Evaluation of GeranylGeranylAcetone in heart failure with preserved ejection fraction

Heart failure with a preserved ejection fraction (HFpEF), characterized by
stiffening of the left ventricle and impaired filling, comprises the majority
of heart failure cases and accounts for ±2% of the total EU healthcare budget
(±30 billion Euro*s per year). In contrast to heart failure with a reduced
ejection fraction (HFrEF), treatment options are limited. Sacubitril/valsartan
has shown some benefit in subgroups of HFpEF patients,1 and empagliflozin has
been shown in 2021 to reduce hospitalization rates in HFpEF.2 As no other
treatment options exist, there is a major unmet clinical and societal need for
safe, effective, and affordable treatments for HFpEF.
Early in the pathogenesis of HFpEF, compromised endothelial synthesis
of nitric oxide (NO) and decreased levels of small heat shock proteins (HSPs),
such as HSP27 and αB-Crystallin, cause stiffening of the cardiomyocytes.3-5 αB-
Crystallin and HSP27 determine the conformation of the cytoskeletal protein
titin and control muscle stiffness, and deficiency of αB-Crystallin greatly
increases muscle stiffness.6 It has been proposed that αB-Crystallin and HSP27
determine the conformation of the flexible N2b part of titin, which is
phosphorylated by cGMP-activated protein kinase (PKG). PKG activity in
cardiomyocytes is controlled by the microvascular endothelium through NO and
soluble guanylate cyclase (sGC).7 Microvascular dysfunction in the myocardium,
particularly decreased synthesis of NO by capillary endothelium, is a second
determinant of cardiomyocyte stiffness.
The prenylating agent geranylgeranylacetone (GGA), chemical name
teprenone and currently sold outside of the EU by Eisai Co. Ltd. as part of the
anti-ulcer agent Selbelle (before december 2020: Selbex), has been shown to
enhance cardiomyocyte HSP expression as well as microvascular NO activity, both
in animal models and in human studies. In RECONNECT, we demonstrated that 4
weeks of oral GGA administration decreases cardiomyocyte stiffness in hearts of
ZSF1 rats by increasing the expression of HSP27 and αB-Crystallin (Waddingham,
Handoko, Eringa, Paulus et al., manuscript in revision). The enhancing effect
of oral GGA treatment on myofilament HSP27 abundance was replicated in patients
undergoing bypass surgery.8 Furthermore, GGA was shown to enhance endothelial
NO activity through HSP90 expression in healthy humans.9 In the context of
kidney disease, GGA was shown to induce renal HSP70, ameliorate tubular damage
and prevent deterioration of kidney function in acute and chronic models of
kidney damage.10-12 These beneficial effects of GGA have been attributed to
improvement of endothelial function, leading to favorable changes in kidney
blood flow. While GGA has beneficial effects in man on key elements of the
pathogenesis of HFpEF, i.e. increasing HSP activity and improving endothelial
function, while being well tolerated in patients, and exerts beneficial effects
on myocardial stiffening in a model of HFpEF, proof of efficacy of GGA on signs
and symptoms of HFpEF in man is lacking.9

Since 1984, GGA has been used as an over-the-counter anti-ulcer drug in
Asian countries, with minor side effects at doses up to 1200 mg/day.13 In fact,
this marketed effect of GGA is mediated by NO, and this GGA-induced increase in
NO activity can now be tested for its therapeutic potential in HFpEF.14 In
2021, the sole manufacturer of pure GGA for human use is the Amsterdam UMC. In
addition, the Stichting VUMC is holder of the patent for GGA as a treatment for
diastolic dysfunction. We aim to use this opportunity, our combined expertise
and the proven effects of GGA in man, for a phase 2 trial on the efficacy of
GGA in HFpEF.
In the CVON-RECONNECT project on HFpEF funded by the Netherlands heart
foundation, we provided proof of concept that cardiac capillary endothelium
controls cardiomyocyte function through transfer of NO and that this specific
endothelial function is impaired in human chronic kidney disease.4,15 Previous
studies have shown that in HFpEF microvascular NO synthesis is reduced and that
microvascular dysfunction predicts severity.5,16 Taken together, HSP expression
and microvascular NO synthesis control cardiomyocyte stiffness in health and in
human HFpEF and chronic kidney disease.
In the proposed phase 2 trial, we expect to obtain proof of concept for
a beneficial effect of GGA on HFpEF. In HFpEF patients we will evaluate effects
of GGA on signs and symptoms of HFpEF including echographic parameters of
diastolic function, exercise tolerance, microvascular endothelial function and
kidney function.

