XYD-295

XYD-295 is a next-generation antibody-drug conjugate (ADC) linker-payload system developed by 1FDC Biotech and Beijing Hanmi Pharmaceutical. It utilizes a novel hydrophilic, site-specific linker technology designed to enhance the stability and pharmacokinetic profile of ADCs while reducing aggregation. XYD-295 specifically incorporates a topoisomerase I (TOP1) inhibitor as its therapeutic payload. Preclinical studies presented at AACR 2026 indicate that ADCs built with the XYD-295 system demonstrate superior plasma stability and potent anti-tumor activity across multiple targets, including DLL3, PD-L1, ADAM9, B7H3, EGFR, and cMET. The platform also supports the creation of dual-payload ADCs when used in conjunction with other modules like XYD-338.