Earendil Labs signed a licensing and development agreement with WuXi XDC to access payload‑linker technology and end‑to‑end CRDMO services for antibody‑drug conjugates, in a deal valued at up to approximately $885 million. WuXi XDC will support CMC development and manufacturing via its WuXiTecan‑2 platform; Earendil will handle product development, regulatory submissions and commercialization. The agreement complements Earendil’s prior partnerships with Sanofi and underscores the continued strategic value of payload‑linker platforms in accelerating ADC R&D. Both companies highlighted the alliance’s potential to produce next‑generation ADCs with improved safety and efficacy profiles.