To All:
I just got this E-mail from Gwen at Alliance:
Dear Alliance NetFriend:
The following was prepared in an effort to keep you apprised of recent
events concerning Oxygent, Alliance's temporary oxygen carrier ("blood
substitute"). I hope you will find it informative.
Sincerely,
Gwen Rosenberg
Director, Corporate Communications
OXYGENT (PERFLUBRON EMULSION) UPDATE...
CLINICAL STATUS
A meeting was held with the FDA last week to discuss the results of our
Phase II studies with Oxygent, and our proposals for a Phase III program.
We believe that the meeting was very productive, and we are now preparing
protocols for Phase III studies that we intend to initiate shortly.
As reported previously, the completed U.S. and European Phase II surgical
studies demonstrated that Oxygent was significantly more effective than
blood in reversing transfusion triggers, which are physiologic indications
of when a patient requires a transfusion. Oxygent also delayed the need for
a subsequent blood transfusion significantly longer than blood, and the
product was well-tolerated by patients in both studies.
Data from the U.S. trial was presented at the March meeting of the
International Anaesthesia Research Society. The study investigators
concluded that, "The effectiveness of PFC [Oxygent] is likely attributable
to its ability to rapidly increase PvO2 [partial pressure of oxygen],
reflecting rapidly increasing tissue oxygen tension+" Results from the
European trial will be presented at the European Society of Anaesthesia
meeting in Barcelona, Spain, at the end of April.
In addition to the general surgery Phase II studies, Phase IIa studies with
cardiopulmonary bypass (CPB) patients have been completed. Initial data
from the CPB studies will be reported in April at the American Society of
Cardiovascular Anesthesiologists meeting in a presentation entitled,
"Perflubron emulsion administration during cardiopulmonary bypass -
preliminary results of increased cerebral blood flow."
PUBLICATIONS AND PRESENTATIONS
Alliance was pleased to have Oxygent featured on the cover of the February
1998 issue of "Transfusion, the Journal of the American Association of Blood
Banks." The issue also contained the following article about a preclinical
study with the product:
* "Hemodilution and intravenous perflubron emulsion as an alternative
to blood transfusion: effects on tissue oxygenation during profound
hemodilution..."
Excerpt: Direct comparison of the PFC [Oxygent] and control groups
revealed better tissue oxygenation in the PFC group, as reflected by
significantly higher mixed venous, coronary venous, and local tissue pO2
[partial pressure of oxygen] of liver and skeletal muscle.
A graphic showing Oxygent+s emulsion particles was featured on the back
cover of a recently published book, "Blood Substitutes: Principles, Methods,
Products and Clinical Trials" (1998, Karger Landes Systems). Two chapters
of the book provide information about Oxygent:
* Chapter 6 - "Fluorocarbon-Based Oxygen Delivery: Basic Principles &
Product Development"
Excerpt: Fluorocarbon-based emulsions such as Oxygent are ideally
suited as temporary "blood substitutes"...Administration of Oxygent to
maintain tissue oxygenation during surgery with acute normovolemic
hemodilution is expected to result in increased safety by preventing tissue
hypoxia and reduction of exposure to allogeneic blood transfusion.
* Chapter 7 - "Perfluorochemical [PFC] Emulsions: Future Alternatives
to Transfusion"
Excerpt: Because PFC emulsions do not produce any adverse hemodynamic
effects (e.g., no increase in heart rate or vascular resistance) they do not
alter total oxygen consumption under normal baseline conditions. Thus,
addition of a PFC-based oxygen carrier should produce increases in
plasma-dissolved oxygen content, tissue oxygenation, pO2 of the blood
draining from the tissues, and the pO2 of mixed venous blood. All of these
have been demonstrated in various preclinical models.
Oxygent was also the subject of a chapter in the book, "Red Blood Cell
Substitutes - Basic Principles and Clinical Applications" (1998, Marcel
Dekker, Inc.):
* "Efficacy of Perflubron-Based Emulsion as a Temporary Oxygen Carrier"
Excerpt: The [preclinical] data summarized in this chapter...support
the conclusion that intravenous perflubron-based emulsion improves tissue
oxygenation in critical tissues such as heart and brain, that the increased
O2 is available to support the metabolic processes that occur at the
mitochondrial level in these tissues, and that this improved metabolic
status does, indeed, translate into an improvement in organ function. These
studies also demonstrate the efficacy of intravenous perflubron-based
emulsion to support systemic oxygenation during hemodilution and
intraoperative surgical bleeding, as well as in the setting of
cardiopulmonary bypass surgery.
Two presentations regarding Oxygent were made at the IBC 5th Annual
Conference on Blood Substitutes meeting in Cambridge, Mass:
* "Prevention of Tissue Hypoxia Using Perflubron Emulsion as a
Temporary Oxygen Carrier"
Excerpt: Extensive studies in more than 200 healthy volunteers and
surgical patients have clearly established the safety of perflubron
emulsion...These studies demonstrated the absence of any direct effects on
platelet function, template bleeding times, and coagulation parameters. In
addition, there was no evidence of any complement activation or immunogenic
reactions; no suppression of humoral or cell-mediated immune function; no
abnormal changes in liver, pulmonary, or renal function; no clinically
meaningful effect on blood chemistry; and no hemodynamic effects or
vasoconstriction.
* "Clinical Applications of Perfluorochemical Emulsions"
Excerpt: Perfluorochemical emulsions can enhance oxygen delivery in
patients sustaining acute blood loss, and the safety and efficacy of
autologous blood conservation techniques such as acute normovolemic
hemodilution may be augmented. The submicron particle size of perflubron
emulsion is advantageous when tissue perfusion is compromised as a result of
low flow states or vascular occlusion (cerebrovascular and peripheral
vascular disease and cardiac surgery).
Thank you for your interest in Oxygent and Alliance Pharmaceutical Corp. If
you have any questions or if you would like full copies of the publications
cited in this letter, please contact me via e-mail, telephone at (619)
558-4375, or fax at (619) 678-4133.
Sincerely,
Gwen Rosenberg
Director, Corporate Communications |
