Clinical Trial Details
— Status: Completed
Administrative data
NCT number |
NCT02171065 |
Other study ID # |
PROSPECT II & PROSPECT ABSORB |
Secondary ID |
|
Status |
Completed |
Phase |
N/A
|
First received |
|
Last updated |
|
Start date |
June 2014 |
Est. completion date |
May 2020 |
Study information
Verified date |
July 2021 |
Source |
Uppsala University |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
The present study has two components, an overall prospective observational study using
multimodality imaging (PROSPECT II) that will examine the natural history of patients with
unstable atherosclerotic coronary artery disease with the specific goal to establish the
utility of low-risk intracoronary imaging modalities, IVUS and NIRS, to identify plaques
prone to future rupture and clinical events. The randomized PROSPECT ABSORB substudy will
examine whether treatment of vulnerable plaques with the Absorb Bioresorbable vascular
scaffold (BVS) plus GDMT safely increases the minimum lumen area (MLA) at 24 months compared
with GDMT alone.
The cutoff for inclusion in PROSPECT ABSORB will be a site-determined PB ≥65% (rather than
the 70% cutoff identified in the original PROSPECT analysis (Stone et al., New England
Journal of Medicine, 2011(5)) to account for an observed tendency for sites to underestimate
plaque burden during acute treatment of ACS patients. Nonetheless, in PROSPECT, a core
laboratory determined PB ≥65% was also associated with a high (7.0%) rate of major adverse
cardiac event (MACE) during 3-year follow-up, a rate which may be reduced with a
bioresorbable scaffold.
Description:
Methodology:
PROSPECT II: Multicenter, prospective, natural history study of troponin positive patients
with acute coronary syndromes (ACS) examined with angiography and intended for PCI for the
initial culprit lesion(s). Prior to PCI all target lesions (those lesions for which PCI is
planned) will be examined (if possible) by IVUS/NIRS. After successful PCI of all
flow-limiting lesions determined angiographically and/or by FFR/iFR intended to be treated
(termed "culprit lesions," whether responsible for the original ACS or otherwise
flow-limiting and requiring PCI for complete revascularization), intravascular ultrasound
(IVUS), and intracoronary near infrared spectroscopy (NIRS) will be performed over a 6-10 cm
length in all three coronary arteries with a combined IVUS/NIRS catheter. Clinical and
register follow-up will identify all new coronary events, the origin of which will be
determined by follow-up angiography when clinically indicated. These lesions will be
identified and compared to the baseline examination at a central angiographic and IVUS/NIRS
core laboratory, and adjudicated to have arisen from either originally treated culprit
lesions or untreated "non-culprit lesions." This will allow determination of the baseline
patient-related and lesion-related variables in culprit and non-culprit lesions that increase
the risk for future unanticipated cardiovascular events.
PROSPECT ABSORB (Randomized Trial): Patients with angiographically non-obstructive lesions
that are not intended to undergo PCI based on the current standard of care, and that are
site-assessed by IVUS to have plaque burden of ≥65% (which has previously been shown in the
first PROSPECT study to identify lesions at high risk of causing future coronary events
despite their non-obstructive angiographic appearance) will be randomized (1:1) to treatment
with ABSORB BVS + guideline directed medical therapy (GDMT) versus GDMT alone. All such
randomized patients will undergo repeat angiography and IVUS/NIRS after 25 months of
follow-up.
Patient enrollment and procedure overview:
PROSPECT II: Patients with a troponin positive ACS within the prior 4 weeks (STEMI >12 hours
or NSTEMI) in whom coronary angiography is planned will be screened and asked to participate
in the study. After informed consent has been obtained and prior to PCI, all target lesions
(those lesions for which PCI is planned) will be examined (if possible) by IVUS/NIRS. If the
patient is successfully treated with PCI of all intended culprit lesions without major
procedural complication(s), all three coronary arteries will be examined with IVUS/NIRS. The
IVUS results will be visible (unblinded) to the operator, but the NIRS data will be blinded.
