Next-Generation Nanobody Therapeutic Targeting ALB and CTLA4 Pathways for Cancer Immunotherapy
VHH-P747 is a humanized nanobody designed to target albumin (ALB) and cytotoxic T-lymphocyte associated protein 4 (CTLA4), two critical proteins implicated in cancer development and progression. Currently in the Biological Testing phase, VHH-P747 integrates advanced half-life extension and multivalent binding strategies to enhance therapeutic efficacy. By engaging both ALB and CTLA4, this nanobody offers a unique immunotherapeutic approach for cancer treatment, aiming to improve patient outcomes through dual targeting mechanisms. The development of VHH-P747 underscores a commitment to innovative antibody engineering for difficult-to-treat cancers.
| Candidate | VHH-P747 |
| Target | albumin (ALB) cytotoxic T-lymphocyte associated protein 4 (CTLA4) |
| Modality | humanized bispecific VHH |
| Indication | Cancer |
Licensing Opportunity
VHH-P747 is available for out-licensing. We welcome collaboration and partnership discussions with biopharmaceutical companies interested in advancing next-generation immunotherapeutics for cancer.
Contact UsDevelopment Phase
| Program | Research | Preclinical | Phase 1 |
|---|---|---|---|
| VHH-P747 |
Modality
VHH-P747 utilizes a half-life extended, multivalent immunoglobulin single-domain antibody format. Its modular architecture comprises a single-domain antibody engineered for high affinity and specificity, targeting three discrete epitopes on CTLA4. These domains are connected via a flexible (G4S)x7 linker to an ISVD specific for ALB, which facilitates binding to human serum albumin. This design dramatically enhances the molecule’s serum stability and in vivo persistence, key for maximizing therapeutic window in cancer applications. The small molecular size of the nanobody enables superior tissue penetration and access to tumor microenvironments, while multivalency augments functional avidity and therapeutic impact.
Target
ALB and CTLA4 represent two strategic molecular targets in cancer immunotherapy. ALB, a major plasma protein, is involved in maintaining oncotic pressure and drug pharmacokinetics, with primary expression in hepatic tissues and circulating in the bloodstream. Targeting ALB benefits drug half-life extension and systemic stability. CTLA4, an immune checkpoint molecule predominantly expressed on regulatory and activated T cells, downmodulates immune responses and is a key negative regulator during T cell activation. Inhibiting CTLA4 unleashes anti-tumor immunity, enhancing T cell–mediated cytotoxicity against cancer cells. VHH-P747’s ability to simultaneously bind ALB and CTLA4 enables a dual-function strategy: improved bioavailability through ALB binding and immune modulation via CTLA4 blockade, creating a highly attractive asset for oncology pipelines.
Mechanism of Action
The mechanism of action of VHH-P747 is based on dual targeting of ALB and CTLA4. Through high-affinity binding to ALB, the nanobody benefits from extended serum half-life, facilitating sustained therapeutic exposure. Simultaneously, VHH-P747 binds to CTLA4 with mutivalent domains, effectively inhibiting this immune checkpoint. By blocking CTLA4-mediated signaling, the nanobody lifts the inhibition on T cell activation, thereby amplifying anti-tumor immune responses within the cancer microenvironment. This modular nanobody platform also allows potential future adaptation for advanced therapeutic modalities, including antibody-drug conjugates (ADC) and multispecific constructs, broadening its clinical applicability.
Cancer
Cancer encompasses a diverse group of diseases characterized by the uncontrolled growth and spread of abnormal cells. It remains one of the leading causes of morbidity and mortality worldwide, with incidence and burden expected to increase in coming decades. Standard treatments include surgery, chemotherapy, radiation therapy, immunotherapy, and molecularly targeted agents. Despite advances, significant challenges persist due to tumor heterogeneity, resistance mechanisms, and adverse effects, leaving many patients with limited long-term benefit. Immunotherapies targeting checkpoint inhibitors like CTLA4 have ushered in a new era, yet not all patients achieve durable responses. The current clinical need is for therapies that combine robust efficacy with sustained systemic exposure and improved safety profiles. VHH-P747, by co-targeting ALB for half-life extension and CTLA4 for immune checkpoint blockade, holds promise to address these unmet needs and support improved clinical outcomes for patients battling cancer.