PriMroSe
Research type
Research Study
Full title
A Phase 3, Randomized, Double-blind, Efficacy and Safety Study Comparing Orelabrutinib to Placebo in Patients with Primary Progressive Multiple Sclerosis
IRAS ID
1013270
Contact name
Kate Didio
Contact email
Sponsor organisation
Zenas BioPharma (USA) LLC
Clinicaltrials.gov Identifier
Research summary
Zenas is running a clinical research study to assess how effective orelabrutinib is in delaying disability progression in participants with Primary Progressive Multiple Sclerosis (PPMS) compared to placebo. PPMS is a type of MS where symptoms gradually worsen over time from the beginning, without distinct relapses or periods of remission. There are currently very few treatment options for individuals with PPMS. As ocrelizumab is currently the only approved disease-modifying treatment for PPMS in the UK, this research is a meaningful step toward potentially providing more options for patients. Participants will be randomly assigned to orelabrutinib 80mg once daily or placebo. Randomisation will be done in a “double blind” manner, which means the participants and the study staff will not know what treatments the participants receive. The study medication is in tablet form and participants will takeand participants will take it orally. Participants who experience an MS relapse during treatment may receive rescue medication (methylprednisolone or corticosteroid). These medications will be sourced by the UK study sites from their local supplies (standard of care in the UK).
The study is planned to last a total of approximately 32 to 62 months. This includes a screening period, treatment period of approximately 30 to 60 months and a safety follow up period of 4 weeks.
Study procedures will include: physical examinations, neurological examinations, heart traces (ECGs), liver ultrasounds, brain scans (MRIs), blood and urine tests, and completion of questionnaires about health and quality of life.
At the end of the study, participants who have completed the trial and are receiving the study treatment will be offered the opportunity to participate in a separate long term safety study.REC name
South Central - Oxford B Research Ethics Committee
REC reference
26/SC/0156
Date of REC Opinion
29 May 2026
REC opinion
Further Information Unfavourable Opinion