E-688

**E-688** is an investigational **B7-H3-targeted sialidase fusion protein** being developed by **Palleon Pharmaceuticals** in collaboration with **Henlius** for the treatment of **advanced or metastatic solid tumors**. Public disclosures describe E-688 as the same molecule as **HLX316**, a potential first-in-class glyco-immunology therapeutic that localizes **human sialidase** activity to **B7-H3-positive tumor cells** and the tumor microenvironment, enzymatically removing terminal sialic acids to reverse glycan-mediated immune suppression and enhance both innate and adaptive antitumor immunity. The program entered **Phase 1** clinical testing in China after IND clearance by the NMPA, with early development emphasizing solid tumors including platinum-resistant ovarian, primary peritoneal, and fallopian tube cancers.

Other names

B7-H3 targeting sialidase Fc fusion proteinB-7-H3 targeting sialidase Fc fusion proteinB 7-H3 targeting sialidase Fc fusion proteinhuman sialidase-armed anti-B7-H3 antibody