In this post-hoc analysis, we evaluated anlotinib treatment-induced hypertension as a potential predictive factor of efficacy in esophageal squamous cell carcinoma (ESCC) patients.

A total of 109 patients enrolled in the anlotinib group in a phase 2 trial were included. The tumor response was assessed by computed tomography at week 3, week 6, and then every 6 weeks until progressive disease was observed. The primary endpoint of the study was progression free survival (PFS). The secondary endpoints included overall survival (OS) and objective response rate (ORR).

In all patients, the median PFS was 3.02 months [95% confidence interval (CI): 2.63–3.65 months] and the OS was 6.11 months (95% CI: 4.40–7.79 months). The ORR was 7.34% (95% CI: 3.22%–13.95%). A total of 59 (54%) patients were diagnosed with treatment-induced hypertension (Group A), and the remaining patients (n = 50, 46%) were in Group B. Baseline prognostic factors were similar between the 2 groups. Patients in Group A had a longer PFS and OS and higher ORR. When stratifying patients using a previously known history of hypertension, treatment-induced hypertension was a predictor only for patients without previous hypertension, who had longer PFS [hazard ratio (HR): 0.40, 95% CI: 0.24–0.68] and OS (HR: 0.37, 95% CI: 0.21–0.67).

We showed, for the first time, a correlation between treatment-induced hypertension and better prognoses in recurrent or metastatic ESCC patients treated with anlotinib, without a previously known history of hypertension. Treatment-induced hypertension may be a simple and low cost predictor for anlotinib antitumor efficacy in these patients, which may also reflect the intended target inhibition.