MERCK SERONO COMPLETES ENROLLMENT IN MS TRIAL

Merck Serono announced that patient enrollment has been completed in the CLARITY study, a Phase III pivotal clinical trial evaluating the efficacy and safety of Merck Serono's proprietary oral formulation of cladribine for the treatment of relapsing forms of multiple sclerosis (MS).

The CLARITY study is a two-year, randomized, double-blind, placebo-controlled, international trial. It enrolled more than 1,300 patients and will provide data on key endpoints including clinical relapses, disability progression and magnetic resonance imaging (MRI). Study participants have been enrolled in one of the three arms of the study to receive one of two different dose regimens of oral cladribine or matching placebo tablets. In the study, oral cladribine will be given in two or four treatment cycles in the first year, with each cycle consisting of daily administration for five consecutive days, which means study patients take oral cladribine therapy for only 10 or 20 days during the year. In the second year, two treatment cycles are administered.

The increased convenience resulting from the oral intermittent administration of oral cladribine has the potential to address an important unmet medical need in patients with MS, according to the company. Oral cladribine was granted FDA fast-track status in September. Under fast-track designation, oral cladribine is eligible for priority review and the FDA may consider portions of the marketing application for review before the new drug application is completed.

Cladribine is a small molecule that interferes with the behavior and the proliferation of certain white blood cells, particularly lymphocytes, which are involved in the pathological process of MS.