*This is an investigational compound and has not been approved. Its safety and efficacy have not been established.

Our CD137xFAP bispecific antibody (bsAb) is undergoing clinical investigation as a monotherapy and in combination with a PD-1 inhibitor (ezabenlimab [BI 754091]* or pembrolizumab) for the treatment of patients with metastatic or unresectable recurrent head and neck squamous cell carcinoma (HNSCC).^1–3

CD137xFAP bsAb clinical trial

CD137xFAP bsAb mechanism of action

Our CD137xFAP bsAb is designed to selectively reactivate T-cells within the tumor microenvironment via concomitant binding to FAP on cancer-associated fibroblasts (CAFs) and CD137 on T-cells, potentially avoiding systemic activation of T-cells and associated cytotoxicity.^1,2,4–5

CD137xFAP bsAb mechanism of action¹

Combination therapy

The combination with a PD-1 inhibitor may boost tumor-specific T-cell activity further by both counteracting tumor-mediated suppression of T-cells and simultaneously activating the T-cells through CD137 agonism.^3,4

CD137, also known as 4-1BB, is a receptor expressed on immune cells such as T-cells, NK cells, and dendritic cells that functions as an important regulator of immune responses, and is an essential pathway for maximal CD4 and CD8 T-cell responses.⁵ FAP is a protein expressed on cancer-associated fibroblasts (CAFs).⁴

bsAb, bispecific antibody; CAF, cancer-associated fibroblast; CD, cluster of differentiation; FAP, fibroblast activation protein; HNSCC, head and neck squamous cell carcinoma; NK, natural killer; PD-1, programmed cell death protein-1.