Bridging Study Finds Ripretinib Improves Survival Among Chinese Patients With Advanced Gastrointestinal Stromal Tumors

Ripretinib improved clinical outcomes for Chinese patients with advanced gastrointestinal stromal tumors (GIST) in the fourth or later line of treatment, according to recent trial findings.

The phase 2, open-label study enrolled 39 patients with GIST across 9 centers in China between April 2020 and August 2020. All patients showed disease progression with, or intolerance to, three or more prior kinase inhibitors (imatinib, sunitinib, and at least one other drug). Treatment consisted of ripretinib 150 mg once daily in 28-day cycles until progressive disease, intolerable toxicity, or patient request of withdrawal. This study was designed as a bridging study of the phase 3 INVICTUS study, assessing the consistency of the data of Chinese patients with the global population. The primary outcome of the study was progression-free survival as determined by independent radiologic review. Secondary outcomes included objective response rate and safety.

At the primary data cutoff date of February 26, 2021, the median progression-free survival was 7.2 months (90% confidence interval 2.9 to 7.3). Study authors added that “the lower bound of the 90% CI exceeded 1 month, fulfilling the standard of bridging success.” The objective response rate was 18.4% (95% confidence interval 7.7% to 34.3%). There were treatment-related treatment-emergent adverse events in 94.9% of patients, with a majority reported as grade 1/2. There were grade 3/4 treatment-related adverse events in 15.4% of patients. Severe treatment-related adverse events were reported in 5.1% of the patients. There were no treatment-related adverse events which led to death.

The study authors concluded that “the improvements in median progression-free survival achieved by ripretinib in this study and the INVICTUS study represent valuable clinical benefit for patients with advanced GIST, who currently have no effective standard therapy available after third-line therapy.”

Source:

Li J, Cai S, Zhou Y, et al. Efficacy and safety of ripretinib in Chinese patients with advanced gastrointestinal stromal tumors as a fourth- or later-line therapy: A multicenter, single-arm, open-label phase II study. Clin Cancer Res. Published online: June 29, 2022. doi:10.1158/1078-0432.CCR-22-0196.