Ocrelizumab Treatment Safe, Effective After 96 Weeks in Minority Groups With MS

Ocrelizumab reduces neurofilament light chain (NfL) levels and prevents the development of contrast-enhancing lesions (CELs) and new or enlarging T2 lesions (NET2L) among Black and Hispanic patients with relapsing multiple sclerosis (MS), according to study results presented at the Americas Committee for Treatment and Research in Multiple Sclerosis (ACTRIMS) Forum 2025, held in West Palm Beach, Florida from February 27 to March 1.

Although Black and Hispanic populations have higher incidence rates of MS, they are underrepresented in clinical trials.

The CHIMES trial (ClinicalTrials.gov Identifier: NCT04377555) was a prospective, open-label, phase 4 study that recruited Black and Hispanic patients with relapsing MS. Researchers evaluated patients with relapsing MS (N=182) for the change in magnetic resonance imaging (MRI) and blood biomarker activities after 96 weeks of ocrelizumab therapy. Outcomes from CHIMES were compared with those from the OPERA I/II (ClinicalTrials.gov Identifier: NCT01247324/NCT01412333) and OBOE (ClinicalTrials.gov Identifier: NCT02688985) trials.

Throughout the 96 weeks of ocrelizumab treatment:

• 96.3% of Black patients with relapsing MS and 98.6% of Hispanic patients with relapsing MS did not develop CELs
• 46.4% and 62.3% did not develop NET2Ls, and
• 51.4% and 69.9% did not develop T1 hypointense lesions (T1HLs), respectively.

During ocrelizumab treatment, the patients with relapsing MS had a reduction in total brain volume of -0.69% (P <.001), cortical gray matter volume of -0.79% (P <.001), and thalamic volume of -1.7% (P <.001) relative to baseline. In addition, T2 lesion volume decreased by -5.9% (P <.001) relative to baseline whereas no change in T1HL volume was observed (P =.1).

Ocrelizumab associated with a -48.1% reduction in average blood NfL levels from baseline, in which the decrease in NfL levels was more pronounced among patients with CELs at baseline (mean difference [MD], -62.7%) than those without (MD, -35.9%).

The MRI disease activity observed in CHIMES was consistent with observations from the OPERA I/II trial. The changes in NfL observed in CHIMES was similar to what was reported in OBOE, however, in contrast to the increase in blood glial fibrillary acidic protein (GFAP) levels in OBOE, patients with relapsing MS in CHIMES had a decrease in GFAP from baseline of -4.4%.

“Our data indicating the prevention of new CELs and NET2Ls and reductions in NfL support the efficacy of 96-week [ocrelizumab] treatment in [Black people with relapsing MS] and [Hispanic people with relapsing MS]. […] Results from the ongoing CHIMES trial continue to support the efficacy and safety of [ocrelizumab] in [Black people with relapsing MS] and [Hispanic people with relapsing MS].”

Disclosure: This research was supported by Genentech, Inc. Please see the original reference for a full list of disclosures