Brain volume loss with Ocrevus similar to healthy aging: Study
Rebif patients had significantly higher rate of atrophy across all measures
Ocrevus (ocrelizumab) reduces brain volume loss in people with relapsing forms of multiple sclerosis (MS) to levels similar to those seen in healthy aging, a small study reports.
“These findings are consistent with an important role of inflammation on overall tissue loss and the role of ocrelizumab in reducing this phenomenon,” researchers wrote in “Ocrelizumab-treated patients with relapsing multiple sclerosis show volume loss rates similar to healthy aging,” which was published in the Multiple Sclerosis Journal.
Ocrevus, marketed by Genentech, a Roche subsidiary, is an approved treatment that destroys B-cells, immune cells that produce antibodies and are involved in MS inflammation.
Data from the OPERA I (NCT01247324) and OPERA II (NCT01412333) Phase 3 clinical trials supported its approval for relapsing types of MS. Results showed nearly two years of Ocrevus outperformed Rebif (interferon beta-1a), an older approved medication, at reducing relapse rates and preventing disability progression.
The number of brain lesions, as well as total brain volume loss (brain atrophy), also were significantly reduced.
To see if brain atrophy rates in Ocrevus-treated patients drop to levels similar to healthy aging, researchers at Roche and at the University of British Columbia, Canada examined brain volume loss in patients in the OPERA trials. The findings were compared with healthy volunteers without a neurological disease, matched to patients in age and sex.
Brain volume loss reductions with Ocrevus
A total of 30 patients recruited to the OPERA trials at the University of British Columbia and 44 healthy controls were included.
MRI scans measured the rate of volume loss in the whole brain and in multiple brain regions, such as the cerebellum, which plays an important role in motor control, and the thalamus, which relays motor and sensory information from the body to the brain.
The researchers also measured atrophy rates in the brain’s white matter, which is mainly made of nerve fibers connecting different brain regions, and gray matter, composed of nerve cell bodies.
Results showed no differences in atrophy rates between Ocrevus-treated patients and healthy controls. Similar findings were seen when all Ocrevus-treated patients from the OPERA trials were included, with the exception of a small but significant difference for whole brain volume loss.
In contrast, Rebif-treated patients had a significantly higher rate of atrophy across all measures compared with the healthy controls, demonstrating that Ocrevus was highly effective at slowing brain volume loss.
The percentage of annual changes in brain volume was similar between healthy controls and the broad Ocrevus-treated patients. In both, researchers detected higher changes in gray matter regions, particularly the thalamus, and smaller changes in white matter and cerebellum volumes, which is consistent with healthy aging.
“Our findings suggested that, after ocrelizumab reached its full efficacy, patients with [relapsing MS] showed volume loss rates approaching that of healthy aging controls,” both across the whole brain and in specific brain regions, the researchers wrote.