Clinical Trial Details
— Status: Recruiting
Administrative data
NCT number |
NCT03207945 |
Other study ID # |
17-22800 |
Secondary ID |
|
Status |
Recruiting |
Phase |
Phase 3
|
First received |
|
Last updated |
|
Start date |
April 30, 2018 |
Est. completion date |
July 2025 |
Study information
Verified date |
June 2023 |
Source |
University of California, San Francisco |
Contact |
Shreya Swaminathan |
Phone |
628-206-5801 |
Email |
shreya.swaminathan[@]ucsf.edu |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
Atherosclerosis in the setting of HIV infection is distinct and includes increased vascular
inflammation, worsened endothelial function, and a predominance of non-calcified plaque.
These outcomes can be assessed using specialized noninvasive imaging which strongly predict
future CV events in the general population.
PCSK9 has emerged as an important pharmacologic target for cholesterol lowering in the
general population and recent studies among individuals without HIV have shown that PCSK9
inhibitor therapy is safely tolerated and significantly reduces major CV events in the
general population.
The investigators will perform a clinical trial of PCSK9 inhibition in the setting of HIV
infection. This will be a randomized, placebo-controlled study to evaluate the effects of
PCSK9 inhibition on vascular inflammation, endothelial function, and non-calcified plaque
using a PCSK9 inhibitor called alirocumab. This study will recruit 140 treated individuals
with HIV who are aged 40 and older, with known CVD or risk factors for CVD and who have
evidence of vascular inflammation at baseline.
The primary and secondary objective of this study is to determine whether PCSK9 inhibition
can improve arterial inflammation as assessed by FDG-PET/CT and endothelial function as
assessed by flow mediated vasodilation. The investigators will correlate changes in arterial
inflammation and endothelial function with lipids and markers of inflammation and immune
activation.
The tertiary objective is to perform a pilot evaluation of the impact of PCSK9 inhibition on
non-calcified plaque as measured by coronary CT angiography. Non-calcified plaque
measurements will be correlated with changes in lipid parameters and markers of inflammation
and immune activation.
Description:
Cardiovascular disease (CVD) due to atherosclerosis continues to be the leading single cause
of death in industrialized countries. High serum lipid levels, and especially high
low-density lipoprotein cholesterol (LDL-C) levels, have been demonstrated to strongly and
directly correlate with CVD risks by numerous epidemiological studies. Moreover, large
prospective clinical outcome trials have demonstrated that lowering LDL-C decreases
cardiovascular morbidity and mortality. A meta-analysis of 26 randomized clinical trials
comprising 170,000 participants showed that more intensive statin therapy compared to less
intensive regimens will reduce coronary deaths or myocardial infarction by an additional 13%.
HIV-infected individuals represent a unique and increasing subset of atherosclerosis. With
the advent of antiretroviral therapy, HIV-infected individuals now have much improved
survival and are faced with health issues related to aging, including cardiovascular disease.
Individuals with HIV have higher rates of coronary events compared to controls even in the
setting of treated and suppressed disease and a growing body of literature suggests that they
are at increased risk for myocardial infarction, atherosclerosis, and sudden cardiac death.
Many facets of atherosclerosis differ in HIV-infected individuals compared to uninfected
individuals with atherosclerosis. HIV-infected patients with acute coronary syndromes are
younger and more likely to be males and smokers, with low high density
lipoprotein-cholesterol (HDL-C), compared to other acute coronary syndrome patients. With
respect to pathophysiology, viral replication, antiretroviral drugs all contribute to
atherosclerosis.
HIV-associated inflammation induces pro-atherogenic lipid abnormalities and anti-retroviral
therapy leads to the development of metabolic abnormalities such as dyslipidemia,
lipodystrophy and insulin resistance. In a large cross-sectional study, 27% of subjects
receiving combination therapy including a protease inhibitor had a total cholesterol level
exceeding 240 mg/dl, compared to 8% of untreated HIV subjects, and 40% had triglyceride
levels above 200 mg/dl, compared to 15% in untreated subjects. The prevalence and severity of
dyslipidemia varies among different antiretroviral drugs; however, hypertriglyceridemia and
low HDL-cholesterol were associated with HIV infection even before the advent of
antiretroviral therapy. Total, HDL-C, and LDL-C decrease at the time of HIV infection, and
with antiretroviral treatment total and LDL-C levels increase to pre-infection levels while
HDL-C remains low.
Abnormalities in body composition have been reported in 40-50% of HIV-infected patients, with
higher rates in those receiving combination antiretroviral therapies. Subcutaneous
lipoatrophy commonly affects the face, limbs, and buttocks, and is accompanied by central fat
accumulation. Hyperinsulinemia is often also present. In a representative study, diabetes was
present in 7% of HIV-infected adults with fat accumulation or lipoatrophy, as compared to
0.5% of control subjects matched for age and BMI. The corresponding rates of glucose
intolerance were 35% and 5% respectively. Compared to healthy control subjects, HIV-infected
men treated with combination antiretroviral therapy were 4 times as likely to develop
diabetes over a 3-year observation period.
