Synthetic Design Lab, a next-generation antibody-drug conjugate (ADC) and protein engineering company, presented preclinical data in an oral presentation at the American Association for Cancer Research (AACR) Annual Meeting 2026 demonstrating that its proprietary SYNTHBODY™ therapeutic platform delivers log-order improvements in internalization, potency, and efficacy compared to current ADCs. The presentation marks the company's first public disclosure of platform and lead candidate data and introduces a new paradigm for ADC and biologic therapy design.

Where today's antibody-drug conjugates are limited by single- or bi-specific protein targeting, a SYNTHBODY™ therapeutic employs engineered design principles to achieve, in a combinatorial fashion, a multi-protein binding architecture and geometry that adjusts its binding and payload delivery to different cancer cell conformations and presentations. Unlike past approved protein therapeutics, which passively bind to a target and either inhibit or activate it, SYNTHBODY™ functions like a molecular processor, using built-in logic gates to adjust its behavior based on what it encounters in the body.

"The modern approach in drug development is the right drug for the right patient. Smart drugs capable of adjusting their own behavior may eventually upend that model entirely, because you may not need to match drug to patient when the drug itself can adapt," said Daniel S. Chen, M.D., Ph.D., founder and CEO of Synthetic Design Lab. "That type of inherent advanced drug intelligence has never existed in an approved medicine. Today's data are the first demonstration that it is possible."

That intelligence addresses one of the field’s most stubborn limitations: limited targets that are expressed specifically at high levels on cancer cells. ADCs such as trastuzumab deruxtecan (ENHERTU) have demonstrated that when therapeutic payloads are delivered to high expressing targets with precision and efficacy, metastatic HER2+ breast cancer can be treated with complete responses exceeding 20% and durability of response greater than 30 months. But HER2 is an outlier: its high specific expression levels on tumor cells are rarely replicated by other targets, leaving most cancers beyond the reach of current ADC approaches. SYNTHBODY™ was engineered to solve this problem by creating synthetic targeting equivalents, coordinating multiple lower-expression targets and higher-expression non-specific targets across a much wider range of tumors.

Data Highlights

Synthetic Design Lab presented data on a multiple myeloma-targeting SYNTHBODY™ that incorporates affinity- and geometry-tuned binders for BCMA, GPRC5D, and CD38 – three antigens that individually fall short of HER2-like expression and specificity. When combined in a properly designed SYNTHBODY™ architecture, it creates a synthetic high-expression high-specificity target through multi-layered logic-gating.

In head-to-head studies, the presented SYNTHBODY™ demonstrated more than 30x greater internalization versus the BCMA-targeting IgG antibody belantamab, and when bioconjugated to MMAF, achieved more than 80x greater potency versus belantamab mafodotin in human myeloma cells. The molecule retained its activity in cell lines with both high and low expression of each of its three targets and evaded clinically relevant concentrations of soluble BCMA, a known resistance mechanism that limits belantamab efficacy. The SYNTHBODY™ platform also demonstrated tunable IgG-like pharmacokinetics in vivo. In mouse tumor models, the molecule achieved ≥10x increased potency compared to an IgG-based comparator.

Similar early results were observed in a Non-Hodgkin's Lymphoma (NHL)-targeting SYNTHBODY™ construct, and a high-throughput SYNTHBODY ENGINE™ approach is being used to rapidly generate and optimize multiple solid tumor SYNTHBODY™ ADCs, supporting the platform's broad applicability across cancer types.

The SYNTHBODY™ architecture introduces something with no precedent in protein-based medicine: advanced logic-gated drug behavior. The constructs behave like molecular transistors, with "AND-BETTER" logic-gated control, layered with "AND" safety gates and "MULTIPLIER" functions that produce synergistic activity absent from conventional antibody ADCs. Optimized SYNTHBODY™ constructs also demonstrate strong manufacturability in CHO cells, favorable developability, and tunable IgG-like pharmacokinetics in vivo.

"Our platform is a fundamentally different way of thinking about how to target a cancer cell," said Ramesh Baliga, Ph.D., Chief Scientific Officer and co-founder of Synthetic Design Lab. "By controlling the geometry and biophysics of the targeting architecture itself, we can generate capabilities and emergent properties that simply aren't possible with conventional IgG-based formats."