2025 mAbTalk Symposium – San Diego: Highlights and Event Recap

The 2025 mAbTalk Symposium by the Chinese Antibody Society was held in San Deigo, CA, on December 14, 2025. The event focused on “Novel Modalities in the Frontier of Antibody Therapeutics”, with 100+ attendees and 15+ sponsors in attendance. 

→ Biointron’s Highlighted Points:

1. Targeting Two Fronts: EpCAM × CD47 Bispecific Antibodies

Virtuoso Therapeutics introduced VP1186, a bispecific antibody targeting EpCAM and CD47 to address challenges in solid tumor immunotherapy. 

Key Concepts:

• EpCAM: Overexpressed on epithelial-derived tumors, enabling tumor targeting. 

• CD47: A “don’t eat me” signal inhibiting phagocytosis by macrophages. 

• VP1186 mechanism: 

• Directs immune cells (macrophages) to tumor cells via EpCAM. 

• Blocks CD47 to promote tumor cell engulfment. 

Implications for Biotech:

• Enhances tumor-specific immune activation. 

• Minimizes systemic toxicity seen with CD47 monotherapy. 

• Requires precision protein engineering, including: 

• Heterodimer design 

• Expression optimization 

• Scalable purification platforms 

Antibody Production →

2. Tumor-Activated Conditional T Cell Engagers

Amberstone Biosciences presented a conditional TCE platform engineered to selectively activate T cells only within tumor environments. 

Highlights:

• Logic-gated activation:

• Protease-dependent unmasking 

• pH-sensitive binding domains 

• Tumor-specific engagement reduces:

• On-target, off-tumor toxicity 

• Cytokine release syndrome (CRS) 

Development Considerations:

• High modularity allows rapid antigen swapping. 

• Expression and stability challenges require: 

• Customized vector design 

• Advanced in vitro screening 

• Pharmacokinetic fine-tuning 

Bispecific Antibody Expression →

3. Trispecific Antibodies for Cytokine Blockade in Allergy

Pfizer discussed the use of trispecific antibodies to simultaneously inhibit multiple allergy-related cytokines such as IL-4, IL-13, and IL-33. 

Therapeutic Rationale:

• Allergic conditions involve redundant cytokine signaling.

• Trispecifics may: 

• Enhance efficacy in refractory patients 

• Reduce dosing frequency 

• Improve tissue-specific control of inflammation 

Technical Challenges:

• Chain pairing control 

• Folding and stability of large constructs 

• Fc engineering for appropriate half-life and immune modulation

4. Immunotherapy Beyond Checkpoints: Immune Feedback Modulators 

Novel strategies to manipulate immune feedback loops for better therapeutic control in cancer and autoimmune diseases were discussed. 

Target Categories:

• Inhibitory receptors (beyond PD-1/CTLA-4) 

• Metabolic checkpoints (e.g., IDO1, arginase) 

• Cytokines regulating T cell tolerance or exhaustion 

Strategic Value:

• May enable selective immune reprogramming 

• Offers dual-use targets for oncology and immunology 

• Requires high-throughput single-cell profiling and functional screening 

5. Single-Domain Antibodies (sdAbs) and Modular Therapeutics

The utility of single-domain antibodies (sdAbs), also known as nanobodies, for advanced therapeutic applications were talked about. 

Benefits of sdAbs:

• Small size (~15 kDa) enables tumor and tissue penetration 

• High thermal stability 

• Binds to cryptic or concave epitopes 

• Ideal for:

• Bispecific/multispecific fusion 

• Intrabodies for intracellular targeting 

• Drug conjugates and diagnostics 

Manufacturing Implications:

• Can be produced in E. coli, but mammalian systems are preferred for therapeutic-grade material. 

• Facilitates scalable expression of modular constructs. 

Applications:

• Oncology

• Neurodegeneration 

• Infectious disease 

VHH Antibody Discovery →

Key Trends Shaping Antibody Therapeutics

The symposium highlighted several trends influencing antibody R&D and biomanufacturing strategies: 

• Multispecificity and Functional Modularity - Need for robust expression systems that support complex architectures and high-fidelity folding. 

• Conditional and Context-Specific Activation - Requires precise control of activation triggers, often relying on tumor protease expression or pH gradients. 

• Fc Engineering for Effector Modulation - Fc variant libraries and binding assays must be tightly integrated into antibody design workflows. 

• Immune System Rewiring in Autoimmunity and Oncology - Greater need for mechanistic validation and functional screening platforms early in the discovery process. 

• Next-Gen Formats: sdAbs and Intrabodies - Expression platforms must adapt to non-IgG scaffolds, fusion constructs, and non-traditional purification strategies. 

Thank you to everyone who visited our booth at the 2025 mAbTalk Symposium to learn about our services! We had a fantastic time chatting with you and how it can help you achieve antibody development. Our expert team would be happy to answer any follow-up questions. Feel free to email us at info@biointron.com or visit our website at www.biointron.com.