New data from Ocrevus® (Ocrelizumab) trials in relapsing and primary progressive multiple sclerosis offer new insights into the biology of MS, advancing understanding of disease progression. Researchers found that blood neurofilament light chain levels were significantly lowered following Ocrevus treatment in analyses of Phase III studies in relapsing and primary progressive MS. The data show neurofilament light chain levels may be a biomarker for predicting future disability outcomes. And separate analyses presented from one of the first studies to demonstrate neurofilament light chain levels are linked with active MRI lesions in primary progressive MS. 

Following Ocrevus treatment, blood neurofilament light chain levels were lowered to a healthy donor range in relapsing and primary progressive MS patients. Neurofilament light chain is a protein that provides structural support to nerve fibers in the brain. An increase in the amount of neurofilament light chain may be associated with nerve cell damage, and detection of increased neurofilament light chain levels in blood or cerebrospinal fluid may serve as a biomarker of nerve cell damage. 

In the Phase III OPERA I study in relapsing MS and the ORATORIO study in primary progressive MS, blood neurofilament light chain levels were significantly lower after treatment with Ocrevus. In relapsing MS, blood serum neurofilament light chain levels were reduced by 43 percent from baseline to 96 weeks after Ocrevus treatment compared with a 31 percent reduction with interferon beta-1a. In primary progressive MS, blood plasma neurofilament light chain levels were reduced by 16 percent from baseline to 96 weeks after Ocrevus treatment compared with 0.2 percent reduction with placebo. 

Additionally, these analyses showed higher blood neurofilament light chain levels at the start of the study were linked with more disability progression in upper and lower limbs in primary progressive and overall disability in the interferon beta-1a relapsing MS treatment group at 96 weeks.

New data from the Phase III OBOE study in primary progressive and relapsing MS show that primary progressive patients with active MRI lesions (gadolinium-enhancing T1 lesions) had median cerebrospinal fluid neurofilament light chain levels twice as high as those without these lesions. As previously reported, relapsing MS patients with active MRI lesions also had significantly higher neurofilament light chain levels. Collectively, these data around neurofilament light chain in MS advance the understanding of it as a potential biomarker of disease progression and may provide insight into the potential neuroprotective effects following Ocrevus treatment.

Ocrevus is the first and only therapy approved for both relapsing (including relapsing-remitting MS and active, or relapsing, secondary progressive MS, in addition to clinically isolated syndrome in the United States) and primary progressive MS. 

Findings will be presented at the 35th Congress of the European Committee for Treatment and Research in Multiple Sclerosis in Stockholm.