Clinical Trial Details
— Status: Completed
Administrative data
NCT number |
NCT03166306 |
Other study ID # |
2017P000249 |
Secondary ID |
|
Status |
Completed |
Phase |
Phase 1/Phase 2
|
First received |
|
Last updated |
|
Start date |
May 1, 2018 |
Est. completion date |
March 31, 2020 |
Study information
Verified date |
May 2021 |
Source |
Brigham and Women's Hospital |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
Pulmonary arterial hypertension (PAH) is a disorder of elevated pulmonary vascular resistance
characterized by progressive remodeling and obliteration of vessels of the distal pulmonary
circulation. Outcomes in PAH could be improved with earlier diagnosis, and with the early
deployment of therapies before irreversible changes have occurred. This study tests the
sensitivity of positron emission tomography (PET)-CT scanning with [89Zr]-bevacizumab, a
radioisotope-conjugated anti-VEGF antibody for detecting pulmonary vascular remodeling in PAH
disease. This test could enable non-invasive diagnosis early in the course of the disease,
and potentially improve outcomes in PAH,
Description:
PAH is a disease of progressive remodeling and obliteration of the distal pulmonary
vasculature. The overexpression of VEGF-A in the pulmonary vasculature of patients with PAH
and animal models of disease is thought to reflect a process of disordered angiogenesis that
is tightly coupled to disease progression. It is hypothesized that positron emission
tomography (PET)-CT scan utilizing [89Zr]-bevacizumab, a radioisotope-conjugated humanized
monoclonal antibody against VEGF-A, would provide a sensitive and specific molecular imaging
modality to detect pulmonary vascular remodeling activity.
To test this hypothesis the investigators propose a Phase I/II pilot study to enroll 10
patients with known severe idiopathic or familial PAH, 10 individuals with
exercise-associated PAH (EPAH), thought to be a mild and early stage of PAH, and 10 healthy
volunteers with no evidence of cardiopulmonary disease. This pilot study will compare
standardized uptake values (SUV) for the retention of [89Zr]-bevacizumab in the distal
pulmonary vasculature in these three populations. The kinetics of equilibration and wash-out
of this probe will be assessed with sequential scans at 4 and 7 days following the injection
of radionuclide. In patients with PAH or EPAH, repeat scans will be performed 1 year after
the initial scan to assess whether changes in clinical status correlate with
[89Zr]-bevacizumab retention.
The ability of these protocols to discriminate between the lungs of healthy individuals
versus patients with PAH or EPAH will be evaluated using the measure of peripheral lung
tissue probe SUV, corresponding to distal pulmonary vessel uptake, normalized to the proximal
aortic SUV, corresponding to the blood pool. These data will be used to define normative
values for healthy controls versus PAH patients, and to generate cutoffs in signaling ratios
with optimal sensitivity and specificity for disease detection. These normative ranges will
be applied to the EPAH cohort to determine if this test retains sensitivity and specificity
for a potentially milder, earlier form of PAH.
This study is divided into 4 Aims:
AIM 1: Test the hypothesis that expression of VEGF-A discerned by [89Zr]-bevacizumab imaging
is increased in the distal pulmonary vascular bed in PAH patients compared to healthy
individuals.
AIM 2: Test the hypothesis that expression of VEGF-A discerned by [89Zr]-bevacizumab imaging
is increased in the distal pulmonary vascular bed in patients with exercise-associated PAH
compared to healthy individuals.
AIM 3: Ascertain whether or not distal pulmonary vascular uptake of [89Zr]-bevacizumab
correlates with clinical markers of PAH severity, including 6 minute walk distance, New York
Heart Association functional class, right atrial pressure, mean pulmonary artery pressure,
pulmonary vascular resistance, cardiac index, NT-proBNP, tricuspid annular plane systolic
excursion (TAPSE) by echocardiography.
AIM 4: Ascertain whether or not changes in distal pulmonary vascular uptake of
[89Zr]-bevacizumab over 1 year in patients with PAH or EPAH correlates with changes in
clinical status based on clinical markers of PAH severity.