Next-Generation Nanobody Therapeutics Targeting ALB and LAG3 for Innovative Cancer Immunotherapy

VHH-P708 is a fully humanized nanobody construct designed to target both albumin (ALB) and lymphocyte activating 3 (LAG3), currently in the Biological Testing stage. By engaging albumin (ALB) and lymphocyte activating 3 (LAG3), VHH-P708 is positioned as a promising agent for the treatment of cancer. This program leverages precision molecular targeting to combine immune checkpoint modulation with pharmacokinetic enhancement, aiming to address unmet needs in oncology. The unique multivalent nanobody architecture has the potential to provide improved tumor targeting and immune system activation for enhanced therapeutic benefit in cancer patients.

Licensing Opportunity

VHH-P708 is available for out-licensing and strategic partnership opportunities. We welcome inquiries from collaborators and industry partners interested in advancing this innovative nanobody program for cancer immunotherapy.

Development Phase

Modality

VHH-P708 employs a cutting-edge nanobody modality composed of a half-life extended, multivalent immunoglobulin single variable domain (ISVD) format. This construct fuses an ISVD targeting human LAG3 with an ISVD targeting human ALB via a 35-amino acid glycine-serine linker, resulting in a highly stable, low molecular weight antibody fragment. The compact and modular structure of nanobodies enables superior tissue penetration, especially into solid tumors, and the fusion to ALB enhances serum half-life, supporting sustained therapeutic action. This innovative modality combines the advantages of nanobody stability, rapid production, and immune checkpoint inhibition, making it especially well-suited for tackling the complex tumor microenvironment in cancer.

Target

ALB and LAG3 are two essential molecular targets in the context of cancer therapy. ALB is a highly abundant plasma protein involved in transport and pharmacokinetics, primarily found in the bloodstream and extracellular spaces. The nanobody's engagement with ALB allows for prolonged circulation and optimized drug delivery profiles. LAG3, a transmembrane protein mainly expressed on activated T cells, functions as an immune checkpoint limiting T-cell activation and responses. In cancer, upregulation of LAG3 is associated with immune escape, making it a validated target for restoring anti-tumor immunity. Simultaneously targeting ALB and LAG3 provides a strong strategic advantage; ALB ensures enhanced bioavailability, while LAG3 inhibition has the potential to unlock robust anti-tumor immune responses. Thus, VHH-P708’s dual targeting approach uniquely positions it in the evolving cancer immunotherapy landscape by maximizing the benefits of both targets.

Mechanism of Action

VHH-P708 is engineered to engage both ALB and LAG3 through its nanobody components. By binding ALB, VHH-P708 links to the endogenous albumin pathway, which significantly extends its systemic half-life and bioavailability—a pharmacological advantage for durable cancer therapy. The anti-LAG3 domain of VHH-P708 acts as an immune checkpoint inhibitor by blocking LAG3-mediated suppression of T-cell activation, thereby promoting a revitalized anti-tumor immune response. The modular design of this nanobody construct also holds future potential for further platform expansion, including linkage with cytotoxic payloads (ADC) or combination with other immune effector molecules, enabling versatile therapeutic formats tailored to various cancer settings.

Cancer

Cancer encompasses a broad group of diseases characterized by abnormal cell growth and the potential to invade or spread to distant body sites. It remains a global health challenge, affecting millions of individuals and representing a leading cause of morbidity and mortality worldwide. Current treatment approaches include surgery, radiotherapy, chemotherapy, immunotherapy, and targeted biological agents. While immunotherapy and targeted treatments have made significant advances, many cancers remain refractory to standard intervention, with issues such as drug resistance, tumor heterogeneity, and immune evasion limiting long-term benefits. There is a clear unmet need for innovative therapies capable of enhancing efficacy, safety, and patient quality of life. VHH-P708, by integrating immune checkpoint inhibition with extended pharmacokinetics via ALB binding, offers a novel therapeutic strategy with the potential to improve outcomes for patients with challenging or relapsed cancers.