Mechanisms Underlying Hypotensive Response to ARB/NEP Inhibition - Aim 2
Status:
Recruiting
Trial end date:
2023-10-01
Target enrollment:
Participant gender:
Summary
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.
Objectives
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.
Phase:
Phase 4
Details
Lead Sponsor:
Vanderbilt University Medical Center
Treatments:
Antihypertensive Agents Bradykinin Icatibant LCZ 696 Sacubitril and valsartan sodium hydrate drug combination