Renal Denervation in ADPKD- RDN-ADPKD Study

• Introduction:Increased blood pressure (BP) is a common finding in patients with autosomal dominant polycystic kidney disease (ADPKD) which is one of the leading causes of end stage renal disease. Previously, it was shown that hypertensive patients with ADPKD have increased sympathetic nerve activity regardless of renal function. This was one of the pathogenetic mechanisms that leads to the progression of renal failure, even independent of BP. Recent clinical studies have indicated that invasive, catheter-based renal denervation (RDN) decreases sympathetic nerve activity. Up to date, only two single case reports have suggested a safe and effective procedure of RDN in an ADPKD patient with uncontrolled hypertension.
• Study purpose: The purpose of the RDN-ADPKD pilot study is to demonstrate efficacy and document safety of RDN with the Paradise System in hypertensive patients with ADPKD.
• Study design: RDN-ADPKD is a prospective, randomized (1:1, central randomization), single-center, hypothesis-generating, feasibility study.

Patients are randomized into (immediate) I-RDN-group and (delayed) D-RDN-group, respectively. After 3 months, patients in the D-RDN-group will undergo RDN-procedure and will be followed for additional 36 months. Hence, study design allows several comparisons both of whole study group (at same time-point of follow-up) as well as between I-RDN-group and D-RDN-group.

• Patient population: 44 hypertensive patients with ADPKD are randomized with 22 patients allocated to the I-RDN-group and 22 patients to the D-RDN-group (receiving RDN after 3 months), respectively.
• Primary endpoint: The primary endpoint of this pilot study is the change in systolic 24-h ambulatory BP at 3 months post-procedure in the whole study group (irrespective whether treated immediate [I-RDN-group] or delayed [D-RDN-group]) compared to baseline.
• Visit and Follow-Up Schedule: The primary objective will be assessed at 13 weeks (3 months) post-procedure in both groups. Scheduled in-clinic follow-up (FU) visits will occur at least at 13 (3 months) and 26 (6 months) 52 (12 months), 78 weeks (18 months),104 weeks (24 months), 130 weeks (30 months) and 156 weeks (36 months) post procedure; however, scheduled Follow-Up visits at 3, 7,20 weeks, 78 weeks and 130 weeks post-procedure are possible as in-clinic FU visit as well as ambulant visit at the allocation centre(s) of the referring physician.
• Randomization: The subjects will be randomized to I-RDN group or D-RDN group at Visit 2.
• Medication Adherence: Adherence to drug therapy will be captured by interviewing patients, checking the patient's BP diary and by urinary toxicological analysis at baseline, 26 weeks, 52 weeks, 104 weeks and 156 weeks post-procedure visit.
• Safety Signals: A major combined safety endpoint is the incidence of any major adverse events (MAE) through the 36 months Follow-up.
• Escape Criteria: Enrolled subjects will be excluded:

• if home BP increases to ≥160 systolic or ≥100 mmHg diastolic pre-randomization, confirmed by office (attended) BP ≥170/105 mmHg will be excluded
• if office (attended) BP exceeds ≥170/105 mmHg pre-randomization, confirmed by 7-day average of home BP measurements ≥ 160/100 mmHg (excluding white coat effect) or confirmed by office (attended) BP ≥170/105 mmHg at another study visit.
• Ethics: The study will be conducted in accordance with the declaration of Helsinki, REGULATION (EU) 2017/745, EN ISO 14155:2020, FDA 21 CFR parts 50, 54, 56, 812 and other applicable local and national regulations.

Inclusion criteria

• Patients with ADPKD
• Systolic office (attended) BP ≥130 mmHg or diastolic office (attended) BP ≥80 mmHg confirmed by 24-h ambulatory BP systolic ≥125 mmHg or diastolic ≥75 mmHg despite treatment with 1-4 drug classes (RAS blockade is mandatory, unless intolerance to RAS blockers has been documented) The rationale of these inclusion criteria reflect the November 2021 updated knowledge of RDN according to international consensus reports, in particular in face of conducting clinic studies and randomized controlled trials and does not necessarily reflect the current application of RDN in clinical practice). Moreover, the most recent updated KDIGO guidelines recommend a target office BP < 120 mmHg in patients with chronic kidney disease.1.
• Patient is adhering to a stable drug regimen without changes for a minimum of 4 weeks
• Individual is ≥ 18 years of age, both genders are included

Exclusion criteria

• eGFR < 40ml/min/1.73m² (according to the currently used estimation formulas: MDRD (Modification of Diet in Renal Disease), CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration))
• Anatomically significant renal artery abnormality in either renal artery which in the eyes of the interventionalist would interfere with safe catheter placement
• Prior renal denervation procedure
• Office (attended) BP ≥180 mmHg systolic and/or ≥110 mmHg diastolic
• 24-h ambulatory BP ≥160 mmHg systolic
• Other cause of hypertension that can be treated by intervention/surgery (e.g. hemodynamically relevant renal artery stenosis, functional adrenal adenoma)
• Type 1 diabetes mellitus
• Proteinuria (>3g/g Kreatinin)
• Contraindication to MRI
• Individual has experienced a myocardial infarction, unstable angina pectoris, or a cerebrovascular accident within 3 months of the screening visit
• Subject is pregnant, nursing, or intends to become pregnant
• Enrollment in another interventional research protocol
• Any condition that, at the discretion of the investigator, would preclude participation in the study (e.g. non-adherence)