Treatment effect of subcutaneous IFN β-1a on MRI lesion counts during the double blind period (intent-to-treat population)
| Lesions per patient per scan (point estimate) | Subcutaneous IFN β-1a three times a week versus placebo* | Subcutaneous IFN β-1a once a week versus placebo* | Subcutaneous IFN β-1a three times a week versus IFN β-1a once a week* | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Variable | Subcutaneous IFN β-1a three times a week (n=171) | Subcutaneous IFN β-1a once a week (n=175) | Placebo (n=171) | Ratio (95% CI) | p Value | Ratio (95% CI) | p Value | Ratio (95% CI) | p Value |
| CUA lesions per patient per scan | 0.50 | 0.95 | 2.58 | 0.19 (0.14 to 0.26) | <0.001 | 0.37 (0.27 to 0.50) | <0.001 | 0.52 (0.38 to 0.71) | 0.002 |
| New T2 lesions per patient per scan | 0.17 | 0.24 | 0.55 | 0.30 (0.23 to 0.40) | <0.001 | 0.43 (0.32 to 0.57) | <0.001 | 0.71 (0.53 to 0.95) | 0.012 |
| New T1 hypointense lesions per patient per scan | 0.18 | 0.26 | 0.41 | 0.43 (0.33 to 0.57) | <0.001 | 0.63 (0.48 to 0.81) | 0.004 | 0.69 (0.53 to 0.91) | 0.008 |
| New Gd+ lesions per patient per scan | 0.06 | 0.17 | 0.72 | 0.08 (0.05 to 0.13) | <0.001 | 0.24 (0.16 to 0.35) | <0.001 | 0.35 (0.23 to 0.54) | <0.001 |
*Treatment effects were estimated using a negative binomial model, with treatment, baseline lesions and randomisation stratification variables as covariates and log number of scans as an offset variable; p values were calculated using a two-sided stratified non-parametric analysis of variance model on ranked data, with effects for treatment group, baseline lesions and randomisation stratification factors.
CUA, combined unique active; Gd+, gadolinium-enhancing; IFN, interferon.