (M‐H, Random, 95% CI)	0.66 [0.35, 1.25]
4 Faliure to induce clinical response at 8 weeks	3	1543	Risk Ratio (M‐H, Random, 95% CI)	0.73 [0.58, 0.91]
5 Change in CDAI from baseline to 8 weeks	1	507	Mean Difference (IV, Fixed, 95% CI)	‐38.60 [‐55.26, ‐21.94]
6 Adverse events	1	129	Risk Ratio (M‐H, Fixed, 95% CI)	1.07 [0.92, 1.24]
7 Withdrawal due to adverse events	1	129	Risk Ratio (M‐H, Fixed, 95% CI)	0.95 [0.14, 6.57]
8 Serious adverse events up to week 12	1	129	Risk Ratio (M‐H, Random, 95% CI)	0.82 [0.29, 2.30]