Next-Generation Bispecific Nanobody Therapeutic Targeting CD47 and TACSTD2 for Breast Cancer Innovation

VHH-P295 is a humanized bispecific nanobody-based antibody currently in the Biological Testing stage, designed to target both the CD47 molecule (CD47) and the tumor associated calcium signal transducer 2 (TACSTD2). This advanced therapeutic candidate leverages the high specificity and affinity of single-domain antibodies to engage two clinically validated cell surface markers involved in breast cancer progression. By simultaneously addressing CD47 and TACSTD2, VHH-P295 holds significant potential to improve outcomes in breast cancer therapy, providing a novel approach to overcome key mechanisms of resistance and immune evasion in this disease.

Licensing Opportunity

VHH-P295 is available for out-licensing and partnership opportunities. We welcome inquiries from pharmaceutical and biotechnology companies interested in co-development, commercialization, or regional licensing to accelerate the advancement of this innovative therapeutic.

Development Phase

Modality

VHH-P295 employs a bispecific modality, comprising a single-domain antibody (sdAb) specific to TACSTD2, an sdAb targeting CD47, and a human IgG1 Fc domain, all fused in tandem. This engineered nanobody format combines the compact structure, high binding specificity, and excellent tissue penetration of sdAbs with the effector function and stability of a full-length antibody Fc region. The small molecular size of the nanobody components enables enhanced tumor infiltration and rapid systemic distribution, which are particularly valuable in targeting heterogeneous and densely stromalized breast cancer tissues. The modality design is anticipated to offer superior manufacturability and versatility for future combinatory and next-generation therapeutic applications.

Target

CD47 and TACSTD2 are transmembrane proteins implicated in tumor growth, metastasis, and immune evasion. CD47, expressed on a wide range of cells including tumor cells, functions to inhibit phagocytosis by interacting with signal regulatory protein alpha (SIRPα) on macrophages, thus known as the "don't eat me" signal. TACSTD2 is a cell surface glycoprotein highly expressed in various epithelial cancers, including breast cancer, and is associated with cell proliferation, migration, and poor prognosis. Both CD47 and TACSTD2 are differentially overexpressed in breast cancer tissues compared to normal tissues, making them attractive dual targets for therapeutic intervention. By simultaneously targeting CD47 and TACSTD2, VHH-P295 addresses multiple hallmarks of breast cancer pathogenesis and offers a strategic advantage in overcoming tumor immune escape and therapeutic resistance, underpinning its strong potential in clinical and commercial settings.

Mechanism of Action

VHH-P295 functions as a bispecific immune checkpoint inhibitor by binding to CD47 and TACSTD2 on the surface of breast cancer cells. Through specific engagement with CD47, VHH-P295 disrupts its interaction with SIRPα, effectively reversing the inhibitory signal and restoring macrophage-mediated phagocytosis of tumor cells. Simultaneous targeting of TACSTD2 further enhances antitumor activity by interfering with cell adhesion, migration, and growth signaling pathways central to breast cancer malignancy. The nanobody platform of VHH-P295 allows for additional engineering, offering avenues for conjugation with cytotoxic payloads (ADC) or the design of multispecific therapeutic architectures. This multifaceted mechanism is designed to induce robust antitumor immune responses and address both primary tumor growth and metastasis.

Breast Cancer

Breast cancer remains one of the most prevalent and heterogeneous malignancies affecting women worldwide. It encompasses a diverse group of subtypes, each characterized by distinct molecular features and responses to therapy. Standard treatment approaches include surgery, radiation, chemotherapy, hormonal therapy, and targeted therapy, often used in combination to reduce recurrence and improve survival. However, challenges such as the emergence of drug resistance, tumor immune evasion, and the limited effectiveness of single-agent immunotherapies persist, leaving significant unmet medical needs. Current therapies may not effectively address the intratumoral heterogeneity and complex microenvironment that contribute to treatment failure and disease progression. VHH-P295, with its bispecific targeting of CD47 and TACSTD2, introduces a promising immunotherapeutic strategy to counteract these issues. By addressing key immune checkpoint and tumor cell signaling pathways simultaneously, VHH-P295 holds potential to improve response rates, overcome mechanisms of resistance, and deliver durable benefits for patients with breast cancer.