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Emerging treatmentsResults from peopleOverall 10-year disability finding; extension-only and PIRA comparisons not significant

Post hoc 10-year follow-up analysis of two Phase 3 trials in relapsing MS

Ocrelizumab: full 10-year OPERA I and II analysis published

Published by MyelinWatch:

What happened

Published online on 5 October 2026, the full OPERA I and II follow-up analysis covers 1,656 people randomized with relapsing multiple sclerosis (MS). Ocrelizumab was compared with interferon beta-1a for two blinded years; participants entering the open-label extension then received ocrelizumab for up to eight more years. Across the full period, earlier ocrelizumab was associated with a lower hazard of disability progression confirmed for 48 weeks (hazard ratio 0.76; 95% confidence interval 0.61–0.95). The difference was largely established during the randomized period. After the switch, the extension-only comparison did not show a new difference (hazard ratio 1.02; 95% confidence interval 0.81–1.28).

What this means for people with MS

This adds full peer-reviewed long-term evidence for earlier treatment in relapsing MS, but the 10-year comparison was not randomized throughout: 853 of 1,656 originally randomized participants completed follow-up. Attrition and post hoc analysis limit causal interpretation. The 10-year comparison for progression independent of relapse activity (PIRA) was not statistically significant; this paper does not prove remyelination or effects in primary progressive MS. Serious infections and declining IgG occurred, so stable observed adverse-event rates do not mean no risk. This paper does not establish Greek availability or reimbursement.

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?
Peer-reviewed JAMA Neurology original investigation; 2-year randomized comparison followed by open-label extension
How reliable is this source?
JAMA Neurology peer-reviewed original paper dated 5 October 2026; Roche funded the study and participated in design, analysis, interpretation and editorial work. Official OPERA I/II registry records checked separately.
Source: JAMA Neurology — peer-reviewed paper ↗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.

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.

Research event/source date:
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

Organisation: Keck School of Medicine, University of Southern California, with Genentech and Roche · United States

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.

Published by MyelinWatch:

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.