Hansoh Pharma Submits Marketing Application in China for B7-H3 ADC Risvutatug Rezetecan in Platinum-Refractory Small Cell Lung Cancer

Hansoh Pharmaceutical Group Company Limited has submitted a marketing application in China for risvutatug rezetecan, its B7-H3 antibody-drug conjugate, for the treatment of platinum-refractory small cell lung cancer, according to the Center for Drug Evaluation website on September 2.

The filing marks a significant milestone for the drug, which carries the development code HS-20093. Risvutatug rezetecan is a fully human B7-H3 monoclonal antibody covalently linked to a topoisomerase inhibitor payload, representing Hansoh's proprietary approach to targeting this emerging cancer antigen.

In December 2023, Hansoh granted GlaxoSmithKline PLC an exclusive license to develop, manufacture, and commercialize the drug worldwide, excluding mainland China, Hong Kong, Macau, and Taiwan. GSK is currently advancing Phase III clinical trials overseas.

The regulatory submission follows positive results from the Phase III ARTEMIS-008 study, announced on July 10. The trial met its primary endpoint of overall survival, demonstrating a statistically significant and clinically meaningful improvement compared to topotecan, the standard second-line treatment for small cell lung cancer. Secondary endpoints, including progression-free survival, also showed consistent benefit. The safety profile remained consistent with prior studies, with no new safety signals identified.

The ARTEMIS-008 results represent the first positive Phase III data showing that a B7-H3 ADC can deliver a significant overall survival benefit in oncology, according to the company.

Small cell lung cancer accounts for approximately 15% of all lung cancers and is the most aggressive subtype, characterized by high malignancy, rapid disease progression, high relapse rates, and very poor prognosis. While platinum-based chemotherapy remains the standard first-line treatment, most patients relapse or develop resistance shortly after initial therapy, leaving very limited options in the second-line setting and beyond. The disease represents a significant unmet medical need.