Key Takeaways:
Hansoh Pharmaceutical's B7-H3-targeted antibody-drug conjugate risvutatug rezetecan (HS-20093) met the primary endpoint of overall survival in a Phase 3 trial of patients with advanced or relapsed small-cell lung cancer, the company said July 10.
"This is the first positive Phase 3 overall survival data reported for a B7-H3-targeted ADC in any tumor type," Hesham Abdullah, senior vice president and global head of oncology R&D at GSK, said in a statement. GSK holds exclusive rights to the drug outside Greater China under a December 2023 deal that included $185 million upfront and up to $1.7 billion in milestones.
The open-label ARTEMIS-008 trial enrolled about 460 patients in China, randomizing them to receive either ris-rez or topotecan, the standard-of-care chemotherapy for relapsed SCLC. Besides the statistically significant OS improvement, the ADC showed consistent benefit across key secondary endpoints including progression-free survival, according to GSK. No new safety signals emerged, with the profile aligning with prior studies.
The result validates one of the largest China-biotech licensing pacts in oncology and positions Hansoh to file for regulatory approval in China. GSK is running its own global Phase 3 study, EMBOLD SCLC-301, in relapsed extensive-stage SCLC, with data expected by the end of 2027. The British pharma is also expanding ris-rez into other solid tumors, including gastrointestinal and genitourinary cancers.
Ris-rez has received breakthrough therapy designation from the US Food and Drug Administration and priority medicines designation from the European Medicines Agency for relapsed or refractory extensive-stage SCLC, plus orphan drug status in the US, EU and Japan.
Hansoh has emerged as one of China's most prolific dealmakers, signing six major out-licensing agreements since October 2023 with partners including GSK, Merck, Regeneron, Roche and Glenmark. The company's innovation drug and collaboration revenue reached 123.54 billion yuan ($17 billion) in 2025, accounting for 82.2 percent of total revenue.
The positive readout increases the probability that GSK will exercise its option to advance ris-rez globally and triggers milestone payments under the licensing agreement. Investors will watch for detailed efficacy data, including hazard ratios and median OS, expected at an upcoming medical conference.
This article is for informational purposes only and does not constitute investment advice.
