Main Conference Day 3 - 2026Friday, 29 May 2026 - European Time GMT+1

T cell engagers (TCEs) show promise in solid tumors but are constrained by cytokine release and on-target, off-tumor toxicity. Amberstone’s T-MATE™ platform overcomes these barriers with a pH-gated, target-selective mechanism that adapts to tumor pH heterogeneity while maintaining an optimal therapeutic profile. This conditional strategy enables a new generation of TCEs that combines both safety and efficacy with broad applicability across diverse solid tumor indications.

Systemic toxicities from target expression on healthy tissues limit cancer therapy. The PrimeBody platform uses protease-cleavable linkers and affinity-tuned masking to create tumor-activated biologics with high systemic stability and efficient tumor activation. VOR-101, a masked Fc-enhanced CD47 blocker, remains inert in circulation but activates in tumors, achieving ~1000-fold selectivity and ~100-fold higher exposure without added toxicity. This drives durable regressions and an improved therapeutic index. Applications to cytokines and TCEs will also be presented.

PRO-XTEN™ masked T cell engagers (TCEs) are conditionally activated immune therapeutics designed to exploit dysregulated protease activity within the tumor microenvironment. This approach enables tumor-selective TCE activation while minimizing systemic toxicity. The XTEN mask serves a dual function: masking TCE activity and extending the half-life of the masked molecule, while the proteolytically activated TCE exhibits a short half-life, creating conditional pharmacokinetics that enhance tumor exposure while limiting systemic active drug circulation. Preclinical studies demonstrated: (1) robust masking with ~10,000-fold reduction in cytotoxicity in vitro; (2) potent anti-tumor efficacy in vivo at doses comparable to unmasked TCE controls; and (3) >100-fold improvement in maximum tolerated dose (MTD) in non-human primates. These findings support a significantly enhanced therapeutic window through tumor-specific activation and conditional PK. Clinical trials evaluating PRO-XTEN™ TCEs targeting HER2, PSMA, and EGFR are currently underway, with early data demonstrating the translational potential of this protease-activated platform.