A Study to Investigate the Efficacy and Safety of Belumosudil Compared With Best Available Therapy in Participants Aged 12 Years or Older With Chronic Graft-versus-host Disease

A Parallel Group, Phase 3, Randomized, Open-label, 2-arm Study to Demonstrate the Superiority of Belumosudil Versus Best Available Therapy (BAT) in Participants at Least 12 Years of Age With Chronic Graft Versus Host Disease (cGVHD) Refractory to or Recurrent After 2 to 5 Prior Lines of Systemic Therapy

Participants will be randomized 1:1 to receive either belumosudil or Best Available Therapy (BAT), with stratification based on baseline cGVHD severity as defined by the 2014◦NIH consensus criteria (moderate versus severe), use of concomitant CS and/or CNI (ie, tacrolimus or cyclosporine) at baseline (Yes versus No), and the number of prior lines of therapies (2 versus more than 2). While treatment practices for cGVHD differ across regions, ruxolitinib has been approved by the European Commission since May 2022 and is expected to be broadly accessible throughout most EU member states by study initiation. The study will target patients post-ruxolitinib treatment, except where Investigators deemed ruxolitinib treatment for cGVHD not suitable. In the BAT arm, the study doctor will select one BAT based on clinical judgement, local availability etc. prior to randomization.

Participants randomized to the BAT arm will have the option to cross-over to open-label belumosudil treatment upon meeting predefined criteria.

Study details include:

• The study duration will be defined as 3 years from LPI.

• Individual participant duration on study will consist of:

  • Up to 28 days for screening.
  • Treatment until clinically significant progression of cGVHD, relapse/recurrence of the underlying disease, start of a new systemic treatment for cGVHD (except change from BAT to belumosudil during the cross-over), experience of an unacceptable adverse event, request from participant or Investigator, or until the end of the study is reached, whichever comes first.
  • Thirty days of post treatment safety follow-up.
  • Follow-up for cGVHD status as applicable.
  • Long-term follow-up until death or end of study, whichever occurs first.

Study Overview

• Status: Not yet recruiting
• Conditions: Chronic Graft Versus Host Disease
• Intervention / Treatment: Drug: Belumosudil; Other: Best available therapy (BAT)

• Study Type: Interventional
• Enrollment (Estimated): 356
• Phase: Phase 3

Contacts and Locations

• Study Contact: Name: Trial Transparency email recommended (Toll free for US & Canada); Phone Number: option 6 800-633-1610; Email: contact-us@sanofi.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Participant must be at least 12 years of age at the time of signing the informed consent.
• Participants who have undergone allo-HCT.
• Participants with active moderate to severe cGVHD at the time of enrollment, defined using the NIH Consensus diagnosis and staging criteria for which the physician believes a new line of systemic therapy is required.
• Participant receiving systemic CNI and/or CS must be on a stable dose/regimen (prednisone equivalent <1 mg/kg/day for CS) for at least 2 weeks prior to randomization.
• cGVHD is refractory to, or has recurred following, at least 2 prior lines of systemic treatment. Participants must have received a minimum of 2 and a maximum of 5 prior systemic therapies for cGVHD.
• Participant must have received ruxolitinib for the treatment of cGVHD unless the Investigator believes treatment with ruxolitinib for cGVHD was not suitable for the participant.

• Participants and/or their LAR must accept to be treated with 1 of the following BAT options as recommended to them by the Investigator on Cycle 1 Day 1:

  • ECP,
  • Low-dose MTX,
  • MMF,
  • Rituximab,
  • mTOR inhibitors (sirolimus, everolimus)
  • Imatinib,
  • Ibrutinib,
  • Proteasome inhibitors,
  • Pentostatin.
• Body weight ≥ 30 kg I 09. Life expectancy of > 6 months.
• Contraceptive use by men and women should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies.

Exclusion Criteria:

• Any evidence (histologic, cytogenetic, molecular, hematologic, or mixed) of progressive or relapsed underlying disease or post-transplant lymphoproliferative disease after most recent allo-HCT.

