Olverembatinib (HQP1351) is well tolerated and shows antitumor activity in patients with tyrosine kinase inhibitor-resistant succinate dehydrogenase-deficient gastrointestinal stromal tumors (GISTs), according to results from a phase 1b/2 clinical trial.
Olverembatinib is a third-generation tyrosine kinase inhibitor by Ascentage Pharma and one of 5 of the company’s novel drug candidates, results of which were presented at the 2022 American Society of Clinical Oncology Annual Meeting.
“These results highlight the rapid progress in our drug discovery and clinical development, as well as our capability in global innovation,” Yifan Zhai MD, PhD, Ascentage Pharma’s chief medical officer said in a press release.
“We are now accelerating our clinical programs globally in the hope of benefitting more patients around the world.”
Read more about the etiology of GIST
During the olverembatinib trial, 39 patients with locally advanced or metastatic GISTs whose disease was resistant or failed to respond to imatinib or other tyrosine kinase inhibitors were given oral olverembatinib once every 2 days in 28-day repeated cycles. First, 3 patients were treated with 20 mg of olverembatinib, and then the remaining patients were randomized to receive 30 mg, 40 mg, and 50 mg of treatment.
Of the 39 patients, 8 had no mutation in the KIT proto-oncogene. Of these, 6 were succinate dehydrogenase-deficient. A total of 2 patients had a partial response to treatment with the tumor of one of them shrinking by 35.9% and that of the other shrinking by 54.2% at the first evaluation. For half of the 8 patients, the best response was stable disease.
The remaining 31 patients had a mutation in the KIT proto-oncogene or in the PDGFRA gene. Of these, 13 had stable disease for at least 2 cycles of treatment with olverembatinib as the best response. However, the disease of 10 of them progressed before the third cycle of treatment. Eight patients withdrew early from the study.
Almost all patients (92.3%) experienced treatment-emergent adverse events during the trial. However, most of these were either mild or moderate. They included increased leukocyte and neutrophil counts, anemia, constipation or asthenia, hyperuricemia, hypoalbuminemia, and elevated aspartate aminotransferase or alanine transaminase levels.
ASCO 2022 | Ascentage Pharma presents updated results from multiple clinical studies demonstrating rapid progress in global clinical development. News release. Ascentage Pharma; May 26, 2022.