The patient will be considered formally enrolled in PROSPECT II only after PCI of all
intended target culprit lesions has been successfully completed with no major
complication(s), and after the study imaging catheter is passed out of the guide catheter
into a coronary artery (n = approximately 900 patients). If a staged procedure is required to
achieve revascularization of all intended lesions, the patient will not be enrolled until
after the staged procedure has been performed without major procedural complication(s). Once
enrolled, IVUS and NIRS will be performed over a 6-10 cm length in all three coronary
arteries with a combined IVUS/NIRS catheter to assess both the treated culprit lesion(s) and
long segments of the untreated coronary tree. Patient enrollment and 3-vessel IVUS and NIRS
imaging may be performed either in the same procedure during which the culprit PCI lesion(s)
are treated, or during a subsequent angiographic procedure as long as this occurs within 4
weeks of the initial ACS presentation, and after successful and uncomplicated treatment of
all target lesions. If the imaging catheter passed into a coronary artery for imaging a
non-culprit segment of the coronary tree and no non-culprit segment imaging data is obtained
(e.g. the catheter fails and a second catheter is not used), the patient will be disenrolled
(discontinued) from the study, and only be followed up for safety purposes for 30 days.
PROSPECT ABSORB: Patients in whom one or more lesions are identified with (a) an
angiographically visually estimated diameter stenosis of <70%; (b) a visually estimated
reference vessel diameter (RVD) of 2.5 - 4.0 mm; (c) a visually estimated lesion length ≤50
mm; d) a site determined IVUS PB ≥65%; and (e) is located at least 10 mm from a previous
stent and at least 10 mm of intervening segment between the previous stent and the
non-culprit lesion does not have PB >50% will be enrolled in the PROSPECT ABSORB trial and
randomized 1:1 to treatment with ABSORB BVS + GDMT versus GDMT alone (n = approximately 300
patients, 150 patients in each group). For patients with multiple qualifying lesions, a
single lesion will be selected for randomization prior to assignment to BVS + GDMT versus
GDMT alone.
Study follow-up:
PROSPECT II (Natural History Study)
Clinical follow-up:
Patients will be followed in the Scandinavian quality registers (eg, SWEDEHEART). Patients
will undergo follow-up through register data collection and by calls by study coordinators at
1 month (30 days), 6 months (180 days), 12 months, and 24 months, assessing MACE and safety
parameters. MACE will be followed in all patients throughout the whole study period until
last patient has been followed for 24 months. Patients will then undergo follow-up through
register data collection at yearly intervals starting at 3 years and through 15 years.
Additional phone follow-up to patients may also be performed.
PROSPECT ABSORB (Randomized Trial)
Clinical follow-up:
Patients will be followed in the Scandinavian quality registers (eg, SWEDEHEART). Patients
will undergo follow-up through register data collection and by calls by study coordinators at
1 month (30 days), 6 months (180 days), 12 months, and 24 months. MACE will be followed in
all patients throughout the whole study period until last patient has been followed for 24
months. Patients will then undergo follow-up through register data collection at yearly
intervals starting at 3 years and through 15 years, with additional phone follow-up subject
to Executive Committee approval.
Angiographic follow-up:
All patients randomized in PROSPECT-ABSORB will undergo routine angiographic and 3-vessel
IVUS/NIRS follow-up at 25 months; ie, 1 month after the 24 month telephone follow-up. The 25
month angiogram may be performed within a window of between 24.5 months and 28 months after
enrollment.
Note: 25-month angiographic follow-up will not be required in PROSPECT-ABSORB randomized
patients who either a) have had scaffold thrombosis or in-scaffold restenosis (DS>50% as
determined by the angiographic core laboratory) at any time point prior to 25 months, OR b)
have had a repeat angiogram ≥12 months after enrollment and in whom IVUS/NIRS of the
randomized target lesion was performed.