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Emerging treatmentsResults from peopleSubgroup finding: significant in Hispanic or Latino participants, not significant in Black participants

Post hoc analysis of two completed Phase 3 trials in relapsing MS

OPERA trials: post hoc look at disability worsening in Black and Hispanic or Latino participants

Published by MyelinWatch:

Organisation
Keck School of Medicine, University of Southern California, with Genentech and Roche · United States
Funder
F. Hoffmann-La Roche Ltd

What happened

Researchers led by the University of Southern California, with authors from Genentech, Roche and other US centres, re-analysed the OPERA I and II trials, which compared ocrelizumab with interferon beta-1a for two years in relapsing multiple sclerosis (MS). In the interferon group, non-Hispanic Black and Hispanic or Latino participants had a higher risk of disability worsening confirmed after 24 weeks, measured with a combined (composite) disability measure, than non-Hispanic White participants (hazard ratio 3.0 and 2.3). Non-Hispanic Black and Hispanic or Latino participants also had more CD19-positive B cells at the start. In 1,138 participants who consented to genetic analysis, higher African or Americas genetic ancestry was also linked to higher risk. Ocrelizumab lowered B cells in all groups. Compared with interferon, it lowered the risk of this composite disability worsening in Hispanic or Latino participants (hazard ratio 0.38; 95% confidence interval 0.20–0.72). In the 65 Black participants the estimate also pointed to lower risk (hazard ratio 0.41), but the 95% confidence interval of 0.13–1.29 includes no difference, so the result is not statistically significant.

What this means for people with MS

This is not a new treatment or a new approval: ocrelizumab is already an approved MS treatment. The analysis was done after the trials ended, in small subgroups (only 65 Black participants), using self-reported race and ethnicity; it cannot show why risk differed and does not change treatment guidance. The authors conclude that ocrelizumab reduced risk regardless of race or ethnicity, but for Black participants the study alone does not establish this. It does not establish availability or reimbursement in Greece or support changing an individual treatment without a neurologist.

About the approach studied in this programme: OPERA I and II (ocrelizumab)

Ocrelizumab is an antibody that binds CD20 on B cells and reduces that immune-cell population. OPERA I and II compared this approach with interferon beta-1a for relapsing MS during the randomized period, then followed participants receiving ocrelizumab in an open-label extension; the extension is not a continuing randomized comparison.

Approach source: JAMA Neurology — original OPERA follow-up article ↗

What kind of evidence exists?
1,628 OPERA I and II participants by self-reported race and ethnicity: 65 non-Hispanic Black, 213 Hispanic or Latino and 1,350 non-Hispanic White
How reliable is this source?
Peer-reviewed article in Multiple Sclerosis Journal; only the published abstract was reviewed. Post hoc subgroup analysis of two randomised Phase 3 trials, funded by Roche, with authors from Genentech and Roche.

Related study or programme: OPERA I and II (ocrelizumab) →

Source: Multiple Sclerosis Journal (SAGE) — peer-reviewed primary article ↗Source: Multiple Sclerosis Journal — DOI 10.1177/13524585261496124 ↗ Source: ClinicalTrials.gov — OPERA I (NCT01247324), completed with posted results ↗ Source: ClinicalTrials.gov — OPERA II (NCT01412333), completed with posted results ↗
Research event/source date
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Related substantive developments

Research event/source date:
Emerging treatmentsRegistered study in peopleStudy authorised in Greece; not a result

Phase 3 extension study authorised in Greece; recruitment not yet started

Frexalimab: Greece authorises the long-term Phase 3 extension study

Organisation: Sanofi · France

The EU Clinical Trials Information System (CTIS) shows that Greece authorised Sanofi's Phase 3 extension study LTS18002 (2026-525688-41-00) on 2 November 2026. Denmark, Portugal and Poland authorised it on the same day, after Belgium (30 October 2026) and Austria (1 November 2026); all six countries are listed as authorised with recruitment pending. The record plans 17 participants in Greece and lists four Greek hospitals: AHEPA University General Hospital of Thessaloniki, the University General Hospital of Ioannina, the General University Hospital of Larissa and the 401 General Military Hospital of Athens. The study will look at the long-term safety and tolerability of frexalimab, an experimental antibody, in people with multiple sclerosis (MS). It is open only to people who complete earlier frexalimab studies on the study drug, such as the Phase 3 studies FREXALT and FREVIVA. The estimated EU recruitment start is 15 February 2027.

