Belumosudil reduces oral chronic graft-versus-host disease tissue inflammation and fibrosis: a ROCKstar companion study
Belumosudil (KD025), an oral, selective, Rho-associated, coiled-coil-containing protein kinase 2 (ROCK2) inhibitor, is approved for third-line treatment of chronic graft-versus-host disease (cGVHD). Previous studies demonstrated that ROCK2 inhibition reduces blood interleukin-17 (IL-17) activity and promotes regulatory T-cell (Treg cell) recovery. However, these studies did not evaluate immune responses within cGVHD-affected tissues. This study assessed tissue-level immune dynamics in 20 patients with oral cGVHD from the phase 2 ROCKstar trial, before and after 6 months of belumosudil treatment, focusing on key effector sites (oral mucosa [OM], minor salivary glands [MSGs], and skin) and the peripheral blood. After belumosudil treatment, reduction in collagen was observed in OM in parallel with decreased IL-17+ cell frequency in both OM (n = 14 pairs) and MSG (n = 11 pairs). IL-17 was primarily produced by non-T cells in the oral tissues. Immune cell frequencies in the OM decreased after treatment, whereas CD4 Treg cells increased in both the MSG and blood. Per overall or mouth-specific clinical response criteria, responders to belumosudil exhibited a reduction in collagen type I and IL-17 in the OM. Additionally, salivary transforming growth factor β1 (TGF-β1), a critical driver of fibrosis, decreased significantly, with a strong correlation observed between TGF-β1 and IL-17 levels. These findings illustrate the tissue-level response to belumosudil therapy and suggest that there is a reduction in tissue fibrosis and inflammation, thereby highlighting the therapeutic impact of ROCK2 inhibition in mitigating cGVHD. The ROCKstar study was registered at www.ClinicalTrials.gov as #NCT03640481.
Authors
- Nathaniel S. Treister
- Kathy Marshall
- Frank A. Boksa
- Corey S. Cutler (ORCID: https://orcid.org/0000-0001-8728-4314)
- Stephanie J. Lee (ORCID: https://orcid.org/0000-0003-2600-6390)
- Amin M. Alousi (ORCID: https://orcid.org/0000-0002-2498-8573)
- Rohtesh S. Mehta (ORCID: https://orcid.org/0000-0002-8532-544X)
- Iskra Pusic (ORCID: https://orcid.org/0000-0003-1725-5184)
- Bruce R. Blazar (ORCID: https://orcid.org/0000-0002-9608-9841)
- Steven Zivko Pavletic (ORCID: https://orcid.org/0000-0001-9111-9354)
- Ana Caroline Costa-da-Silva (ORCID: https://orcid.org/0000-0002-2729-5836)
- Nadarajah Vigneswaran (ORCID: https://orcid.org/0000-0002-6995-1918)
- Sandrine Macé (ORCID: https://orcid.org/0000-0001-9263-6994)
- Jacqueline Wiesehan Mays (ORCID: https://orcid.org/0000-0002-4472-9974)
- Noa G. Holtzman (ORCID: https://orcid.org/0000-0002-5706-1109)
- Olivier Schueller
- Ayesha Javaid (ORCID: https://orcid.org/0000-0002-9027-9599)
- Drashty P. Mody (ORCID: https://orcid.org/0000-0001-6597-4904)
- Yu Yao (ORCID: https://orcid.org/0009-0002-3343-3235)
- Rubina Sharma (ORCID: https://orcid.org/0000-0002-7804-0673)
- Beifang Hu
- Ran Ji (ORCID: https://orcid.org/0009-0004-7322-4352)
Institutions
- Brigham and Women's Hospital (US)
- National Institutes of Health (US)
- University of Minnesota (US)
- Cape Town HVTN Immunology Laboratory / Hutchinson Centre Research Institute of South Africa (ZA)
- The University of Texas MD Anderson Cancer Center (US)
- Washington University in St. Louis (US)
- Sanofi (France) (FR)
- National Institute of Dental and Craniofacial Research (US)
- Fred Hutch Cancer Center (US)
- Sanofi (United States) (US)
- Dana-Farber Cancer Institute (US)
- University of Minnesota Medical Center (US)
- National Cancer Institute (US)
- The University of Texas Health Science Center at Houston (US)
Publication Details
- Journal
- Blood Advances
- Published
- 2025-05-01
- DOI
- https://doi.org/10.1182/bloodadvances.2025016170
- Citations
- 4
- Primary Topic
- Hematopoietic Stem Cell Transplantation
- Type
- article
- Field-Weighted Citation Impact
- 7.08
Funders
- Eli Lilly and Company
- Sanofi
- Celgene
- Incyte
- National Institutes of Health
- University of Texas MD Anderson Cancer Center
- Pharmacyclics
- National Cancer Institute
- National Institute of Dental and Craniofacial Research