A Study of the Efficacy and Safety of BCD-281 in Patients With Relapsing-Remitting Multiple Sclerosis (MUSCAT)

A Double-blind, Randomized Clinical Study of the Efficacy and Safety of BCD-281 in Patients With Relapsing-Remitting Multiple Sclerosis

The aim of this study is to compare the efficacy, safety profile, pharmacokinetics, pharmacodynamics, and immunogenicity of BCD-281 and the reference drug in subjects with relapsing multiple sclerosis.

Study Overview

• Status: Recruiting
• Conditions: Relapsing-remitting Multiple Sclerosis (RRMS)
• Intervention / Treatment: Biological: BCD-281; Biological: Ocrelizumab

Detailed Description

The study includes the following periods:

• Screening (not more than 28 days from the date of signing the ICF).
• Double-blind period - Week 0-72.
• Open-label period - Weeks 72-96.
• Follow-up period - Weeks 96-100. The screening examination is aimed at confirming the eligibility of the subjects for the study. After confirming the eligibility, the subject will be randomized with equal probability into one of two groups (BCD-281 and the reference drug).

• Study Type: Interventional
• Enrollment (Estimated): 292
• Phase: Phase 3

Contacts and Locations

• Study Contact: Name: Marina Krasnova; Phone Number: +7 (812) 380 49 33; Email: krasnovam@biocad.ru

Study Locations

• Russia
  • Nizhny Novgorod, Russia
    • Recruiting
    • LLC "Medis"
    • Contact: Sokolova

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Provided written ICF to participate in the study.
• Male and female subjects aged 18 to 55 years inclusive at the time of signing the ICF.
• Diagnosis of multiple sclerosis, established in accordance with the McDonald criteria for the diagnosis of multiple sclerosis (2017 revision).
• Relapsing-remitting multiple sclerosis.
• The total EDSS score 0-5.5 inclusive.

• Documentary evidence of the following at the time of signing the ICF:

  1. at least one relapse within the last12 months, and/or
  2. 2 relapses within the last 24 months, and/or
  3. at least 1 T1 Gd+ lesion detected on brain MRI and 1 relapse within 24 months prior to signing the ICF.
• Presence of IgG antibodies to the Varicella-Zoster virus.
• Neurological stability for 30 days prior to signing the ICF.
• Subject's willingness to discontinue previously prescribed DMTs from the day of the first administration of the IP and throughout the study.
• The ability of the subject to follow the Protocol procedures, according to the Investigator.
• Willingness of subjects of both sexes and their sexual partners of childbearing potential to use reliable methods of contraception from the time of signing ICF, throughout the study and for 5 months after the last dose of the drug in this study.

Exclusion Criteria:

• Primary progressive or secondary progressive MS.
• MS duration of more than 10 years with EDSS score of ≤2.0 at screening.
• Malignant form of MS.
• Other medical conditions that can affect the assessment of clinical picture of the MS.
• Inability to obtain high-quality MRI images and/or the presence of contraindications to MRI and the administration of gadolinium-containing contrast agents.
• Any comorbidities requiring treatment with systemic glucocorticoids and/or immunosuppressive drugs for the duration of the study, with the exception of MS.
• History of progressive multifocal leukoencephalopathy.
• Any acute or exacerbated chronic infections detected during screening that may have a negative impact on subject's safety during the study therapy.
• Concomitant diseases and/or conditions that may affect the assessment of the clinical picture of the underlying disease and/or significantly increase the risk of AEs during the study.
• Known alcohol or drug addiction, or current signs of alcohol/drug addiction.
• History of severe depression and/or a Beck Depression Inventory score of ≥16 at screening examination.
• History of a malignant disease within 5 years prior to screening.
• A diagnosis of HIV infection, hepatitis B or C .
• Inability to provide the subject with venous access.
• Pregnancy or breastfeeding, pregnancy planning and oocyte donation throughout the study and for 5 months after the last dose of ocrelizumab.
• A history of severe allergic or anaphylactic reactions to humanized and/or murine monoclonal antibodies.
• A history of using any prohibited medications or treatments defined in the study protocol.
• Abnormal laboratory blood values, as specified in the study protocol.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: BCD-281; Subjects will receive 300 mg (for the first two infusions) and 600 mg via subsequent infusions.	Biological: BCD-281; anti-CD20 monoclonal antibody
Active Comparator: Ocrelizumab; Subjects will receive 300 mg (for the first two infusions) and 600 mg via subsequent infusions.	Biological: Ocrelizumab; anti-CD20 monoclonal antibody

