Hansoh Pharmaceutical Group Co., Ltd. (Hansoh Pharma, 03692.HK) today announces that risvutatug rezetecan (Ris-Rez/HS-20093), the Group’s self-developed B7-H3 directed antibody-drug conjugate (ADC), met the primary endpoint of overall survival (OS) in a pivotal Phase 3 clinical trial (ARTEMIS-008) for patients with advanced or relapsed small cell lung cancer (SCLC) after prior platinum-based therapy. At a pre-specified interim analysis, Ris-Rez provided statistically significant and clinically meaningful OS improvements compared with topotecan. Consistent benefit was also observed across secondary clinical endpoints, including progression-free survival (PFS). The safety profile was consistent with prior findings, and no new safety signals were identified.

 

These results represent the first positive Phase III clinical trial to demonstrate an OS benefit for a B7-H3 directed ADC in any tumour type. Based on these findings, Hansoh Pharma will initiate communications with the National Medical Products Administration (NMPA) Center for Drug Evaluation (CDE) in China. in the near term to advance preparations for a Biologics License Application(BLA). Concurrently, the detailed data from ARTEMIS-008 study will be presented at an upcoming international oncology conference.

 

Breaking Through Treatment Bottlenecks in SCLC

SCLC[1] 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 a generally poor prognosis. Although platinum-based chemotherapy remains the standard first-line treatment for SCLC, the vast majority of patients experience rapid relapse or develop resistance post-treatment. With extremely limited options for second-line and subsequent therapies, a substantial unmet clinical need exists.

As a core ADC in Hansoh Pharma’s B7-H3 pipeline, Ris-Rez is designed to precisely target the B7-H3 antigen on the surface of tumor cells and deliver a topoisomerase inhibitor payload directly into the tumor cells. This directed approach aims to achieve potent tumor cell killing while significantly reducing systemic toxicity. The clinically meaningful improvement in OS and PFS demonstrated by Ris-Rez in the ARTEMIS-008 study, , conducted in SCLC patients who failed platinum-based therapy, may support a novel treatment strategy in this highly refractory tumor type.