A Study to Evaluate Mosunetuzumab in Participants With Systemic Lupus Erythematosus With or Without Active Lupus Nephritis (SOLUNA)

A Phase II Open-Label Study to Evaluate the Efficacy, Safety, and Pharmacokinetics of Mosunetuzumab in Patients With Systemic Lupus Erythematosus With or Without Active Lupus Nephritis

This study will assess how mosunetuzumab works in people who have systemic lupus erythematosus (SLE) who may or may not also have active lupus nephritis (LN).

Study Overview

• Status: Recruiting
• Conditions: Systemic Lupus Erythematosus; Lupus Nephritis; Lupus
• Intervention / Treatment: Drug: Mosunetuzumab

• Study Type: Interventional
• Enrollment (Estimated): 30
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Reference Study ID Number: GA45799 https://forpatients.roche.com/; Phone Number: 888-662-6728 (U.S. Only); Email: global-roche-genentech-trials@gene.com

Study Locations

• Brazil
  • Estado de Bahia
    • Salvador, Estado de Bahia, Brazil, 40150-150
      • Recruiting
      • Clnica SER da Bahia
  • Federal District
    • Brasília, Federal District, Brazil, 70200-730
      • Recruiting
      • L2IP ?Instituto de Pesquisas Clínicas Ltda.
  • Mato Grosso
    • Cuiab, Mato Grosso, Brazil, 78020-500
      • Recruiting
      • IPC MT Instituto de Pesquisas Clinicas do Mato Grosso
  • Rio Grande do Sul
    • Porto Alegre, Rio Grande do Sul, Brazil, 90480-000
      • Recruiting
      • LMK Servios Mdicos S/S Ltda
  • Rio de Janeiro
    • Niterói, Rio de Janeiro, Brazil, 24030-103
      • Recruiting
      • Complexo Hospitalar de Niteroi
  • São Paulo
    • Ribeiro Preto, São Paulo, Brazil, 14048-900
      • Recruiting
      • Hospital das Clinicas de Ribeirao Preto
    • São Paulo, São Paulo, Brazil, 05403-000
      • Recruiting
      • Hospital das Clnicas da Faculdade de Medicina da USP
• Colombia
  • Barranquilla, Colombia, 080020
    • Recruiting
    • Clinica de La Costa S.A.S
  • Bogotá, Colombia, 110221
    • Recruiting
    • Centro de Investigacion en Reumatologia y Especialdades Medicas SAS. CIREEM
  • Medellín, Colombia, 050034
    • Recruiting
    • Hospital Pablo Tobon Uribe
• Italy
  • Lazio
    • Rome, Lazio, Italy, 00168
      • Recruiting
      • Fondazione Policlinico Universitario Agostino Gemelli IRCCS
  • Lombardy
    • Brescia, Lombardy, Italy, 25123
      • Recruiting
      • Azienda Socio Sanitaria Territoriale degli Spedali Civili di Brescia (Presidio Spedali Civili)
• South Africa
  • Gauteng
    • Pretoria, Gauteng, South Africa, 0002
      • Recruiting
      • Emmed Research
  • Western Cape
    • Cape Town, Western Cape, South Africa, 7925
      • Recruiting
      • University of Cape Town Kidney and Hypertension Research Unit
    • Somerset West, Western Cape, South Africa, 7130
      • Recruiting
      • Clinical Trials Network Helderberg

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Diagnosis of SLE for ≥ 6 months as assessed using the 2019 European League Against Rheumatism/American College of Rheumatology (EULAR/ACR) Classification Criteria at screening

Exclusion Criteria:

• Pregnant or breastfeeding, or intention of becoming pregnant during the study or within the time frame in which contraception is required
• Treatment with investigational therapy within 30 days or 5 drug-elimination half-lives (whichever is longer) prior to initiation of study treatment and during the study
• Major surgery requiring hospitalization during the 4 weeks prior to screening or during screening, or any planned surgery or procedure requiring hospitalization during the 12 weeks following study drug administration
• Alcohol or substance abuse within the 12 months prior to screening
• Active infection of any kind, excluding fungal infection of the nail beds
• Any major episode of infection as defined by the protocol
• History of serious recurrent or chronic infection
• History of progressive multifocal leukoencephalopathy (PML)
• Tuberculosis (TB) infection
• History of cancer, including solid tumors, hematological malignancies, and carcinoma in situ, within the past 5 years
• Active overlap syndrome with mixed connective tissue disease or systemic sclerosis within the 12 months prior to screening or during screening
• Catastrophic or severe antiphospholipid syndrome within the 12 months prior to screening or during screening. Antiphospholipid syndrome adequately controlled by anticoagulant therapy for at least 2 months prior to screening is acceptable
• High risk for clinically significant bleeding or any condition requiring plasmapheresis, IV immunoglobulin, or acute blood product transfusions
• Active severe or unstable lupus-associated neuropsychiatric disease or where, in the opinion of the investigator, it is likely to require treatment with protocol-disallowed therapies. Examples of neuropsychiatric SLE manifestations include, but are not limited to the following: meningitis, retinitis, cerebral vasculitis, myelopathy, demyelination syndromes, acute confusional state, psychosis, acute stroke or stroke syndrome, cranial neuropathy, status epilepticus or seizures, cerebellar ataxia, and mononeuritis multiplex
• History of any non-SLE disease treated with oral, intravenous, or intramuscular corticosteroids for more than 14 days in total during the one year prior to Day 1
• History of treatment with any T cell-engaging bispecific antibodies or CAR-T therapy within the past 2 years
• Receipt of any live or attenuated vaccine in the 28 days prior to or during screening

