A pivotal trial of safety and efficacy of ADRCs delivered via the intracoronary route in the treatment of patients with ST-elevation acute myocardial infarction â¤* The ADVANCE Trial

The use of adult stem cells from several sources has been shown to improve
cardiac function in acute and chronic cardiac disease. A number of pilot trials
using intramyocardial injection of bone marrow mononuclear cells have shown
promising results in patients with chronic myocardial disease as an adjunct to
bypass surgery in patients with ischemic heart failure, and in patients after
an acute myocardial infarction. In addition, many randomized trials have shown
a significant benefit of treatment with bone marrow mononuclear cells in acute
myocardial infarction (AMI). Many investigations showed small (<5%) improvement
of left ventricular ejection fraction (LVEF) secondary to improvements in left
ventricular dimensions. However more recent studies have shown that decrease in
left ventricular infarct size plays a more significant role in morbidity and
mortality of AMI patients. While the mechanisms of infarct size reduction
remain incompletely elucidated, this remarkable process is believed to involve
a number of mechanisms including: anti-apoptosis, paracrine effects,
neo-angiogenesis and perhaps differentiation. Many sources for adult stem cells
have been discovered including bone marrow, skeletal muscle, blood and adipose
tissue. Autologous adipose-derived regenerative cells (ADRCs) are obtained from
subcutaneous adipose tissue by processing lipoaspirate. Preparation of
therapeutic doses of ADRCs involves no cell culture and can be achieved in less
than two hours from the time of donor tissue acquisition. This allows for
treatment during the same procedure as harvest of the adipose tissue, obviating
the need for a second visit.

However, while the majority of studies have shown improvement in cardiac
function at least in the short term. Long term follow-up suggest that, for some
patients, the benefit may be transient. That is, one study has shown that for
patients with hypertension or with less severe heart attacks bone marrow cell
therapy delays rather than prevents loss of diastolic function such that by
five years after treatment a substantial proportion (though not all) of the
difference between treated and control patients is lost1. On the other hand,
the same study noted that the treatment effect is sustained at five years in
patients with larger transmural infarcts. Other studies have suggested similar
increased benefit in patients with more severe injury2;3. This is consistent
with the design of the present study (ADVANCE) which limits inclusion to only
those patients with more severe, transmural infarcts.

When ADRCs are prepared using Cytori*s proprietary extraction, washing and
concentration methods, the resultant cell suspension contains at least two
different cell types that are known to be important for healing and tissue
regeneration but the suspension is void of any *fat-cells* (adipocytes). These
cells include adipose derived stem cells and endothelial precursor cells among
others. ADRCs are multipotent cells capable of differentiating into multiple
lineages in vitro, such as adipocytes, osteoblasts, chondrocytes, myocytes,
hepatocytes, and neurons in vitro, given the appropriate specific conditions
and stimulating factors. While similar to bone marrow derived adult stem cells
in differentiation potential, the usual abundance of adipose tissue in human
patients and the higher frequency of adult stem cells per unit mass allows fast
isolation of an efficacious number of cells without having to culture expand
them.
In Cytori*s feasibility (APOLLO) clinical study, detailed in the Investigators
Brochure, ADRCs at a dose of 20 X 106 were infused into the coronary arteries
of AMI patients, resulting in no safety related adverse events related to the
infusion, clinically relevant

The objective of this study is to determine the Safety and Efficacy of ADRCs
delivered via the intracoronary route in the treatment of patients with
ST-elevation acute myocardial infarction (STEMI).

