Renal Denervation Using Stereotactic Radiotherapy System for the Treatment of Refractory Hypertension

Study Overview
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Brief Summary
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This study is conducted to investigate the short-term safety and preliminary efficacy of stereotactic radiotherapy for renal denervation to treat refractory hypertension.

Detailed Description
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This will be a single centre, single arm, prospective cohort study. Patients with refractory hypertension will receive single fraction stereotactic radiotherapy for renal denervation. The study has been designed in a careful and stepwise dose escalation fashion in order to minimize the potential risks associated with this innovative technique. The dose escalation is guided by 3+3 algorithm to ensure more patients will be spared dose limiting toxicities and more patients will be entered on the dose level that will be chosen as optimal dose of maximal effect. Low dosing levels with established safety profile will first be applied before administering higher dosing levels based on preclinical studies. Safety is the primary endpoint of this study. Safety will be assessed by incidence and evaluation of any serious adverse events using CTCAE v5.0 criteria associated with the procedure through 90 days. Efficacy will be evaluated by assessing mean reduction in average 24-hour ambulatory blood pressure at 90 days post-treatment.

Official Title
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Renal Denervation Using Stereotactic Radiotherapy System for the Treatment of Refractory Hypertension

Conditions
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Hypertension

Intervention / Treatment
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* Radiation: stereotactic body radiotherapy (SBRT)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 55 and ≤ 75 years. Systolic blood pressure of 160 mmHg or greater despite being treated with at least three hypertensive drugs for more than 3 months. Exclusion Criteria: GFR < 45 ml/min/1.73 m2. Known causes of secondary hypertension. Hospitalized for hypertensive crisis within 1 year. History of acute coronary syndrome or cerebrovascular accident within the last 6 months. Pregnancy or have a pregnancy plan. Contrast media or iodine allergy. History of abdominal radiotherapy or adhesive intestinal obstruction. Severe valvular heart disease. Stenosis >50% or renal artery aneurysm in either renal artery. Others.

Ages Eligible for Study
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Minimum Age: 55 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: stereotactic body radiotherapy (SBRT)<br>Noninvasive SBRT will be delivered in a single fraction to bilateral renal arteries determined by CT-guidance. | Radiation: stereotactic body radiotherapy (SBRT)<br>* Image-guided stereotactic body radiation therapy<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Safety Endpoint | Safety will be assessed by incidence and evaluation of any serious adverse events using CTCAE v5.0 criteria that are related to the procedure. | 90 days | 
| Ambulatory Blood Pressure Reduction | Mean reduction in average 24-hour ambulatory blood pressure at 90 days post-treatment | 90 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Office Blood Pressure Reduction | Mean reduction in office blood pressure at 90 days post-treatment | 90 days | 
| Number of Drug Adjustments | Number of drug adjustments for hypertension through 90 days after treatment | 90 days |