Next-Generation Bispecific Nanobody Targeting CD3 Complex and MAGEA4 for Advanced Lung Cancer Immunotherapy
VHH-P555 is a novel, humanized nanobody-based bispecific antibody targeting the CD3 Complex (T Cell Receptor Complex) and MAGE family member A4 (MAGEA4), expressed in human embryonic kidney 293 cells. Currently in the biological testing stage, this program is designed to harness new immunotherapeutic approaches against lung cancer. By redirecting T cells toward tumor cells expressing MAGEA4, VHH-P555 offers a differentiated strategy for precision-targeted intervention in lung cancer treatment. The dual specificity of VHH-P555 enables it to bridge immune effector cells and malignant cells, with the potential to address key challenges in current lung cancer therapies.
| Candidate | VHH-P555 |
| Target | CD3 Complex (T Cell Receptor Complex) MAGE family member A4 (MAGEA4) |
| Modality | humanized bispecific VHH |
| Indication | Lung Cancer |
Licensing Opportunity
VHH-P555 is available for out-licensing and partnership opportunities. We welcome engagement with industry partners seeking to advance innovative immunotherapies for lung cancer through joint development, licensing, or collaboration agreements.
Contact UsDevelopment Phase
| Program | Research | Preclinical | Phase 1 |
|---|---|---|---|
| VHH-P555 |
Modality
VHH-P555 is engineered as a bispecific antibody integrating a llama-derived single-domain nanobody specific for MAGEA4 peptide-MHC complex and a single-chain variable fragment (scFv) targeting CD3, produced in mammalian cells. This nanobody format, characterized by its single-domain structure and low molecular weight, delivers distinct pharmacokinetic and tissue-penetration advantages compared to conventional antibodies. The modularity and stability of VHH-P555 improve its tumor infiltration capability and may enhance target engagement in solid lung tumors, overcoming some limitations of larger antibody molecules. The humanized design supports improved tolerance and manufacturability, providing a promising platform for lung cancer therapy.
Target
CD3 Complex and MAGEA4 represent pivotal targets in lung cancer immunotherapy. CD3 Complex, a component of the T-cell receptor, is essential for T cell activation and primarily expressed on the surface of all mature T lymphocytes. MAGEA4 is a cancer-testis antigen from the MAGEA family and is frequently expressed in various malignancies, including lung cancer, but is largely absent in normal tissues except for immune-privileged sites. CD3 Complex mediates immune engagement, while MAGEA4 marks tumor cells for immune recognition. Their co-targeting by VHH-P555 leverages the cytolytic potential of T cells (via CD3 Complex) and the tumor specificity of MAGEA4. Strategic dual targeting of CD3 Complex and MAGEA4 positions VHH-P555 as a high-value asset for lung cancer drug development, enabling precision immunotherapy with minimized off-tumor activity.
Mechanism of Action
VHH-P555 binds selectively to MAGEA4-expressing tumor cells via its nanobody domain and simultaneously engages CD3 Complex on T cells through its scFv fragment. This bispecific mechanism recruits and activates T cells at the tumor site, leading to localized immune synapse formation, T cell activation, and targeted cytotoxicity against MAGEA4-positive cancer cells. As a T-cell engager, VHH-P555 modulates signal transduction pathways pivotal for immune response amplification. The nanobody platform underlying VHH-P555 enables potential development of advanced formats, such as antibody-drug conjugates (ADCs) and additional bispecific constructs, making it a promising component in next-generation immuno-oncology therapeutics.
Lung Cancer
Lung cancer remains one of the most diagnosed malignancies and leading causes of cancer mortality worldwide. The disease encompasses a heterogeneous group of tumors, with non-small cell lung cancer (NSCLC) being the predominant subtype. Current therapies include surgical resection, chemotherapy, radiotherapy, immunotherapy, and targeted treatments, yet five-year survival rates for advanced-stage patients remain low. Limitations of conventional therapies include high toxicity, limited durability of response, and the frequent emergence of resistance. There is a significant unmet medical need for innovative and more selective treatments. VHH-P555 represents a potential breakthrough by mobilizing the patient’s own T cells to selectively eradicate MAGEA4-expressing tumor cells, offering a promising therapeutic option for patients with refractory or relapsed lung cancer and those unresponsive to existing therapies.