Rigel’s investigational candidate, R552, is an orally available, potent and selective inhibitor of receptor-interacting protein kinase (RIP1).
RIP1 is implicated in a broad range of key inflammatory cellular processes including necroptosis, a type of regulated cell death, and cytokine production. In necroptosis, cells rupture leading to the dispersion of cell contents, which can trigger an immune response and enhance inflammation. In preclinical studies, R552 showed prevention of joint and skin inflammation in a RIP1-mediated murine model of inflammation and tissue damage.
Development of R552:
- Completed the single ascending dose portion of a Phase 1 study