A Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of Subcutaneously Administered Mosunetuzumab to Participants With Systemic Lupus Erythematosus

NCT05155345 | Completed Phase 1 DMC FDA Drug

• 1 other identifier: GA43191
• Study Type: interventional
• Target: 15
• Locations: 3 countries
• Sites: 3

Brief Summary

This study will evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of mosunetuzumab in participants with systemic lupus erythematosus (SLE).

Conditions

Systemic Lupus Erythematosus

Outcome Measures

Primary Outcomes (1)

• Percentage of participants with adverse events (AEs)

  For a minimum of 12 months after mosunetuzumab dose

Secondary Outcomes (4)

• Serum concentration of mosunetuzumab

  Through Month 12

• Peripheral B-cell count

  Through Month 12, then every 6 months thereafter

• Duration of B-cell depletion

  Through Month 12, then every 6 months thereafter

• Change from baseline in anti-drug antibodies (ADAs)

  Through Month 12

Study Arms (2)

Non-fractionated/Dose-finding

EXPERIMENTAL

Participants will receive a single dose of mosunetuzumab.

Drug: Mosunetuzumab; Drug: Tocilizumab

Fractionated/Dose-escalation

EXPERIMENTAL

Participants will receive a fractionated (divided) dose of mosunetuzumab on Days 1 and 8.

Drug: Mosunetuzumab; Drug: Tocilizumab

Interventions

Mosunetuzumab DRUG

Participants will receive subcutaneous (SC) mosunetuzumab on either Day 1 or on Days 1 and 8.

Fractionated/Dose-escalation; Non-fractionated/Dose-finding

Tocilizumab DRUG

Participants will receive intravenous (IV) tocilizumab as needed to manage adverse reactions.

Fractionated/Dose-escalation; Non-fractionated/Dose-finding

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Diagnosis of SLE according to the 2019 European League Against Rheumatism/American College of Rheumatology Classification Criteria at least 12 weeks or more prior to screening
• Presence of one or more of the following SLE autoantibodies documented within the 12 months prior to screening or during screening: positive ANA (greater than or equal to 1:160); anti dsDNA above the upper limit of normal (ULN); anti-Sm above the ULN
• Active SLE disease, as demonstrated by a SLEDAI-2K total score of greater than or equal to 4 at screening
• Current receipt of one or more of the following classes of standard therapies for the treatment of SLE at stable doses: oral corticosteroids (OCSs), antimalarial agents, conventional immunosuppressants
• For women of childbearing potential: agreement to remain abstinent (refrain from heterosexual intercourse) or use contraception as defined by the protocol
• For men on mycophenolate mofetil (MMF): With a female partner of childbearing potential, men who are not surgically sterile must remain abstinent (refrain from heterosexual intercourse) or use contraception as defined by the protocol

You may not qualify if:

• Pregnant or breastfeeding, or intending to become pregnant during the study or within 3 months after the final dose of mosunetuzumab and 3 months after the final dose of tocilizumab
• Active severe or unstable lupus-associated neuropsychiatric disease that is likely to require treatment with protocol-prohibited therapies
• Active overlap syndrome with mixed connective tissue disease or systemic sclerosis within 12 months prior to screening or during screening
• Catastrophic or severe antiphospholipid syndrome within 12 months prior to screening or during screening
• Presence of significant lupus-associated renal disease and/or renal impairment that is likely to require treatment with protocol-prohibited therapies
• Peripheral CD19+ B-cell count \< 25 cells/uL
• Receipt of an investigational therapy within 30 days or 5 drug-elimination half-lives (whichever is longer) prior to initiation of study treatment and during the study
• Receipt of any of the following excluded therapies: any anti-CD19 or anti-CD20 therapy such as blinatumomab, obinutuzumab, rituxumab, ocrelizumab, or ofatumumab less than 12 months prior to screening or during screening; inhibitors of JAK, Bruton tyrosine kinase, or tyrosine kinase 2, including baricitinib, tofacitinib, upadacitinib, filgotinib, ibrutinib, or fenebrutinib, or any investigational agent within 30 days prior to screening or during screening; tacrolimus, ciclosporin, or voclosporin within 30 day prior to screening or during screening; cyclophosphamide or a biologic therapy such as but not limited to belimumab, ustekinumab, anifrolumab, secukinumab, or atacicept during 2 months prior to screening or during screening; any live or attenuated vaccine during 28 days prior to screening or during screening
• High risk for any clinically significant bleeding or any condition requiring plasmapheresis, IV immunoglobulin, or acute blood product transfusions
• Significant or uncontrolled medical disease that would preclude participation
• HIV infection, acute or chronic hepatitis B virus (HBV), acute or chronic hepatitis C (HCV) infection, tuberculosis (TB) infection, known or suspected chronic active Epstein-Barr virus (EBV) infection, or cytomegalovirus (CMV) infection
• Active infection of any kind, excluding fungal infection of the nail beds
• Any major episode of infection that fulfills any of the following criteria: requires hospitalization during 8 weeks prior to screening or during screening; requires treatment with IV antibiotics (or anti-infective medications) during 8 weeks prior to screening or during screening; requires treatment with oral antibiotics (or anti-infective medications) during 2 weeks prior to screening or during screening
• History of serious recurrent or chronic infection
• History of progressive multifocal leukoencephalopathy (PML)

Sponsors & Collaborators

• Hoffmann-La Roche: lead

Study Sites (3)

Pinnacle Research Group

Anniston, Alabama, 36207, United States

Location

ICS ARENSIA Exploratory Medicine

Chisinau, MD-2025, Moldova

Location

Szpital Uniwersytecki Nr 2 im. Dr Jana Biziela w Bydgoszczy

Bydgoszcz, 85-168, Poland

Location

MeSH Terms

Conditions

Lupus Erythematosus, Systemic

Interventions

tocilizumab

Condition Hierarchy (Ancestors)

Connective Tissue Diseases; Skin and Connective Tissue Diseases; Autoimmune Diseases; Immune System Diseases

Study Officials

• Clinical Trials

  Hoffmann-La Roche

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SEQUENTIAL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 10, 2021
• First Posted: December 13, 2021
• Study Start: January 11, 2022
• Primary Completion: December 17, 2024
• Study Completion: December 17, 2024
• Last Updated: April 29, 2025

Record last verified: 2025-04

Data Sharing

• IPD Sharing: Will share

Locations

US (1); MO (1); PL (1)