Phase 3 Trial of a Natalizumab Biosimilar in Multiple Sclerosis

To establish the comparability, bioequivalence, safety, efficacy, and immunogenicity of biosimilar natalizumab (biosim-NTZ) to the reference (ref) NTZ, investigators conducted a prospective, blinded clinical trial. They randomized 264 participants with active relapsing multiple sclerosis (RMS) to biosim-NTZ or ref-NTZ.

At week 24, the mean cumulative number of new active lesions was 0.34 for biosim-NTZ and 0.45 for ref-NTZ. Annualized relapse rates were 0.21 for biosim-NTZ and 0.15 for ref-NTZ. Treatment emergent adverse events were also comparable (65% biosim-NTZ, 69% ref-NTZ). No patients with progressive multifocal leukoencephalopathy (PML) were identified. At week 48, JCV antibody conversion occurred in 6% for both biosim-NTZ and ref-NTZ…