Combination ruxolitinib and belumosudil is tolerable and induces responses despite treatment failure as monotherapies

FDA approved agents for the treatment of chronic GVHD including ruxolitinib and belumosudil are effective steroid-sparing agents, with overall response rates (ORR) of 76% and 65% respectively. Ruxolitinib and belumosudil are well tolerated with different primary targets. Little data is available on the use of combination ruxolitinib and belumosudil. This is a single center, retrospective analysis of 20 treatment-refractory patients with chronic GVHD treated with combination ruxolitinib and belumosudil. The ORR including complete response (CR) and partial response (PR) at any time was 55% (11/20). Among responding patients, other immunosuppressive agents were tapered or discontinued in all patients. None of the patients developed EBV or CMV reactivation requiring treatment. 4 patients (20%) developed pneumonia and 2 patients (10%) developed viral URI. Cytopenias were not exacerbated. No patients had graft failure or relapsed disease. The combination is tolerable, delays the need for alternative therapies, and facilitates tapering of corticosteroids.