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Mosunetuzumab; Participants will receive mosunetuzumab by subcutaneous (SC) injection.	Drug: Mosunetuzumab; Participants will receive SC mosunetuzumab.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of participants who have achieved remission by Week 76	Drug-Free Remission is defined as achieving both of the following: Absence of disease activity maintained for 6 months after completion of mosunetuzumab treatment, and; not receiving any SLE-directed therapy (except for antimalarials) during the 6 months. Doses of prednisone (or equivalent) ≤5 mg/day to treat secondary adrenal insufficiency are permitted.	Up to Week 76

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percentage of participants with adverse events (AEs)		Up to 2.5 years
Serum concentration of mosunetuzumab		Up to 2.5 years
Proportion of participants who achieve Definition of Remission in SLE (DORIS) by Week 76	DORIS remission is defined as achievement of all of the following for at least 6 months: Clinical systemic lupus erythematosus disease activity index (cSLEDAI) = 0 after completion of mosunetuzumab treatment; stable dosing of SLE therapies for at least 6 months; Physician Global Assessment (PGA) of < 0.5, and; prednisone (or equivalent) dose ≤5 mg/day.	Up to Week 76
Proportion of participants who achieve Complete Renal Response (CRR) at Weeks 24, 52, 76, and 104	CRR is defined as all of the following: Urinary protein-to-creatinine ratio (UPCR) < 0.5 g/g, and; estimated glomerular filtration rate (eGFR) ≥ 85% of baseline, as calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation or ≥ 60 ml/min per 1.73 m^2 of body-surface area.	Weeks 24, 52, 76, and 104
Proportion of participants who achieve Partial Renal Response (PRR) at Weeks 24, 52, 76, and 104	PRR is defined as all of the following: ≥ 50% reduction in UPCR from baseline; UPCR < 1 g/g (or < 3 g/g if the baseline UPCR was ≥ 3 g/g), and; eGFR ≥85% of baseline, as calculated using the CKD-EPI equation.	Weeks 24, 52, 76, and 104
Longitudinal change in titers of anti-double-stranded (ds) DNA		Up to 2.5 years
Longitudinal changes in complement C3 and C4		Up to 2.5 years
Percentage of participants with anti-drug antibodies (ADAs)		Baseline up to 2.5 years
CD19+ absolute counts in blood		Up to 2.5 years
Change in Functional Assessment of Chronic Illness Therapy (FACIT) - Fatigue		Baseline to Week 76
Change in Subject's Global Assessment of Disease Activity (SGA)		Baseline to Week 76

Collaborators and Investigators

• Sponsor: Hoffmann-La Roche
• Investigators: Study Director: Clinical Trials, Hoffmann-La Roche

Study record dates

Study Major Dates

• Study Start (Actual): May 25, 2026
• Primary Completion (Estimated): February 28, 2028
• Study Completion (Estimated): August 31, 2028

Study Registration Dates

• First Submitted: February 2, 2026
• First Submitted That Met QC Criteria: May 14, 2026
• First Posted (Actual): May 20, 2026

Study Record Updates

• Last Update Posted (Actual): May 28, 2026
• Last Update Submitted That Met QC Criteria: May 27, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Urogenital Diseases; Male Urogenital Diseases; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Connective Tissue Diseases; Autoimmune Diseases; Immune System Diseases; Glomerulonephritis; Nephritis; Skin and Connective Tissue Diseases; Lupus Erythematosus, Systemic; Lupus Nephritis
• Other Study ID Numbers: GA45799; 2024-519930-22-00 (Ctis)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: For eligible studies, qualified researchers may request access to individual patient level clinical data. See Roche's commitment to transparency of clinical study information here: https://go.roche.com/data_sharing

Drug and device information, study documents

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