Biogen Inc. announced that first patient has been enrolled in a global Phase 3b study evaluating the efficacy and safety of extended interval dosing (EID; every six weeks) for natalizumab compared to standard interval dosing (SID) in patients with relapsing multiple sclerosis (MS). The new study, NOVA, is a two-year, prospective, randomized, interventional, controlled, open-label, rater-blinded, international Phase 3b study that will assess the efficacy, safety and tolerability of six-week natalizumab dosing intervals in people with relapsing-remitting MS. Patients who switch to EID after one year of treatment with natalizumab SID will be evaluated in relation to patients receiving continued SID treatment. The study will enroll approximately 480 patients worldwide. The primary endpoint is the number of new or newly enlarging T2 hyperintense lesions at week 48. NOVA was initiated following analyses that showed that EID was associated with a significant reduction in the risk of progressive multifocal leukoencephalopathy (PML), a rare but serious brain infection. The pre-specified, retrospective analysis of the U.S. TOUCH (TYSABRI® Outreach: United Commitment to Health) REMS program examined the impact of EID as compared to SID on the risk of PML, and the NOVA study aims to assess the efficacy of EID natalizumab to further evaluate the drug’s benefit-risk profile.