Figure 3.

Annualised relapse rates for overall and severe relapses (requiring steroid treatment or leading to hospitalisation) at Study Year 2 in CLARITY and Study Year 4 in CLARITY Extension (CP.3.5 mg/kg group only).

The overall ARRs for qualifying relapses differ slightly from those published in the studies by Giovannoni et al. ¹² (CT 3.5 mg/kg ARR (95% CI): 0.14 (0.12; 0.17) and Giovannoni et al. ¹³ (CP 3.5 mg/kg ARR (95% CI): 0.15 (0.09; 0.21)). The following adjustments to the methodology of the present analysis account for these differences: (1) CLARITY analyses: the calculated ARRs included imputed data for patients who experienced relapses after receiving rescue medication and the Poisson model used was not adjusted for region and (2) CLARITY Extension analyses: ARRs were calculated for the 96-week, double-blind period only, and did not include data collected over the gap period or the 24-week safety follow-up period.

ARR: annualised relapse rate; CI: confidence interval; CT 3.5 mg/kg: cladribine tablets 3.5 mg/kg; CP 3.5 mg/kg: cladribine tablets 3.5 mg/kg in CLARITY followed by placebo in CLARITY Extension.