• Participants who meet any of the following criteria regarding systemic cGVHD treatments:

  • Participants who newly initiated any systemic cGVHD treatment within 14 days prior to the date of randomization.
  • Participants receiving systemic ruxolitinib treatment who are unable to meet the following requirements:
• Ruxolitinib must be tapered and discontinued within 14 days following the first dose of belumosudil or BAT (allowing for a maximum overlap period of up to 14 days with belumosudil or BAT treatment).

• No dose increases of ruxolitinib are permitted from 14 days prior to the date of randomization until permanent discontinuation of ruxolitinib (dose reductions and discontinuations are permitted during this period).

  • Participants receiving other systemic cGVHD treatment (apart from CS and CNI) including investigational treatments who have not completed a washout period of at least 14 days or 5 half-lives (whichever is shorter) prior to the first dose of belumosudil or BAT treatment.

Note: Topical and organ-specific treatment for cGVHD and other supportive agents are allowed.

• Participant has had previous exposure to belumosudil.
• Participants with a Karnofsky Performance Scale (KPS) score <60 (if aged ≥16 years) or Lansky Performance Score of <60 (if aged <16 years).
• Clinically uncontrolled chronic or ongoing infectious disease requiring antibiotic, antiviral, or antifungal treatment within 14 days prior to the date of randomization.
• Impairment of GI function (unrelated to cGVHD) or GI disease (unrelated to cGVHD) that may significantly alter the absorption of belumosudil (such as ulcerative disease, malabsorption syndrome, uncontrolled nausea, vomiting, diarrhea, or small bowel resection).
• Administration of live or live-attenuated vaccines is prohibited within 28 days or 5 elimination half-lives of the respective vaccine, whichever is longer, prior to study treatment administration and until study intervention discontinuation.
• Has a forced expiratory volume in the first second (FEV1) ≤39% or has lung score of 3 according to 2014 NIH consensus diagnostic and staging criteria.

• Has any of the following lab results:

  • Absolute neutrophil count <1.5 × 10⁹/L (for participants aged <18 years) or <1.0 × 109/L (for participants aged ≥18 years). The use of G-CSF is not allowed within 7 days before the screening hematological test.
  • Platelet count <50 × 10⁹/L (for participants aged <18 years) or <25 × 109/L (for participants aged ≥18 years). Platelet transfusions are not allowed within 72 hours before the screening hematological test.
  • ALT and/or AST >3 × ULN (>5 × ULN if abnormalities are due to cGVHD).
  • Total bilirubin >1.5 × ULN (>3 × ULN if Gilbert's syndrome or due to cGVHD).
  • eGFR <30 mL/min/1.73 m2 using the MDRD-4 variable formula (if aged ≥18 years) or using the Bedside Schwartz formula (if aged <18 years).
• Participants with active viral diseases
• Diagnosed or treated for another malignancy other than the underlying disease allo-HCT was indicated for, within 3 years prior to randomization with the exception of complete resection of basal cell carcinoma or squamous cell carcinoma of the skin, an in-situ malignancy, or low risk prostate cancer after curative therapy.
• Hepatic impairment classified as Child-Pugh C or worse, with the exception of transient liver impairment attributable to GVHD.

The above information is not intended to contain all considerations relevant to a participant's potential participation in a clinical trial.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Belumosudil; Participants will receive belumosudil	Drug: Belumosudil; Pharmaceutical form:Tablet-Route of administration:oral; Other Names: SAR445761
Other: best available therapy(BAT); Participants will receive BAT based on the Investigator's judgment	Other: Best available therapy (BAT); Participants will receive BAT based on the Investigator's judgment

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Overall response rate	Overall response rate at 24 weeks defined as the proportion of participants who achieve an overall response (PR or CR) without the requirement of new systemic therapy as per NIH consensus response criteria (2014) at Week 24.	at week 24

