NEW ORLEANS—Analysis of pooled data from the CLARITY and ONWARD studies showed that cladribine tablets 3.5 mg/kg decreased annualized relapse rate by 57% and reduced the risk for six-month confirmed disability progression by 39% versus placebo in a population of patients with active relapsing multiple sclerosis (MS). These findings were presented at the 31st Annual Meeting of the Consortium of MS Centers.
Treatment with cladribine tablets in the CLARITY and ONWARD studies demonstrated efficacy versus placebo across a range of patients with active MS. “Combining efficacy data from the double-blind periods of these studies allows assessment of the efficacy of two years’ treatment with cladribine tablets 3.5 mg/kg,” said Gavin Giovannoni, MBBCh, PhD, on behalf of his research colleagues. Dr. Giovannoni is a Professor at the Blizard Institute at Barts and the London School of Medicine and Dentistry in London.
Gavin Giovannoni, MBBCh, PhD
Dr. Giovannoni and colleagues used pooled data from the two-year, double-blind periods of CLARITY and ONWARD to analyze the efficacy of cladribine tablets 3.5 mg/kg in patients with relapsing MS (n = 1,067) and in subgroups defined by baseline characteristics. Patients from ONWARD on cladribine tablets or placebo were also taking interferon beta. Annualized relapse rates and three-month and six-month confirmed disability progression were compared using relative risk ratios from a Poisson regression model, hazard ratios from a Cox proportional hazard model, and 95% confidence intervals for patients treated with cladribine tablets 3.5 mg/kg or placebo. The subgroups analyzed included, among others, patients with no T1 gadolinium-enhancing lesions (n = 759) or one or more T1 gadolinium-enhancing lesions (n = 308) and patients with an Expanded Disability Status Scale (EDSS) score of 3.0 or lower (n = 653) or 3.5 or greater (n = 414).
For annualized relapse rate, consistent benefits were seen with cladribine tablets 3.5 mg/kg versus placebo in the overall population (relative risk ratio: 0.43) and in the subgroups: no T1 gadolinium-enhancing lesions, 0.46; one or more T1 gadolinium-enhancing lesions, 0.38; EDSS of 3.0 or lower, 0.40; EDSS of 3.5 or greater, 0.47. Benefits favored cladribine tablets 3.5 mg/kg versus placebo in the overall population for time to three-month confirmed disability progression (hazard ratio: 0.64) and six-month confirmed disability progression (hazard ratio: 0.61) and in each of these outcomes in a majority of subgroups. For three-month confirmed disability progression: no T1 gadolinium-enhancing lesions, hazard ratio: 0.59; one or more T1 gadolinium-enhancing lesions, hazard ratio: 0.75; EDSS of 3.0 or lower, hazard ratio: 0.76; EDSS of 3.5 or greater, hazard ratio: 0.55. For six-month confirmed disability progression: no T1 gadolinium-enhancing lesions, hazard ratio: 0.59; one or more T1 gadolinium-enhancing lesions, hazard ratio: 0.66; EDSS of 3.0 or lower, hazard ratio: 0.75; EDSS of 3.5 or greater, hazard ratio: 0.51.
This study was supported by EMD Serono.