BYON4228 + pembrolizumab

BYON4228 + pembrolizumab is an investigational **combination therapy** currently in Phase 1 clinical trials for advanced or metastatic solid tumors. BYON4228 is a humanized monoclonal antibody that selectively targets **signal regulatory protein alpha (SIRPα)**, a checkpoint molecule primarily expressed on myeloid cells. BYON4228 blocks the **CD47-SIRPα axis**, a pathway exploited by tumors to inhibit innate immune cell activation and evade immune-mediated destruction. Its selectivity avoids cross-reactivity with SIRPγ on T-cells, preserving T-cell function and avoiding certain toxicities[3][8]. Pembrolizumab is a clinically approved monoclonal antibody targeting **programmed cell death protein 1 (PD-1)**, blocking the PD-1/PD-L1 axis and thus preventing tumor-induced inhibition of T-cell activity. The combination is intended to harness both innate and adaptive immunity, with BYON4228 enhancing the destruction of antibody-opsonized tumor cells while pembrolizumab reactivates T-cell anti-tumor responses[3][4][5]. Developer Byondis is conducting ongoing studies of BYON4228 both as monotherapy and combined with immune checkpoint inhibitors[1][2][3][4][5].

Brand names

Keytruda

Other names

BYON4228 + Keytruda