Rigel’s investigational candidates are orally available, potent and selective inhibitors of receptor-interacting serine/threonine-protein kinase 1 (RIPK1).

RIPK1 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.

Rigel’s RIPK1 inhibitor program includes R552, its lead systemic molecule, and brain penetrating RIPK1 inhibitors for central nervous system (CNS) diseases.

Development of R552 (Systemic):

  • Completed Phase 1 study
  • Planned Phase 2 study to begin in 2021

Development of Rxxx (CNS Penetrant):

  • Currently in preclinical studies