Investigation of stem and regenerative cell therapy has been evaluated in
several therapeutic areas because of their known therapeutic effect in tissue
regeneration, angiogenesis and reduction of cell death (see Cytori*s
Investigators Brochure for detailed information). Adult stem cells can be
obtained from various sources, such as bone marrow, blood, and adipose tissue.
Adipose tissue has been demonstrated to provide an abundant, easily accessible
source of autologous stem cells with multilineage differentiation and
self-renewal properties.
Pre-clinical data and the previous (APOLLO) clinical study using of ADRCs
prepared with Cytori*s proprietary process have demonstrated safety and
functional improvement in STEMI. In addition, results of the APOLLO study
demonstrated a clinically relevant although not statistically significant
improvement in left ventricular infarct size and myocardial perfusion compared
to placebo. Data from peer-reviewed publications have shown that reduction in
left ventricular infarct size has a more important impact on morbidity and
mortality in AMI patients than measures of ejection fraction.
Preparation of ADRCs with Cytori*s proprietary process involves no cell culture
and can be achieved within two hours from the time of donor tissue acquisition
by liposuction. The use of freshly isolated cells obviates the need for a
second hospitalization or anesthetic for treatment. Therapy can be provided
without the delay necessitated by days or weeks of cell culture, commonly
observed with the use of mesenchymal stem cells obtained from bone marrow.

This is a prospective, two-stage seamless group sequential phase II/III,
randomized, 3 arm, placebo-controlled, double blind, study that will enroll up
to 365 subjects at no more than thirty-five (35) international clinical
sites. Additional blinding measures will be taken in the assessment of study
outcomes. The doses of the test material (ADRCs) for each arm are described in
Test Materials, Section 5.1. The study will include up to three arms, with as
many as 144 treated patient, and 77 placebo patients. Within each group,
subjects will be randomly assigned in a 2:2:1 ratio to receive the test
material at up to thirty-five active clinical sites.
When a subject has been randomized to receive either dose of the test material,
adipose-derived regenerative cells (ADRCs) will be isolated from the
lipoaspirate and then infused into the ischemic area of the heart via an
intracoronary catheter. When randomized to receive placebo, a standardized
Lactated Ringer*s solution will be injected using the same procedure as with
the test material.

In this study, as it was in the previous (APOLLO) study, best practices for the
treatment of acute myocardial infarction are followed, eliminating unnecessary
delay in the primary treatment of the patient*s AMI; however, this design
necessitates a second catheterization during the same hospitalization for
infusion of the active substance or placebo.
There is one planned interim analysis upon completion of the six-month follow
up visit of at least 105 enrolled patients (42,42,41 in dose one, dose two and
placebo groups respectively).

After screening patients will undergo a liposuction to harvest the ADRCs. The
Cells will be injected in the target coronary vessels after a slective coronary
angiogram has been made. This is repeated after cell injection.

The Safety of liposuction and intracoronary injection of ADRCs in patients with
AMI have been demonstrated by Cytori in the APOLLO and PRECISE studies. In
APOLLO, there where no adverse events related to intracoronary injection of
ADRCs with no negative changes in TIMI flow or CFR; and liposuction adverse
events occurred in only 2 patients, both had pharmacologically induced
abnormalities of their clotting cascade from glycoprotein inhibitors and
anticoagulants. After the protocol was modified to exclude glycoprotein
inhibitors and control the use of heparin, no significant bleeding events
occurred. Liposuction routinely involves the subcutaneous administration of
Lactated Ringer*s solution that contains a local anesthetic and epinephrine
(*tumescent solution*). In the APOLLO and PRECISE studies, significant systemic
hemodynamic effects of these two agents were not observed. Although not
observed in APOLLO, intracoronary infusion of cells could result in an acute
reduction in blood flow, manifested by decrease in coronary flow (CFR & TIMI)
due to micro capillary blockage of the vascular bed. Therefore to monitor and
guard against this occurrence, coronary flow (CFR) measurements and TIMI flow
grading will be assessed during and after the transplantation procedure. Other
similar cells, including stems cells derived from bone marrow, have been
successfully delivered using this route with similar risks and complications as
other coronary interventions2,14,22. Study patients will be informed of risks
(listed in Sections 1.3.3 * 1.3.9) and benefits associated with this procedure
via the informed consent process. Safety of the transplantation procedure will
be continuously monitored by the Co-PI*s and site Investigators, and will be
part of each DMC review. Any possible events associated with this procedure
will be reviewed by the CEC.