Hansoh Pharma and GSK’s risvutatug rezetecan (Ris‑Rez/HS‑20093) delivers the first Phase III overall survival benefit for a B7‑H3‑targeted ADC in relapsed small‑cell lung cancer, meeting the primary endpoint in ARTEMIS‑008 and supporting regulatory filing in China.
Written By: Chikkula Pavan Kumar, PharmD
Reviewed By: Pharmacally Editorial Team
Small-cell lung cancer (SCLC) may soon gain a new treatment option after Hansoh Pharmaceutical Group and its global licensing partner GSK reported positive Phase III results for risvutatug rezetecan (Ris-Rez/HS-20093) in patients with advanced or relapsed disease. The pivotal ARTEMIS-008 study (NCT06498479) met its primary endpoint, demonstrating statistically significant and clinically meaningful improvements in overall survival (OS) compared with topotecan, the current standard second-line therapy. The findings represent the first positive Phase III trial to demonstrate an overall survival benefit for a B7-H3-targeted antibody-drug conjugate (ADC) in any tumour type.
Phase III ARTEMIS-008 Demonstrates Survival Benefit Over Topotecan
ARTEMIS-008 is a randomized, multicenter, open-label Phase III trial conducted in China that enrolled approximately 460 patients with advanced or relapsed SCLC whose disease progressed after platinum-based chemotherapy. Patients received either risvutatug rezetecan or topotecan, the long-established standard treatment for relapsed SCLC despite historically providing a median overall survival of only about six to eight months.
At a pre-specified interim analysis, risvutatug rezetecan achieved statistically significant and clinically meaningful improvements in overall survival compared with topotecan. Consistent benefit was also observed across key secondary endpoints, including progression-free survival (PFS). Although detailed efficacy data, including hazard ratios and confidence intervals, have not yet been released, both Hansoh Pharma and GSK confirmed that the primary endpoint was successfully met. The safety profile remained consistent with previous studies, and investigators reported no new safety signals.
Relapsed Small-Cell Lung Cancer Has Few Effective Treatment Options
SCLC accounts for approximately 15% of all lung cancers but remains one of the most aggressive malignancies. While platinum-based chemotherapy produces high initial response rates, most patients relapse rapidly or develop treatment resistance. Once relapse occurs, treatment options are limited and survival outcomes remain poor, highlighting the need for more effective second-line therapies.
How Risvutatug Rezetecan Targets B7-H3
Risvutatug rezetecan is an investigational B7-H3-targeted ADC comprising a fully human anti-B7-H3 monoclonal antibody linked through a cleavable tetrapeptide linker to a topoisomerase I inhibitor payload. Because B7-H3 is highly expressed on SCLC and several other solid tumours, the therapy delivers its cytotoxic payload directly into tumour cells while limiting systemic exposure.
The therapy has received multiple regulatory designations, including Breakthrough Therapy and Orphan Drug Designations from the U.S. Food and Drug Administration for relapsed or refractory extensive-stage SCLC, Priority Medicines (PRIME) designation from the European Medicines Agency, orphan designation in Europe for pulmonary neuroendocrine carcinoma, and orphan drug designation in Japan.
GSK Sees Broader Potential for B7-H3-Directed Therapy
Hesham Abdullah, Senior Vice President and Global Head of Oncology, R&D at GSK, said the Phase III results mark an important milestone for B7-H3-targeted therapies. He noted that the survival benefit, together with previously generated clinical evidence, strengthens support for B7-H3 as a therapeutic target across luuyng cancer and other solid tumours and reinforces continued development of risvutatug rezetecan in areas of high unmet medical need.
Advancing the Treatment Landscape for Relapsed SCLC
Hansoh Pharma plans to present the complete ARTEMIS-008 results at an upcoming international oncology congress and initiate discussions with the China National Medical Products Administration (NMPA) Center for Drug Evaluation (CDE) to support a future Biologics License Application (BLA).
Outside mainland China, Hong Kong, Macau and Taiwan, GSK holds exclusive rights to develop and commercialize risvutatug rezetecan under a licensing agreement signed in December 2023. The company is advancing a broad global clinical development programme across lung cancer, prostate cancer and other solid tumours.
A key component of that programme is the global Phase III EMBOLD SCLC-301 trial (NCT07099898), evaluating risvutatug rezetecan in patients with relapsed extensive-stage SCLC. Pivotal data are expected next year and will help determine whether the survival benefit observed in ARTEMIS-008 can be reproduced in a global patient population. If successful, the programme could establish the first B7-H3-targeted ADC to improve overall survival in relapsed SCLC and potentially redefine the second-line treatment landscape for this aggressive disease.
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About the Writer
Chikkula Pavan Kumar (LinkedIn), PharmD is a Doctor of Pharmacy with a keen interest in clinical pharmacy, pharmacovigilance, and evidence-based practice. In his words, he is passionate about patient safety and translating complex medical information into clear, research-driven communication.