(Fast-Track proposals will be accepted.)
Number of anticipated awards: 1
Budget (total costs): Phase I: $200,000
for 12 months; Phase II: $1,500,000 for 2 years
It is strongly suggested that proposals
adhere to the above budget amounts and project periods. Proposals
with budgets exceeding the above amounts and project periods may not
be funded.
Summary
Mechanical stents to relieve obstructive
cardiovascular lesions could have great utility in pediatric
cardiology, but are unsuitable for small children. Commercially
available stents limit vessel growth and require future surgical
removal. Absorbable stents might revolutionize the treatment of
congenital heart disease in children. Small children require small
delivery systems for devices that are larger than adult coronary
arteries. Specific target diseases include aortic coarctation and
pulmonic stenosis, which currently require open surgical repair or
multiple X-ray-guided catheter procedures in early childhood.
Project Goals
These are transcatheter stents to be
delivered using conventional interventional cardiovascular
techniques including guiding catheters or sheaths, translesional
guidewires, and balloon-expandable or self-expanding delivery
systems. Conventional and novel approaches are welcomed.
Specific requirements of the stents
include small delivery systems (5-6 French or smaller); sufficient
radial force to resist elastic recoil for the two applications;
sustained radial strength suited to the application for at least 6
months; controlled degradation within 6-12 months; inflammatory
response that does not cause significant stenosis, restenosis, or
aneurysm; resistance to downstream embolization or toxicity; and
nominal calibers suitable for the most common lesions (pulmonary
artery stenosis and aortic coarctation, see below) .
Proposed stent nominal geometry should be
diameter (6-10mm), length (range 10-25mm), delivery system (5-6
French or smaller). The radial hoop strength of the deployed device
should approach that of commercial balloon-expandable stent such as
the Cordis Palmaz Genesis. Percutaneous vascular access routes for
the pulmonary artery application include femoral and jugular venous.
Percutaneous vascular access routes for aortic coarctation
application include transvenous-transeptal antegrade and retrograde
transfemoral artery. The implant or the delivery system should be
conspicuous under the intended image-guidance modality. Offerings
should specifically provide the high radial force required to
overcome immediate recoil of the intended applications, and should
allow Òdirect stentÓ treatment technique for native and iatrogenic
lesions.
Phase I Activities and Expected
Deliverables
Phase I should focus on mechanical and
biological performance of the proposed biodegradable stents in the
intended use for pulmonary artery stenosis and aortic coarctation,
taking into account mechanical strength required for the
application; geometry of the access vessels and geometry and
morphology of target vessels including tapering and branching;
strategies to avoid inflammatory restenosis or constriction; and
delivery, implantation, and visualization strategies.
At the conclusion of phase I, a candidate
device design should be selected for clinical development based on
in vivo performance of a mature prototype resembling a
final design. The sponsoring NHLBI laboratory is willing to perform
a limited number in vivo proof-of-principal experiments in
swine (by mutual agreement) to confirm mechanical performance.
Phase II Activities and Expected
Deliverables
At the conclusion of phase II, the offeror
should obtain an investigational device exemption (IDE), and a
supply of devices provided, for a first-in-human research protocol,
involving at least 10 subjects, to be performed by the sponsoring
NHLBI laboratory. The sponsoring NHLBI laboratory is willing to
perform a limited number of in vivo proof-of-principal
experiments in swine (by mutual agreement). NHLBI offers to perform
the clinical trial at no expense to the offeror, to participate in
the development of the clinical protocol, and to provide clinical
research services. The vendor is expected to perform or obtain
safety-related in vivo experiments and data to support the
IDE.
The specific Phase II deliverables are as
described under Phase I.
- The phase II award would consist of the contractor obtaining
an IDE based on the design finalized in phase I.