Mechanisms Underlying Hypotensive Response to ARB/NEP Inhibition - Aim 2

  • End date
    May 14, 2024
  • participants needed
  • sponsor
    Vanderbilt University Medical Center
Updated on 14 June 2022
ejection fraction
heart failure
enzyme inhibitors
beta blockers
b-type natriuretic peptide
ace inhibitor
natriuretic peptide
beta-adrenergic blocking agents
angiotensin converting enzyme
angiotensin ii receptor antagonists
n-terminal pro-bnp


LCZ696, a molecular complex of the angiotensin receptor blocker (ARB) valsartan with an inhibitor of neprilysin (NEP, neutral endopeptidase-24.11) sacubitril improved mortality compared to enalapril in patients with heart failure (HF), reduced ejection fraction (EF), and increased brain natriuretic peptide (BNP) or N-terminal pro-BNP (NT-proBNP) in the PARADIGM-HF trial.1 The PIONEER-HF study demonstrated the efficacy of LCZ696 in preventing rehospitalization in patients with acutely decompensated HF.2

LCZ696 has been underutilized in heart failure, in part due to concerns about hypotension. NEP degrades several vasodilator peptides including bradykinin, substance P and brain-type natriuretic peptide. Decreased degradation of endogenous bradykinin could contribute to hypotension at initiation of LCZ696 through vasodilation or through increased natriuresis and diuresis. Inhibition of the bradykinin B2 receptor using icatibant would be expected to prevent this effect.


The main objectives of this mechanistic randomized, double-blind, crossover-design study are:

  • The primary objective is to test the hypothesis that endogenous bradykinin contributes to effects of ARB/NEP inhibition on blood pressure, natriuresis, and diuresis at initiation.
  • The secondary objective is to test the hypothesis endogenous bradykinin contributes to effects of ARB/NEP inhibition on blood pressure, natriuresis, and diuresis after up-titration.

Eighty (80) subjects with stable heart failure who meet all inclusion/exclusion criteria will be enrolled. Subjects who qualify will collect their urine for 24 hours before each study day for measurement of volume, sodium and potassium. At the start of the study, they will stop their regular angiotensin-converting enzyme (ACE) inhibitor or ARB. After a 48-hour washout, they will undergo a study day in which they are given a single dose of 50 mg LCZ696. They will also receive either the bradykinin B2 receptor antagonist icatibant or placebo vehicle in random order (double-blind). After a 96-hour washout, they will repeat the study day and receive a single dose of 50 mg LCZ696 and the opposite study drug (icatibant or placebo). After completion of the two acute study days, subjects will take LCZ696 50 mg bid for two weeks, followed by LCZ696 100 mg bid for three weeks, and then LCZ696 200 mg bid, following the conservative up-titration protocol from the TITRATION study.3 Criteria for continuing up-titration appear in the full study protocol. On the 7th and 10th day of the 200 mg bid or highest tolerated dose, subjects will again undergo two more study days three days apart in which they are randomized to receive either icatibant or vehicle.

Condition Heart Failure
Treatment Placebo, Iohexol, Para-Aminohippurate, LCZ 696, Icatibant
Clinical Study IdentifierNCT04113109
SponsorVanderbilt University Medical Center
Last Modified on14 June 2022


Yes No Not Sure

Inclusion Criteria

Black and white men and women
Stable patients with a reduced ejection fraction (EF)
EF ≤40%, and
history of symptoms of New York Heart Association (NYHA) class I, II, or III heart failure (HF)
stable clinical symptoms including no hospitalizations for the last six months
who are not already taking LCZ696
treatment with a stable dose of an angiotensin-converting enzyme inhibitor (ACEi) or
for patients with NYHA Class II or III HF, treatment with a stable dose of an mineralocorticoid receptor (MR) antagonist for at least four weeks, unless not possible due to renal function or serum potassium
angiotensin receptor blocker (ARB) and with a beta blocker (unless
For female subjects, the following conditions must be met
contraindicated or not tolerated) for at least four weeks
postmenopausal status for at least one year, or
status post-surgical sterilization
or if of childbearing potential, utilization of barrier methods of birth control or an oral contraceptive and willingness to undergo urine β- human chorionic gonadotropin (HCG) testing on every study day