Primary objectives
To study whether Geranyl-Geranyl Acetone (GGA) reduces left ventricular (LV)
diastolic dysfunction in patients with HFpEF compared to placebo (and to
assess/confirm its effectiveness and safety in patients with HFpEF)

Secondary objectives
• To assess whether GGA improves endothelial function in patients with HFpEF
compared to placebo.
• To assess whether GGA improves renal (hemodynamic) function in patients with
HFpEF compared to placebo
• To assess whether GGA improves self-reported quality of life and exercise
tolerance in patients with HFpEF compared to placebo

Exploratory objectives
• To assess whether GGA changes biomarker profiles in patients with HFpEF
compared to placebo

The design of the study will be a crossover multi-centre, double-blind,
randomized control trial. The reversibility of the effect of GGA on HSP
expression in human subjects enables a crossover study and the washout period
for our groups is comparable to similar studies in patients with HFpEF.9,17,18
A schematic overview of the study is provided below (Figure 1).
After eligibility is checked and informed consent is obtained, baseline
measurements are performed (Table 1). We will take a patient history, general
measurements like weight, body mass index (BMI) and vital signs and perform a
physical examination on baseline. Furthermore, we will ask patients to fill in
questionnaires regarding their quality of life (QoL).
EndoPAT-measurements, kidney function measurements and laboratory
values will be obtained after both treatment arms. The measurement after the
placebo arms will provide us with baseline information regarding EndoPAT and
kidney function.

The participants in the study will be treated with the prenylating agent GGA
300mg/day.

In the GLADIATOR-HFpEF trial we study GGA (*Teprenone*, *Selbex*) which is an
over-the-counter anti-ulcer drug authorized in Japan. GGA has not been proven
to have functionality in patients with HFpEF, but GGA has been shown to enhance
the expression of HSP*s in the human heart and endothelial cells, which
determine cardiomyocyte stiffness and the synthesis of nitric oxide (NO).28
Literature and data from a phase I trial from the RECONNECT-consortium
shows that 4 weeks of GGA treatment reverses cardiomyocyte stiffening and halts
the diastolic dysfunction in ZSF-1 rats, which is a model for patients with
HFpEF, (Waddingham, Eringa et al., manuscript under review), rats and patients
undergoing coronary artery bypass graft (CABG).8,29
Side-effects of GGA have been thoroughly documented and have a low
incidence (<0.5%). The dosage in which we aim to use GGA (300mg/day) is
four-fold lower compared to the dosage that has been safely given to patients
with gastritis and gastric ulcers.23
As vascular endothelium is present in all organs and tissues and HSPs
are a ubiquitous mechanism for cellular protection from stressors, the
mechanism induced by GGA is not selective to one tissue or organ. Despite this,
only minor adverse side effects of GGA have been reported (see above). In
contrast and consistent with pleiotropic effects of GGA-induced HSP expression,
beneficial and protective effects of GGA have been reported in the brain, the
lungs, and kidneys.
The most common side effects for GGA are elevated plasma concentrations
of liver enzymes (0.2%). Other side-effects have a lower incidence (<0.1%) and
can be found in the supplementary *Selbex Bijsluiter*. To cover possible
side-effects, we will perform safety lab tests for elevated liver enzymes after
each treatment period of 13 weeks. Furthermore, we will take a patient history
while patients are on-treatment at every follow-up visit to check for other
side-effects.
The study population has been selected according to the
power-calculation described in 4.4. The reversibility of the effect of GGA on
HSP expression in human subjects enables a crossover study, which reduces the
amount of people subjected to treatment. Patients will be their own controls.
We will only include patients with diagnosed HFpEF who are in a stable
condition and exclude women who are pregnant or have a wish for pregnancy.
Patients will stay on their own heart failure medication as there are no
reports of interacting medication with GGA. In case of hypersensitivity to GGA
or any SAE that can be directly attributed to the use of GGA we will stop
medication immediately and unblind the subject and inform the treating
physician and PI/sponsor.
Since this study has a relatively low treatment time (2x13 weeks), a
low number of included patients (40) and a low risk of side-effects and SAE*s
as described above we will not institute a DSMB. We will have a monitoring and
quality assurance plan to ensure the safety of the participants and the quality
of the data.
We admit that the study protocol may be intense due to multiple tests
that are performed, considering that these patients are physically compromised.
However, we would like to stress out that each test is easy to perform and very
low risk. All tests will be planned at one single day, to minimize the burden
for the study participant. Participants will be compensated for costs of
parking and a lunch is provided for them and their caregiver if relevant. Also,
the total number of physical visits is 4-5 and the complete protocol will be
finished within half a year. On the other hand, treatment options in HFpEF are
very limited, and GGA treatment may be beneficial to the study participant at
relative low risk, which cannot be prescribed otherwise. All considering, we
believe that disadvantages and benefits of the study are in balance.