Akeso Clears Phase I Hurdle for B7-H3 ADC Targeting Solid Tumors

The new drug candidate targets B7-H3, a protein highly expressed across a spectrum of cancers including lung, prostate, and breast malignancies, while remaining largely absent in healthy tissues. Akeso intends to study AK157D1 both as a monotherapy and in combination with its existing bispecific antibodies, ivonescimab and cadonilimab.

This clearance represents the third next-generation ADC to move into clinical development for the Hong Kong-based firm, following the earlier advancement of its TROP2/Nectin-4 and HER3 candidates. By utilizing a proprietary maleimidocaproyl-alanine-alanine-alanine linker to attach a topoisomerase I inhibitor to the antibody, developers aim to bypass the hematologic toxicity and interstitial lung disease frequently associated with earlier, first-generation ADC treatments. The company continues to lean on its internal R&D platforms to refine these therapies, positioning them as potential cornerstones for future standard-of-care regimens in oncology.