Belumosudil for cGvHD: 3-year follow-up from the ROCKstar trial

Chronic graft-versus-host disease (cGvHD) is characterized by inflammation, fibrosis, and tissue damage, and can have a profound impact on quality of life.¹ Up to 70% of patients who receive an allogeneic stem cell transplant may be affected by cGvHD.¹

Belumosudil, an oral selective Rho-associated coiled coil-containing protein kinase 2 (ROCK2) inhibitor, dually inhibits the inflammation and fibrosis that occurs in cGvHD. Inhibition of ROCK2 leads to downregulation of STAT3 phosphorylation, and restores the Th17/Treg cell balance through a STAT5 pathway, increasing the proportion of Treg cells.^1,2  By preventing ROCK2 activation through profibrotic mediators, belumosudil also blocks differentiation of fibroblasts into myofibroblasts.¹

The phase II ROCKstar trial (NCT03640481) evaluated belumosudil 200 mg once or twice daily in 132 patients with heavily pre-treated cGvHD;¹ the 3-year follow-up data includes a further 20 patients enrolled in a subsequent biomarker study.² Patients (N = 152) were evaluated for safety and efficacy for up to 3 years.²

Responses to belumosudil were sustained through 3 years of follow-up, with no new safety signals observed.² Fewer patients in the 200 mg BID arm discontinued due to disease progression and adverse events compared to the 200 mg QD arm (13.2% vs 21%, respectively). This demonstrates belumosudil can be an effective treatment option for heavily pretreated patients with cGvHD.²