Stephanie Lee, MD, MPH, David Giuliani and Patricia Giuliani/Oliver Press Endowed Chair, Professor, Division of Cancer Research, Fred Hutchinson Cancer Center, Associate Director, Clinical Research, of the Phase 3 ROCKstar trial (NCT03640481) (talking about 3-year follow-up data) evaluating vermosudil (Rezurock) for chronic graft-versus-host disease (cGVHD) and highlighting the importance of these findings.
In July 2021, FDA approves belumosdi, an oral selective rho-associated coiled-coil-containing protein kinase 2 inhibitorl For the treatment of adult and pediatric patients 12 years and older with cGVHD that has progressed on two or more prior systemic therapies. This regulatory decision was supported by safety and efficacy data from the ROCKstar trial (KD025-213). Previously reported data showed that the drug induced high overall response rates at doses of 200 mg per day and 200 mg twice daily after a median follow-up of 14 months. .
Given the evolving landscape of cGVHD treatment and the need for longer-term follow-up data, researchers sought to provide a comprehensive evaluation of treatment efficacy and safety over a 3-year period. Ta. This long-term follow-up study was critical to see if these initial results persisted over time.
This open-label, multicenter trial enrolled 152 patients with cGVHD who had previously received 2 to 5 lines of systemic therapy, including 20 unreported participants enrolled in a subsequent biomarker study. was included. Patients in the modified intention-to-treat (mITT) population received 1 of 2 vermosudil dose levels.
Extended follow-up data from this study 2024 Transplant and Cell Therapy Conference, Lee begins, demonstrating Belmosudil’s sustained efficacy and minimal toxicity. In the 200 mg once daily arm, he observed a 3-year overall response rate (ORR) of 74%, and in the 200 mg twice daily arm, he observed a 76% overall response rate (ORR). Ta. Remarkably, the response rate remained stable as population size and vermosudil exposure increased, and consistent responses were observed across all organ systems. Failure-free survival (FFS) with vermosudil was 44.1% in the mITT population and 51.8% in the responder population. Additionally, the overall duration of response (DOR) with vermosudil increased from 51.4% in the original analysis to 77.1% in the follow-up analysis, Lee said.
Despite further exposure to vermosudil, no new safety signals were identified. Overall, 21.0% and 13.2% of participants discontinued treatment due to cGVHD progression or toxicity, respectively. However, after each year of follow-up, the rate of treatment discontinuation due to progression of cGVHD or AEs decreased, Lee explained.
These data are particularly encouraging for oncologists in regions where these new treatment options may be limited. Ultimately, she concludes, this study highlights the potential for patients to maintain a response to the drug over long periods of time without experiencing increased toxicity.
