HIF-2α Inhibitor Casdatifan Demonstrates 15-Month Progression-Free Survival in Advanced Kidney Cancer
核心洞察
Casdatifan, a next-generation HIF-2α (搜索) inhibitor, achieved a median progression-free survival of 15.1 months in patients with metastatic clear cell renal cell carcinoma (搜索) at the 100 mg daily dose.
The drug demonstrated a 45% objective response rate with all responses being partial responses in the 100 mg cohort, with a median time to response of 2.6 months.
Safety analysis showed manageable adverse events across all doses, with anemia (搜索) and hypoxia (搜索) being the most common grade 3 or higher treatment-emergent adverse events.
The HIF-2α (搜索) inhibitor casdatifan has demonstrated promising efficacy in later-line treatment of metastatic clear cell renal cell carcinoma (搜索) (ccRCC (搜索)), with progression-free survival exceeding one year in the phase 1/1b ARC-20 study. After a median follow-up of 17.9 months among 31 patients treated with a 100 mg daily dose, the median progression-free survival reached 15.1 months (95% CI, 5.7-not evaluable).
Efficacy Results Show Sustained Disease Control
The 100 mg daily cohort achieved impressive milestone survival rates, with 68% of patients remaining progression-free at 6 months (95% CI, 48%-81%) and 61% maintaining progression-free survival at 12 months (95% CI, 42%-76%). In a broader pooled analysis of 121 patients across multiple dose levels, including 50 mg twice daily, 50 mg daily, and 150 mg daily doses, the median progression-free survival was 12.2 months (95% CI, 9.4-16.5) after a median follow-up of 20.8 months.
The confirmed objective response rate in the 100 mg cohort reached 45% (95% CI, 27%-64%), with all responses classified as partial responses. The pooled analysis demonstrated a 35% objective response rate (95% CI, 26%-44%), with all but one response being partial responses. Disease control rates were substantial in both groups, reaching 84% (95% CI, 66%-95%) in the 100 mg cohort and 81% (95% CI, 73%-88%) in the pooled analysis.
Rapid Response and Biomarker Correlation
Patients experienced relatively rapid responses to treatment, with a median time to response of 2.6 months in the 100 mg cohort and 2.8 months in the pooled analysis. According to Toni K. Choueiri, MD, director of the Lank Center for Genitourinary Oncology at Dana-Farber (搜索) and lead investigator of the ARC-20 trial, "An analysis of data for casdatifan, a next-generation HIF-2α (搜索) inhibitor, showed the majority of patients reached near-maximal serum erythropoietin reduction, and that deep and prolonged suppression was associated with better response and clinical benefit."
Patient Population and Study Design
The phase 1/1b dose-escalation and expansion trial enrolled patients who had primarily experienced progression following at least two prior lines of therapy, including an anti-PD-1 (搜索) agent and a VEGFR (搜索) tyrosine kinase inhibitor. Eligible patients required at least one measurable lesion per RECIST guidelines and an ECOG performance status score of 1 or lower. The study excluded patients who had received live vaccines within four weeks of study start or had a history of trauma or major surgery within 28 days prior to the first study dose.
Safety Profile Remains Manageable
The safety analysis revealed no unexpected signals, with casdatifan's safety profile proving generally manageable across all doses. Serious treatment-emergent adverse events occurred in 31% of both the 100 mg group and the pooled analysis. The most common grade 3 or higher treatment-emergent adverse events included anemia (搜索), affecting 25% of the 100 mg group and 41% of the pooled analysis, and hypoxia (搜索), occurring in 9% and 11% respectively.
Treatment discontinuation due to adverse events occurred in 9% of patients in both groups, with hypoxia (搜索) being the primary cause. In the 100 mg cohort, one patient (3%) discontinued due to hypoxia, while three patients (2%) in the pooled analysis discontinued for the same reason.
Clinical Implications for Kidney Cancer Treatment
Dr. Choueiri emphasized the broader significance of these findings, stating, "HIF-2α (搜索) inhibition has emerged as a novel treatment that is changing the treatment paradigm for patients with ccRCC (搜索), and the results from ARC-20 are very encouraging." The study's primary endpoints focused on dose-limiting toxicities and adverse event incidence, while secondary endpoints included objective response rate and pharmacokinetic parameters.
The complete dataset from this study will be presented in a poster session at the 2026 American Society of Clinical Oncology Genitourinary Cancer Symposium, providing the medical community with comprehensive data on this promising therapeutic approach for patients with advanced kidney cancer.