Glossary
Objective Response Rate (ORR): The percentage of patients whose cancer shrinks or disappears after treatment.
Clinical Benefit Rate (CBR): The percentage of patients who get meaningful benefit from a treatment.
Progression-Free Survival (PFS): The length of time during and after treatment that a patient lives without the cancer growing or spreading.
“SDH-deficient GIST is an extremely rare tumor type that lacks high-quality, prospective clinical data; and in Chinese and international clinical guidelines, there are currently no recommended treatments for unresectable SDH-deficient GIST,” said professor Ruihua Xu, Academician of the Chinese Academy of Engineering, president and director of Sun Yat-sen University Cancer Center. “This phase 1 study has yielded encouraging efficacy and safety results, suggesting that olverembatinib may offer a new treatment option for this indication.”
Xu co-led the study of olverembatinib in this patient population, which evaluated the safety and antitumor activity of the drug among 66 patients with unresectable/metastatic GIST/other solid tumors, including 26 patients with SDH-deficient GIST who had failed prior treatment with tyrosine kinase inhibitors; this is, according to the news release, the largest prospective clinical trial in this rare subtype of GIST to date.
Among the 26 patients in the study with SDH-deficient GIST, the objective response rate was 23.1%, the clinical benefit rate was 84.6% and the median progression-free survival time was 25.7 months, at a median follow-up of 14.5 months.
“SDH-deficient GIST represents a treatment gap that urgently needs new treatment options. It took us approximately 5 years to enroll 26 patients in this study, which is now the world’s largest prospective clinical trial in SDH-deficient GIST,” said Professor Haibo Qiu, of Sun Yat-sen University Cancer Center, in a statement in the news release. “In the study, olverembatinib demonstrated impressive clinical benefits, including a median PFS of 25.7 months, as well as favorable safety and tolerability profiles. We will continue additional studies to validate the drug’s efficacy and safety in patients with SDH-deficient GIST.”
Dr. Yifan Zhai, chief medical officer of Ascentage Pharma, in a statement included in the news release, said: “We are very encouraged by these results, as they signal a potential breakthrough in addressing an indication with urgent unmet clinical need. Remaining committed to our mission of addressing unmet clinical needs in China and around the world, we will press forward with this clinical development program to bring a safe and effective new treatment option to patients as soon as possible.”
References
- “Ascentage Pharma Announces Publication of Olverembatinib Phase Ib Safety, Efficacy and Novel Mechanism Data in Gastrointestinal Stromal Tumors in Nature’s Signal Transduction and Targeted Therapy,” by Ascentage Pharma Group International Inc. News release; Nov. 24, 2025.
- “Gastrointestinal Stromal Tumor,” by the National Cancer Institute. https://www.cancer.gov/publications/dictionaries/cancer-terms/def/gastrointestinal-stromal-tumor.
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