Next-Generation Bispecific Nanobody Targeting EGFR and TNFRSF9 for Solid Tumor Therapy

VHH-P807 is a bispecific, humanized nanobody-based trimerbody currently in biological testing, designed to target both epidermal growth factor receptor (EGFR) and TNF receptor superfamily member 9 (TNFRSF9). This innovative antibody construct leverages advanced protein engineering to engage key immunoregulatory and tumor-associated pathways, offering a novel therapeutic strategy for the treatment of solid tumors. Combining the specificities for EGFR and TNFRSF9, VHH-P807 holds significant promise for addressing challenging oncology indications where dual targeting can enhance therapeutic potential and clinical outcomes.

Licensing Opportunity

VHH-P807 is available for out-licensing or collaborative development. We welcome inquiries from partners seeking to advance this differentiated bispecific nanobody for solid tumor indications.

Development Phase

Modality

VHH-P807 features a unique trimeric architecture consisting of three agonistic anti-TNFRSF9 single-chain fragments and three anti-EGFR single-domain antibodies. Each is fused to the N- and C-termini of a human collagen-derived trimerization domain, and the entire construct is expressed in Chinese hamster ovary cells. The single-domain antibody format confers VHH-P807 with small molecular size, increased stability, and superior tissue penetration compared to conventional antibodies. These structural attributes enhance its ability to access and accumulate within dense solid tumor microenvironments, providing improved efficacy and flexibility in therapeutic design.

Target

EGFR and TNFRSF9 are both clinically validated targets in oncology. EGFR is a transmembrane tyrosine kinase receptor involved in cell proliferation and survival and is frequently overexpressed in various epithelial cancers. TNFRSF9, a co-stimulatory molecule in the TNF receptor superfamily, is primarily expressed on activated T cells and natural killer cells, playing a vital role in immune activation and anti-tumor responses. In solid tumors, overexpression of EGFR contributes to cancer progression, while stimulation of TNFRSF9 can enhance the cytotoxic capacity of immune effector cells. The strategic dual targeting of EGFR and TNFRSF9 by VHH-P807 provides an opportunity to simultaneously block tumor growth signaling and potentiate anti-tumor immunity, representing a valuable asset in advanced solid tumor development pipelines.

Mechanism of Action

VHH-P807 exerts its activity by binding to EGFR on tumor cells and engaging TNFRSF9 on immune cells. Through antagonizing EGFR signaling, it impedes downstream proliferative and survival pathways in cancer cells. Concurrently, VHH-P807 agonizes TNFRSF9, delivering a co-stimulatory signal that promotes activation and proliferation of T cells and natural killer cells within the tumor microenvironment. This dual mechanism not only inhibits tumor cell growth directly but also amplifies immune-mediated cytotoxicity. The nanobody scaffold and bispecific architecture allow expansion to other modalities, including antibody-drug conjugates and other bispecifics, enhancing its platform potential.

Solid Tumor

Solid tumors represent a diverse group of malignancies characterized by the uncontrolled proliferation of cells within solid organs or tissues. They are responsible for a substantial proportion of global cancer morbidity and mortality, affecting major anatomical sites such as the lung, breast, colon, and pancreas. Standard treatments include surgery, chemotherapy, radiotherapy, immunotherapy, and targeted therapies. Although targeted therapies and immunotherapies have transformed treatment paradigms, many patients with advanced or resistant disease remain with limited options due to tumor heterogeneity, immunosuppressive microenvironments, and acquired resistance. There is an urgent clinical need for more effective therapeutics capable of overcoming these barriers. By targeting both EGFR and TNFRSF9, VHH-P807 seeks to inhibit tumor growth signaling and activate robust anti-tumor immune responses, potentially addressing significant unmet needs in the solid tumor therapeutic landscape.