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total number of T1 gadolinium-enhancing (Gd+) lesions up to Week 24.	The total number of T1 Gd+ lesions for all participants in the treatment group was calculated as the sum of the individual number of lesions at Weeks 12, 16, 20 and 24.	up to Week 24

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Annualized relapse rate (ARR).	ARR was protocol-defined and calculated as the total number of relapses for all participants in the treatment group divided by the total participant-years of exposure to that treatment.	up to Week 100
Time to first relapse.		up to Week 100
Proportion of subjects without confirmed relapses.		up to Week 100
Total number of T1 Gd+ lesions at Weeks 48, 72, 100.		up to Week 100
Total number of new or enlarged T2 lesions.		up to Week 100
Proportion of subjects without contrast-enhancing lesions.		up to Week 100
Proportion of subjects without new or enlarged T2 lesions.		up to Week 100
Total number of new hypointense T1 lesions.		up to Week 100
Change in the volume of hypointense T1 lesions.		up to Week 100
Change in the volume of T2 lesions.		up to Week 100
Combined unique active (CUA).	The total number of new T1 Gd+ lesions and new or enlarging T2 lesions, without double counting	up to Week 100
Changes over time in the neurologic deficit according to the Expanded Disability Status Scale (EDSS).	Changes in the neurologic deficit according to EEDSS to measure disability and disease progression (from 0 to 10). An increase in the EDSS score signifies worsening disability.	up to Week 100
Changes over time in Timed 25-Foot (7.62 meters) Walk Test performance.		up to Week 100
Changes over time in 9-Hole Peg Test (9HPT) performance.		up to Week 100
Changes over time in Symbol Digit Modalities Test (SDMT) performance.		up to Week 100
Change in quality of life using SF-36 questionnaire (36-Item Short Form Health Survey)	Change in the quality of life parameters using a SF-36 questionnaire. SF-36 (Short Form-36) questionnaire includes a total of 36 questions. Higher scores (0-100) mean better health.	up to Week 100
Change in quality of life using EQ-5D questionnaire (EuroQol Five Dimensions)	A positive change in the Index score or a higher score generally means improvement in health. A negative change in the Index or a lower score means deterioration.	up to Week 100
Proportion of subjects with confirmed disability progression (CDP).		up to Week 100
Proportion of subjects with confirmed disability worsening (CDW).		up to Week 100
The proportion of subjects with confirmed overall disability worsening.		up to Week 100
Proportion of patients with adverse reactions		up to Week 100
Proportion of patients with serious adverse reactions		up to Week 100
AUC 168-336.	Area under the drug concentration-time curve for the time interval from the measurable concentration on Day 169 to the measurable concentration on Day 337 (before the fourth administration of the investigational products).	up to Week 100
Cmax.	Maximum observed drug concentration.	up to Week 100
Tmax.	Time to maximum plasma concentration.	up to Week 100
T1/2.	Terminal Elimination Half-life (T1/2) of IP.	up to Week 100
Kel.	The elimination rate constant.	up to Week 100
Ceoi.		up to Week 100
Ctrough.	Trough Concentration (Ctrough) of IP.	up to Week 100
Pharmacodynamic endpoints.	PD will be evaluated based on the determination of CD19+ B-cell levels in subjects' blood.	up to Week 100
Proportion of subjects with binding antibodies (BAbs).		up to Week 100
Proportion of subjects with neutralizing antibodies (NAbs).		up to Week 100
Time to BAb/NAb positivity.		up to Week 100

Collaborators and Investigators

• Sponsor: Biocad

Study record dates

Study Major Dates

• Study Start (Actual): November 1, 2025
• Primary Completion (Estimated): December 1, 2028
• Study Completion (Estimated): December 1, 2028

Study Registration Dates

• First Submitted: November 17, 2025
• First Submitted That Met QC Criteria: December 26, 2025
• First Posted (Actual): January 6, 2026

Study Record Updates

• Last Update Posted (Actual): January 6, 2026
• Last Update Submitted That Met QC Criteria: December 26, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: Multiple Sclerosis; monoclonal antibody; anti CD20
• Additional Relevant MeSH Terms: Nervous System Diseases; Autoimmune Diseases; Immune System Diseases; Demyelinating Autoimmune Diseases, CNS; Autoimmune Diseases of the Nervous System; Demyelinating Diseases; Multiple Sclerosis; Multiple Sclerosis, Relapsing-Remitting; ocrelizumab
• Other Study ID Numbers: BCD-281-2/MUSCAT

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No