On July 16, 2021, the FDA accelerated the approval of belumosudil (Rezurock; Kadmon Pharmaceuticals), an oral kinase inhibitor, for the treatment of patients aged ≥12 years with chronic graft-versus-host disease (GVHD) who have received ≥2 lines of systemic therapy. Belumosudil was granted a breakthrough therapy designation for this indication.
“Rezurock represents a new treatment paradigm for thousands of chronic GVHD patients, including those with difficult-to-treat manifestations like fibrosis,” said Corey Cutler, MD, MPH, FRCPC, Associate Professor of Medicine, Harvard Medical School, and Medical Director, Adult Stem Cell Transplantation Program, Dana-Farber Cancer Institute, Boston. “Rezurock has shown robust and durable responses across the spectrum of chronic GVHD, and is safe and well-tolerated.”
Belumosudil was approved based on the KD025-213 study, a randomized, open-label, multicenter dose-ranging clinical trial of 65 patients with chronic GVHD who received belumosudil 200 mg once daily. The main efficacy measure was overall response rate (ORR) through cycle 7 of day 1.
The ORR was 75% (95% confidence interval, 63%-85%), which included 6% complete responses and 69% partial responses. The median time to first response was 1.8 months. The median duration of response was 1.9 months. Among the patients who achieved a response, no death or new systemic therapy initiation occurred in 62% of the patients for at least 12 months since the response.
The most common (≥20%) adverse events were infections, asthenia, nausea, diarrhea, dyspnea, cough, edema, hemorrhage, abdominal pain, musculoskeletal pain, headache, phosphate decreased, gamma glutamyl transferase increased, lymphocytes decreased, and hypertension.