While ESMO 2023 is just around the corner, the leading player in the Pharma industry including AstraZeneca, Novartis, Hansoh BioMedical and Eli Lilly, etc. are all geared up for this conference to present the data readouts and final analysis. This content summarizes Hansoh BioMedical's HS-20089, a novel DAR-6 antibody-drug conjugate (ADC), based on results from its First-in-human/Phase I trial.

HR+/HER2– Breast Cancer Highlights

• Abstract Number – #381O
• Abstract Type - Proffered Paper Session
• Indication – Advanced solid tumors
• Target – ADC targeting B7-H4

B7-H4, a transmembrane glycoprotein belonging to the B7 superfamily, exhibits minimal expression in healthy tissues but is markedly heightened in various cancer types. Hansoh BioMedical's novel drug, HS-20089, is an antibody-drug conjugate (ADC) tailored to target B7-H4, featuring a 6:1 drug-to-antibody ratio. The company launched a groundbreaking Phase I trial to assess HS-20089's safety, tolerability, pharmacokinetics, and efficacy in patients with advanced solid tumors unresponsive to standard treatments. As of April 2023, among 33 patients assessed, 8 displayed partial responses (PRs) to HS-20089, yielding a 24.2% response rate, comprising 3 confirmed PRs and 5 PRs pending final confirmation. The comprehensive disease control rate achieved 63.6%. The ongoing study suggests HS-20089's well-tolerance and anti-tumor potential in advanced solid tumors, particularly showcasing promising clinical effectiveness in triple-negative breast cancer (TNBC).

Preclinical experiments demonstrated the inhibition of tumor cell growth expressing B7-H4 both in vitro and in vivo. Numerous solid cancers, including breast and ovarian cancer, exhibit elevated B7-H4 expression. The promising clinical efficacy of HS-20089 in treating triple-negative breast cancer (TNBC) underscores its potential as a groundbreaking therapy for advanced breast cancer