Exclusion Criteria

History of hypersensitivity or allergy to any of the study drugs, drugs of similar chemical classes, ACEi, ARBs, or neutral endopeptidase inhibitor (NEPi), as well as known or suspected contraindications to the study drugs
History of angioedema
History of decompensated HF within the last three months (exacerbation of chronic HF manifested by signs and symptoms that required intravenous therapy or hospitalization)
History of heart transplant or on a transplant list or with left ventricular assistance device
Symptomatic hypotension and/or a systolic blood pressure (SBP)<100 mmHg at screening or <95 mmHg during the study
Serum potassium >5.2 mmol/L at screening or >5.4 mmol/L during the study
Impaired renal function (eGFR of <30mL/min/1.73 m2) as determined by the four-variable Modification of Diet in Renal Disease (MDRD) equation, where serum creatinine (Scr) is expressed in mg/dL and age in years
eGFR (mL/min/1.73 m2)=175 • Scr-1.154 • age-0.203 • (1.212 if Black) • (0.742
if female)
Acute coronary syndrome, cardiac, carotid, or other major cardiovascular surgery, percutaneous coronary intervention, or carotid angioplasty within six months prior to screening
Coronary or carotid artery disease likely to require surgical or percutaneous intervention within six months of screening
History of serious neurologic disease such as cerebral hemorrhage, stroke, seizure, or transient ischemic attack
History of ventricular arrhythmia with syncopal episodes
Symptomatic bradycardia or second- or third-degree atrioventricular block without a pacemaker
Presence of hemodynamically significant mitral and/or aortic valve disease, except mitral regurgitation secondary to left ventricle (LV) dilatation
Presence of other hemodynamically significant obstructive lesions of the LV outflow tract, including aortic and subaortic stenosis
Type 1 diabetes
Poorly controlled type 2 diabetes mellitus (T2DM), defined as a HgbA1c >9%
In T2DM, dipeptidyl peptidase-4 inhibitor use for one month prior to enrollment will be excluded due to possible interaction with LCZ696
Hematocrit <35%
Breast feeding and pregnancy
History or presence of immunological or hematological disorders
History of malignancy not felt to be cured, except non-melanoma skin cancer
Diagnosis of asthma requiring use of inhaled beta agonist more than once a week
History of hypersensitivity reaction to contrast
Clinically significant gastrointestinal impairment that could interfere with drug absorption
History of pancreatitis or known pancreatic lesions
Impaired hepatic function [aspartate amino transaminase (AST) and/or alanine amino transaminase (ALT) >3.0 x upper limit of normal range]
Any underlying or acute disease requiring regular medication which could possibly pose a threat to the subject or make implementation of the protocol or interpretation of the study results difficult, such as arthritis treated with non-steroidal anti-inflammatory drugs
Treatment with chronic systemic glucocorticoid therapy within the last year
Treatment with lithium salts
History of alcohol or drug abuse
Treatment with any investigational drug in the one month preceding the study
Mental conditions rendering the subject unable to understand the nature, scope, and possible consequences of the study
Inability to comply with the protocol, e.g., uncooperative attitude, inability to return for follow-up visits, and unlikelihood of completing the study
Clear my responses

How to participate?

Step 1 Connect with a study center
What happens next?
  • You can expect the study team to contact you via email or phone in the next few days.
  • Sign up as volunteer  to help accelerate the development of new treatments and to get notified about similar trials.

You are contacting

Investigator Avatar

Primary Contact


Additional screening procedures may be conducted by the study team before you can be confirmed eligible to participate.

Learn more

If you are confirmed eligible after full screening, you will be required to understand and sign the informed consent if you decide to enroll in the study. Once enrolled you may be asked to make scheduled visits over a period of time.

Learn more

Complete your scheduled study participation activities and then you are done. You may receive summary of study results if provided by the sponsor.

Learn more

Similar trials to consider


Browse trials for

Not finding what you're looking for?

Every year hundreds of thousands of volunteers step forward to participate in research. Sign up as a volunteer and receive email notifications when clinical trials are posted in the medical category of interest to you.

Sign up as volunteer

user name

Added by • 



Reply by • Private

Lorem ipsum dolor sit amet consectetur, adipisicing elit. Ipsa vel nobis alias. Quae eveniet velit voluptate quo doloribus maxime et dicta in sequi, corporis quod. Ea, dolor eius? Dolore, vel!

  The passcode will expire in None.

No annotations made yet

Add a private note
  • abc Select a piece of text from the left.
  • Add notes visible only to you.
  • Send it to people through a passcode protected link.
Add a private note