Risk factor analysis for regorafenib-induced severe hypertension in metastatic colorectal cancer treatment

Regorafenib, a multikinase inhibitor, is effective in treating metastatic colorectal cancer (mCRC). Hypertension is a frequently occurring adverse effect caused by regorafenib regardless of previous treatment with vascular endothelial growth factor (VEGF) inhibitors in almost all patients. We identified the risk factors associated with regorafenib-induced severe hypertension. Patients with mCRC (n = 100) who received regorafenib were evaluated retrospectively. The primary endpoint was the evaluation of the risk factors for grade ≥ 3 hypertension. The association between pre-existing hypertension at baseline and grade ≥ 3 hypertension symptoms was also assessed. Patients with pre-existing hypertension at baseline accounted for 55% of the total patients. The starting doses of regorafenib were 160 mg (49.0% of patients), 120 mg (29.0%), and 80 mg (22.0%). The incidence of grade ≥ 3 hypertension was 30.0%. The median time to grade ≥ 3 symptom development was 7 days (range: 1-56 days). Additional antihypertensive treatment was administered to 83.6% of patients who developed hypertension. Logistic regression analyses revealed that baseline pre-existing hypertension complications and previous anti-VEGF treatment for ≥ 700 days were independent risk factors for grade ≥ 3 hypertension development. Further analyses revealed that pre-existing hypertension before anti-VEGF treatment (primary hypertension) was significantly related to the symptom development (adjusted odds ratio, 8.74; 95% confidence interval, 2.86-26.72; P = 0.0001). Our study suggests that pre-existing primary hypertension and previous anti-VEGF treatment for ≥ 700 days are independent risk factors for regorafenib-induced severe hypertension. Deeper understanding of the symptom nature and management can significantly contribute to safer interventions, necessitating further studies.