SYN429

SYN429 is a synthetic type I interferon (IFN) partial agonist developed by IntegerBio. It is designed as a bispecific molecule that engages both IFNAR1 and IFNAR2 to enable tunable activation of the type I IFN pathway. Unlike traditional IFN-α, SYN429 is engineered to maintain potent anti-tumor activity—including the activation of antigen-presenting cells (APCs), promotion of T cell priming, and induction of PD-L1—while exhibiting a reduced induction of inflammatory cytokines associated with cytokine release syndrome (CRS). Preclinical data demonstrate that SYN429 can act as a monotherapy or synergize with immune checkpoint inhibitors (ICIs) to enhance tumor growth inhibition and induce durable anti-tumor immunity.