Published by MyelinWatch:

What this means for people with MS

Authorisation means the study may proceed in Greece; it does not mean that it has started at any Greek hospital, that anyone has received treatment in it, or that frexalimab works. No Phase 3 results are available yet. People who are not already in a frexalimab study cannot join this extension, so it is not a way for other people with MS in Greece to receive frexalimab. Frexalimab is not an available treatment in Greece.

Read the update →Source: EU Clinical Trials Information System (CTIS), European Medicines Agency — official CTIS record ↗Source: ClinicalTrials.gov — FREXALT (NCT06141473), Phase 3, ongoing, not accepting new participants ↗ Source: ClinicalTrials.gov — FREVIVA (NCT06141486), Phase 3, ongoing, not accepting new participants ↗
Research event/source date:
Emerging treatmentsRegistered study in peopleStudy authorised in two EU countries; not a result

Phase 3 extension study authorised in two EU countries; recruitment not yet started

Frexalimab: long-term Phase 3 extension study authorised in Belgium and Austria

Organisation: Sanofi · France

The EU Clinical Trials Information System (CTIS) shows that Belgium authorised Sanofi's Phase 3 extension study LTS18002 (2026-525688-41-00) on 30 October 2026 and Austria on 1 November 2026. The study will look at the long-term safety and tolerability of frexalimab, an experimental antibody given into a vein or under the skin, in people with multiple sclerosis (MS). It is open only to people with relapsing MS or non-relapsing secondary progressive MS who complete earlier frexalimab studies on the study drug, including the Phase 3 studies FREXALT and FREVIVA. It plans 1,710 participants in total. Both countries are listed as authorised with recruitment pending; the estimated EU recruitment start is 15 February 2027.

Published by MyelinWatch:

What this means for people with MS

Authorisation means the study may proceed; it does not mean that it has started, that anyone has received treatment in it, or that frexalimab works. No Phase 3 results are available yet. People who are not already in a frexalimab study cannot join this extension. Greece authorised the study later, on 2 November 2026 (see the separate update); frexalimab is not an available treatment in Greece.

Read the update →Source: EU Clinical Trials Information System (CTIS), European Medicines Agency — official CTIS record ↗Source: ClinicalTrials.gov — FREXALT (NCT06141473), Phase 3, ongoing, not accepting new participants ↗ Source: ClinicalTrials.gov — FREVIVA (NCT06141486), Phase 3, ongoing, not accepting new participants ↗
Research event/source date:
Emerging treatmentsResults from peopleMechanism finding in a small group; no clinical result

Small laboratory study of samples from people with MS; preprint not yet peer reviewed

Preprint: a B-cell subset in neck lymph nodes was not depleted during anti-CD20 treatment

Organisation: University of Helsinki and Helsinki University Hospital · Finland

Researchers at the University of Helsinki and Helsinki University Hospital, Finland, took needle samples from deep lymph nodes in the neck, which drain fluid from the brain, and analysed single cells. They compared samples from people with newly diagnosed multiple sclerosis (MS) before treatment with samples taken during treatment: 5 people on anti-CD20 drugs (3 on rituximab, 2 on ofatumumab), 2 on dimethyl fumarate and 1 on natalizumab. In the blood, anti-CD20 treatment removed almost all B cells. In the lymph nodes, most B-cell types were clearly reduced, but one subset, called double-negative B cells, was not. These cells still carried a gene-activity pattern linked to active Epstein-Barr virus (EBV) infection, and T cells that target EBV and show signs of exhaustion also remained.

Published by MyelinWatch:

What this means for people with MS

This is an early laboratory finding in a small number of people. The authors propose that cells surviving in these lymph nodes could help explain why anti-CD20 drugs need to be given repeatedly; this was not tested. The study does not show that these drugs work less well, that the remaining cells cause relapses or disability, or that EBV drives MS during treatment. No clinical outcome was compared. The preprint has not been peer reviewed. It does not support changing an individual treatment, and it does not concern access to any treatment in Greece.

Read the update →Source: medRxiv preprint by University of Helsinki researchers — original non-peer-reviewed medical preprint ↗Source: medRxiv — preprint version 1, posted 28 October 2026 ↗ Source: Europe PMC — preprint record PPR1352381 ↗