Definition

An immunotherapeutic agent that targets both CD19 and 4-1BB (CDG5:I9necrosis factor receptor superfamily member 9; TNFRSF9), with potential immunostimulatory and antineoplastic activity. Upon administration, CD19-targeted 4-1BB ligand RO7227166 simultaneously binds to CD19 and 4-1BB, thereby crosslinking CD19 and 4-1BB positive cells. This triggers, through the 4-1BB ligand, the proliferation and activation of natural killer cells (NKs) and T cells. This results in an enhanced cytotoxic T-lymphocyte (CTL)-mediated immune response against CD19-expressing tumor cells. 4-1BB, a surface glycoprotein of the tumor necrosis factor receptor superfamily (TNFRSF), is an inducible costimulatory receptor that plays a key role in T-cell proliferation, survival and cytolytic activity.