Cladribine tablets, a novel intermittent immunosuppressant expected soon in North America, has been shown to be highly efficacious in reducing annualized relapse rates (ARR) and disability progression over a sustained period, according to the most recent data.
In the phase III CLARITY trial, subjects were randomized to placebo or one of two doses of cladribine tables (3.5 mg/kg or 5.25 mg/kg cumulative dose over two years) for two years (Giovannoni et al. N Engl J Med 2010;362:416-426). Cladribine 3.5 mg/kg was superior to placebo with respect to ARR (0.14 vs. 0.33), proportion of patients relapse-free (79.7% vs. 60.9%), and proportion free of three-month confirmed disability progression (85.7% vs. 79.4%). The mean number of active T2 lesions and gadolinium-enhancing lesions was reduced 73.4% and 85.7%, respectively, versus placebo.