Chiauranib plus weekly paclitaxel significantly extends progression-free survival (PFS) in patients with platinum-resistant or -refractory ovarian cancer, including those previously treated with anti-angiogenic agents, according to the findings of the phase III CHIPRO trial presented at ASCO 2026.
Approximately 15–20 percent of ovarian cancer cases are primary platinum-resistant, meaning that progression occurs during treatment or within 6 months of completing initial platinum-based chemotherapy. [Oncotarget 2017;8:85759-85771; JCO Glob Oncol 2026;12:e2500650]
“Tumour resistance in ovarian cancer is a complex process involving multiple pathways,” said presenter Dr Xiaohua Wu from Fudan University Shanghai Cancer Center, Shanghai, China. “Chiauranib selectively inhibits Aurora B kinase and targets three pathways: suppression of tumour cell proliferation via G2/M arrest; CSF1R/PDGFRs/DDR1 inhibition, which reprogrammes the immune-suppressive tumour microenvironment; and VEGFR/PDGFR inhibition, which blocks angiogenesis and tumour progression.”
The phase III randomized, double-blind, placebo-controlled CHIPRO study (n=459), which was conducted exclusively in China, included 12.7 percent of patients with platinum-refractory disease in the chiauranib plus paclitaxel (CP) group (n=228) and 7.8 percent in the placebo plus paclitaxel (PP) group (n=231). Approximately 46 percent of patients in both groups had a platinum-free interval after initial platinum-based therapy of <6 months. “CHIPRO is the first randomized study with a substantial primary platinum-refractory population, making it highly relevant to real-world practice,” stressed Wu. [ASCO 2026, abstract LBA5504]
Approximately 28 percent of patients had ≥3 lines of prior therapy and around 70 percent had prior VEGF/VEGFR inhibitor therapy. Prior PARP inhibitor therapy was recorded in 51 and 54 percent of patients in the CP and PP groups, respectively.
“The primary endpoint of PFS was significantly improved in the CP vs PP group,” reported Wu. “The median PFS was 4.57 vs 2.69 months. The hazard ratio [HR] was 0.43 [95 percent confidence interval (CI), 0.34–0.54; p<0.001], indicating a 57 percent reduction in the risk of progression or death.”
The PFS benefit of CP was consistently observed across all prespecified subgroups, including those aged ≥65 years (HR, 0.23; 95 percent CI, 0.11–0.51; p<0.001), those with ≥3 lines of prior therapy (HR, 0.52; 95 percent CI, 0.34–0.82; p=0.003), and those with prior PARP inhibitor therapy (HR, 0.38; 95 percent CI, 0.28–0.52; p<0.001). Significant PFS benefit was also observed regardless of prior anti-angiogenic therapy, and the HRs were almost identical between patients with and without prior exposure (with prior VEGF/VEGFR inhibitor: HR, 0.44; 95 percent CI, 0.33–0.57; p<0.001; without prior VEGF/VEGFR inhibitor: HR, 0.44; 95 percent CI, 0.32–0.67; p<0.001).
There was no statistically significant difference in the second primary endpoint of overall survival (OS) between the two groups. The median OS was approximately 12 months in the intent-to-treat population. “However, we did see some interesting trends in some specific subgroups. For example, in patients without subsequent anticancer therapy, median OS was 7.4 months in the CP group vs only 4.7 months in the PP group [HR, 0.599; 95 percent CI, 0.39–0.91; p=0.016],” highlighted Wu.
Grade ≥3 treatment-emergent adverse events (TEAEs) were considerably more frequent in the CP vs PP group (90.4 vs 54.3 percent). While TEAEs leading to interruption (68.4 vs 32.6 percent) or dose reduction (37.3 vs 12.6 percent) of chiauranib or placebo occurred more frequently in the CP group, the proportion of patients affected by TEAEs that led to discontinuation was broadly similar between the two groups (6.1 vs 4.8 percent).