RHX-317

RHX-317 is an investigational, orally administered small molecule inhibitor of mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1), being developed by Rheos Medicines as a targeted therapy for autoimmune and inflammatory diseases, with an initial focus on chronic graft-versus-host disease (cGVHD).[1][2][5][9] By allosterically inhibiting MALT1’s paracaspase activity at a central “anabolic hub” in immune cells, RHX-317 is designed to attenuate effector functions and inflammatory cytokine production across multiple pathogenic immune cell types, while preserving regulatory T cell numbers to maintain immune tolerance and provide a therapeutic window.[1][2][3][5] Preclinical studies have shown dose-dependent efficacy of a MALT1 inhibitor with the RHX-317 profile in validated models of cGVHD, rheumatoid arthritis, and lupus nephritis, and the program incorporates metabolite and metabolic pathway signatures to enable precision stratification of heterogeneous patient subsets in clinical development.[2][3][5][9]