Secondary Outcome Measures

Outcome Measure	Time Frame
Time from the date of randomization to the date of start of new systemic treatment for cGVHD, relapse or recurrence of underlying disease, or death, whichever occurs first.	Until the end of study, up to approximately 3 years from Last Participant In
Proportion of participants achieving at least 6-point reduction from baseline in the modified Lee cGVHD Symptom Scale score at Week 24.	at 24 week
Proportion of participants who achieve an overall response (CR or PR) within up to 24 weeks and without the requirement of new systemic therapy as per NIH consensus response criteria (2014).	up to 24 weeks
Proportion of participants who achieve an overall response (CR or PR) based on NIH consensus response criteria (2014) at any time until start of new systemic therapy for cGVHD.	Until the end of study, up to approximately 3 years from Last Participant In
The time from first response of PR or CR until documented progression, new systemic treatment for cGVHD, or death, whichever occurs first.	Until the end of study, up to approximately 3 years from Last Participant In
Time from randomization to the first response (either CR or PR) per NIH consensus response criteria (2014) for cGVHD.	Until the end of study, up to approximately 3 years from Last Participant In
Time from the date of randomization to the date of starting a new systemic therapy for cGVHD.	Until the end of study, up to approximately 3 years from Last Participant In
Proportion of participants who achieve CR or PR based on NIH consensus criteria (2014) at any time point in each involved organ and before the start of new systemic therapy for cGVHD.	Until the end of study, up to approximately 3 years from Last Participant In
The time from the date of randomization to the date of death from any cause.	Until the end of study, up to approximately 3 years from Last Participant In
Proportion of participants with >50% reduction from baseline in daily CS dose at Week 24.	at Week 24
Proportion of participants with discontinuation of CS at Week 24.	at Week 24
Proportion of participants with >50% reduction from baseline in daily CNI dose at Week 24.	at Week 24
Proportion of participants with discontinuation of CNI at Week 24.	at Week 24
Incidence of TEAEs, SAEs, and AESIs.	From first dose of study treatment until 30 days after last dose (up to 3.3 years)
The cumulative incidence of relapse or recurrence of the underlying disease at any time during the study.	Until the end of study, up to approximately 3 years from Last Participant In
Belumosudil plasma concentrations.	at Cycle 1 Day 15, Cycle 2 Day 1, Cycle 4 Day 1 and Cycle 7 Day 1. A cycle is defined as a 28-day period
Change from baseline in SF-36v2 domain scores and composite Physical Component Summary (PCS) and Mental Component Summary (MCS) scores.	From Cycle 1 Day 1 to End of Treatment Visit (up to 3.3 years). A cycle is defined as a 28-day period

Collaborators and Investigators

• Sponsor: Sanofi

Publications and helpful links

Helpful Links

• For EU sites click here and navigate to 'Locations and contact points'

Study record dates

Study Major Dates

• Study Start (Estimated): September 7, 2026
• Primary Completion (Estimated): September 14, 2029
• Study Completion (Estimated): March 2, 2032

Study Registration Dates

• First Submitted: August 4, 2026
• First Submitted That Met QC Criteria: August 14, 2026
• First Posted (Actual): August 18, 2026

Study Record Updates

• Last Update Posted (Actual): September 15, 2026
• Last Update Submitted That Met QC Criteria: September 11, 2026
• Last Verified: September 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Organizing Pneumonia; Immune System Diseases; Respiratory Tract Diseases; Lung Diseases; Bronchial Diseases; Lung Diseases, Obstructive; Bronchiolitis Obliterans; Bronchiolitis; Bronchitis; Graft vs Host Disease; Bronchiolitis Obliterans Syndrome; belumosudil
• Other Study ID Numbers: EFC22965; 2026-525913-30 (Registry Identifier: CTIS)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants. Further details on Sanofi's data sharing criteria, eligible studies, and process for requesting access can be found at: https://vivli.org

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: Yes