A Study to Investigate the Efficacy of Fenebrutinib in Relapsing Multiple Sclerosis (RMS)

Study Overview
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Brief Summary
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This is a study evaluating the effect of fenebrutinib on brain magnetic resonance imaging (MRI) in participants with RMS. The safety and pharmacokinetics of fenebrutinib will also be evaluated. Participants will be randomized to receive either fenebrutinib or placebo.

Official Title
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A Randomized, Double-Blind, Placebo-Controlled Study to Investigate the Efficacy of Fenebrutinib in Relapsing Multiple Sclerosis

Conditions
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Relapsing Multiple Sclerosis

Intervention / Treatment
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* Drug: Fenebrutinib
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: A diagnosis of RMS in accordance with the revised 2017 McDonald Criteria. Expanded Disability Status Scale (EDSS) score of 0 - 5.5 at screening. For female participants of childbearing potential: agreement to remain abstinent (refrain from heterosexual intercourse) or use contraceptive measures, and refrain from donating eggs. For male participants: agreement to remain abstinent (refrain from heterosexual intercourse) or use contraceptive measures, and refrain from donating sperm. Exclusion Criteria: Disease duration of > 10 years from the onset of symptoms and an EDSS score at screening < 2.0. Female participants who are pregnant or breastfeeding, or intending to become pregnant. Male participants who intend to father a child during the study. A diagnosis of Primary Progressive Multiple Sclerosis (PPMS) or non-active Secondary Progressive Multiple Sclerosis (SPMS). Any known or suspected active infection at screening, including but not limited to a positive screening tests for Hepatitis B and C, an active or latent or inadequately treated infection with tuberculosis (TB), a confirmed or suspected progressive multifocal leukoencephalopathy (PML). History of cancer including hematologic malignancy and solid tumors within 10 years of screening. Presence of other neurological disorders that could interfere with the diagnosis of MS or with the assessments of safety or efficacy during the study. Clinically significant cardiovascular, psychiatric, pulmonary, renal, hepatic, endocrine, metabolic or gastrointestinal disease. Any concomitant disease that may require chronic treatment with systemic corticosteroids or immunosuppressants during the course of the study. History of alcohol or other drug abuse within 12 months prior to screening. History of or currently active primary or secondary (non-drug-related) immunodeficiency, including known history of HIV infection. Inability to complete an MRI scan. Adrenocorticotropic hormone or systemic corticosteroid therapy within 4 weeks prior to screening. Receipt of a live-attenuated vaccine within 6 weeks prior to randomization. Any previous treatment with immunomodulatory or immunosuppressive medication without an appropriate washout period.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 55 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Fenebrutinib<br>Participants will receive oral fenebrutinib. | Drug: Fenebrutinib<br>* Fenebrutinib will be administered orally.<br>|
| Placebo Comparator: Placebo<br>Participants will receive oral placebo. | Drug: Placebo<br>* Placebo will be administered orally.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total Number of New Gadolinium-Enhancing T1 Lesions Observed on MRI Scans of the Brain |  | 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of New or Enlarging T2-Weighted Lesions Observed on MRI Scans of the Brain |  | Weeks 4, 8 and 12 | 
| Percentage of Participants Free From any New Gadolinium-enhancing T1 Lesions and New or Enlarging T2-Weighted Lesions Observed on MRI Scans of the Brain |  | Weeks 4, 8 and 12 | 
| Percentage of Participants with Adverse Events (AEs) |  | Up to 192 weeks | 
| Plasma Concentrations of Fenebrutinib at Specified Timepoints |  | Up to 192 weeks |