The increased cardiovascular risk and dyslipidemia in HIV-infected individuals is difficult
to treat for several reasons. Statins reduce LDL-C levels less in HIV-infected individuals
compared to uninfected controls. Fibrates reduce triglyceride levels less in HIV-infected
individuals compared to uninfected controls as well. Drug-drug interactions between statins
and protease inhibitors increase the risk of adverse events. Due to these interactions,
simvastatin and lovastatin are contraindicated among individuals receiving protease
inhibitors and the dose of atorvastatin should not exceed 40 mg. Even interactions with
rosuvastatin, which is not metabolized by the cytochrome P450 system, have been described.
As a consequence, physicians may avoid treating HIV-infected individuals who would benefit
from statins, or use lower doses or less potent statins, reducing the potential for
cardiovascular event reduction. High triglyceride levels in HIV-infected subjects are common,
and the combination of a fibrate plus antiretroviral therapy increases the risk of drug-drug
adverse events, even before consideration of a statin.
Statin treatment reduces lipid levels modestly in HIV subjects. Among 72 HIV-infected
subjects in the SATURN-HIV trial randomized to rosuvastatin 10 mg/day, LDL-C was reduced by
25.3% by week 24. In another study, of 83 HIV-infected subjects, rosuvastatin 10 mg and
pravastatin 40 mg/day reduced LDL-C by 37% and 19% respectively at 45 days. Among 151
HIV-infected subjects randomized to rosuvastatin 10 mg, atorvastatin 10 mg, or pravastatin 40
mg/day, LDL-C reductions were greater with rosuvastatin at this dose, but all 3 statins
significantly and similarly reduced serum levels of hs-CRP and TNF-a.
Approximately 1/3 of individuals with HIV-infection are co-infected with hepatitis C.
Elevated hepatic enzymes due to hepatitis C represent a relative contraindication to statin
therapy, and some evidence suggests that a statin might increase hepatitis C activity.
Finally, HIV-infected patients often need many medications and have a large daily pill
burden. Compliance suffers, but has been shown to improve when single tablet regimens reduce
daily pill load. Long-acting injectable antiretroviral drugs are under development as a
strategy to reduce pill burden and improve compliance. PCSK9 inhibitor injections would
dovetail well with this approach. For these reasons, PCSK9 inhibitor therapy offers
advantages over statin therapy in this unique population.
That statins might favorably influence the evolution of atherosclerosis in HIV-infected
subjects is suggested by a recent trial where 40 HIV subjects with mild coronary
atherosclerosis by CT angiography and aortic inflammation by FDG-PET imaging were randomized
to atorvastatin 20-40 mg/day or placebo and were followed for 12 months. Atorvastatin
significantly reduced non-calcified coronary plaque volume relative to placebo, as well as
the number of high-risk plaques.
In the HIV-uninfected population, statin therapy produced significant and rapid
dose-dependent reductions in FDG update that were reflective of changes in atherosclerotic
plaque inflammation. In addition, lipoprotein apheresis resulted in significant reduction of
arterial inflammation. Recently, addition of evolocumab was found to result in a greater
decrease in percent atheroma volume using intravascular ultrasound. All of these studies
which were performed in the non-HIV population provide a strong scientific rationale for
studying the role of PCSK9 inhibition in HIV. Namely, given the strong association between
HIV, noncalcified plaque, and arterial inflammation, PCSK9 therapy may play a unique role in
reducing HIV-associated atherosclerosis, Alirocumab (Sar236553/REG 727) is a fully humanized
monoclonal antibody against the proprotein convertase subtilisin kexin type 9 (PCSK9) enzyme
responsible for the degradation of the low-density lipoprotein receptor (LDLR), and is
developed by Regeneron Pharmaceuticals/Sanofi. In a randomized trial of 2341 patients with
heterozygous familiar hypercholesterolemia or with established coronary heart disease or a
CHD risk equivalent with LDL levels≥70mg/dL and were receiving treatment with statins at the
maximum tolerated dose with or without other lipid-lowering therapy. Patients were randomly
assigned to a 2:1 ratio to receive alirocumab 150mg or placebo every 2 weeks for 78 weeks. At
week 24 the difference between the alirocumab and placebo groups from baseline to calculated
LDL was -62 percentage points. The alirocumab group had higher rates of injection site
reactions, myalgia, neurocognitive events and ophthalmologic events. The rate of major
adverse cardiovascular events was lower in the alirocumab group as compared to placebo in a
post hoc analysis (p=0.02).
Preliminary data on 6 HIV-infected individuals inadvertently enrolled in a PCSK9 inhibitor
study using evolocumab demonstrated that LDL was lowered 60%, along with significant
reductions in triglycerides and Lp(a) and was well tolerated (unpublished data)
Based on these findings a dose of 75 mg every 2 weeks for 6 weeks followed by an upward
titration to 150 mg every 2 weeks for those with LDL-C >50 mg/dl for the remainder of the
study for this trial will be used. Based on population PK/PD modeling, a dose of 150 mg every
2 weeks in patients on a background of statins is estimated to be equivalent to approximately
80% of the maximal response for LDL-C lowering (-67%). Assuming an average LDL C at baseline
of 100 mg/dL for HIV-infected individuals, the mean absolute LDL-C reduction is predicted to
be approximately -60 mg/dL.