Belumosudil appears to be a promising and well-tolerated therapy among patients who develop chronic graft vs host disease (cGVHD) after 2 or more lines of therapy, according to research published in Blood.
Chronic GVHD is an immune-related inflammatory disorder that can occur after allogeneic hematopoietic cell transplant for hematologic malignancies in up to 70% of treated patients. Patients who develop cGVHD are at a high risk of morbidity and non-relapse mortality (NRM). Approximately 40% of cGVHD cases are, furthermore, viewed as severe.
While first-line therapy for cGVHD usually includes corticosteroids, many patients require further treatment, either because of lack of efficacy or toxicity. Belumosudil, an oral inhibitor of Rho-associated coiled-coil–containing protein kinase 2 (ROCK2), has previously shown promise among patients with cGVHD who failed 1 to 3 prior therapy lines. For this randomized phase 2 study (ClinicalTrials.gov Identifier: NCT03640481), researchers evaluated the safety and efficacy of belumosudil among patients with steroid-resistant cGVHD.
Patients were randomly assigned to receive belumosudil 200 mg daily (66 patients) or belumosudil 200 mg twice daily (66 patients). In the overall cohort of 132 patients, the median age was 56 years (range, 21-77), 57% of patients were male sex, the median number of prior therapy lines was 3, 40% of patients had acute myeloid leukemia, and 91% had a stem cell source of peripheral blood.
The median follow-up was 14 months, at which point the best overall response rate in the once-daily group was 74% (95% CI: 62-94), compared with 77% in the twice-daily group (95% CI: 65-87). Patient organs that were affected by cGVHD all showed complete responses to therapy. The median duration of response was 54 weeks.
Adverse events (AEs) were noted in 99% of patients in the overall cohort, and grade 3 or worse events were noted in 56% of patients in the once-daily group vs 52% in the twice-daily group. A total of 12% of patients discontinued treatment because of an AE.
At the time of analysis, 1 patient in the once-daily group and 3 patients in the twice-daily group had died; 23 and 26 patients were, respectively, still receiving treatment.
“Although the 200-mg twice-daily dose showed higher responses in certain organs, such as the skin, and slightly fewer AEs, the difference compared with the 200-mg daily dose was not deemed significant,” the authors wrote.
Disclosure: The study author(s) declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Cutler C, Lee SJ, Arai S, et al. Belumosudil for chronic graft-versus-host disease after 2 or more prior lines of therapy: the ROCKstar Study. Blood. 2021;138(22):2278-2289. doi:10.1182/blood.2021012021