MIAMI, FL -- 09/05/07 --
DOR BioPharma, Inc. (OTCBB: DORB) ("DOR" or the
"Company") announced today results from animal testing of RiVax(TM), its
vaccine against ricin toxin, have been published online in the journal
Vaccine, Smallshaw et al., "RiVax(TM), A Recombinant Ricin Subunit Vaccine,
Protects Mice Against Ricin Given by Gavage or Aerosol" (web link to
article:
http://dx.doi.org/doi:10.1016/j.vaccine.2007.08.018). The
publication describes the findings that RiVax(TM) can induce protection
against mortality and tissue damage from both aerosol and oral toxin
exposure; the most likely routes to be used in a ricin toxin biological
attack. The publication was authored by investigators at the University of
Texas Southwestern Medical Center at Dallas (UT Southwestern), one of the
Company's academic partners in the development of RiVax(TM).
RiVax(TM) is already known to induce antibodies that appear primarily in
the blood of animals and humans. Such antibodies in the blood are
correlated to protection against exposure when the toxin reaches the
circulation. One of the major effects of ricin toxin exposure through the
lungs is rapid and massive lung injury that leads to death. It was not
known how well RiVax(TM) would protect when ricin toxin was inhaled or
ingested. This recent study demonstrated that RiVax(TM) not only protects
mice against the lethal effects of the aerosolized toxin, but it can also
prevent damage to lung tissue. RiVax(TM) protected animals against lung
injury as measured by lung function tests and histological lesions induced
by the toxin in a dose-dependent manner, where the amount of antibodies
circulating in the blood correlated directly to protection against lung
injury. It was also confirmed that RiVax(TM) protected mice against lethal
effects when they were fed the ricin toxin. These results indicate that it
is possible to induce antibodies primarily in circulation that are
correlated with protection when the toxin contacts lung and
gastrointestinal tissue.
"It is now clear that RiVax(TM) induces excellent protection against oral
and aerosol ricin toxin exposure, and protects mucosal tissue against the
direct effects of the toxin," said Ellen Vitetta, PhD, Director of the
Cancer Immunobiology Center at UT Southwestern and the study's
corresponding author. "The current results also show that pure ricin toxin
is 2000 fold more toxic by the oral route than previously described, which
is very surprising, since the literature has described much larger doses to
cause mortality when ricin is fed to animals."
"We have always believed the potential for a biological attack with
aerosolized ricin toxin to be significant given its ease of production;
therefore, it was critical to demonstrate that RiVax(TM) protected against
aerosol exposure," said Robert N. Brey, PhD, DOR's Chief Scientific
Officer. "The next step will be to evaluate RiVax(TM) as protection
against aerosol exposure in a higher animal species. The correlation of
antibodies with protection against aerosol exposure will be a critical
component necessary to support the use of RiVax(TM) in humans as a licensed
vaccine or under emergency use authorization. We think that these results
provide strong evidence that an injected form of RiVax(TM) will prove
sufficient to induce antibodies to protect mucosal tissues in the lung as
well as the gastrointestinal tract."
The Company has been developing RiVax(TM) in a consortium effort between
academic and industrial partners under several separate NIAID and FDA
grants to DOR and UT Southwestern totaling approximately $15 Million. In
addition to UT Southwestern, development partners include, Stanford
Research Institute (SRI International), the University of Kansas, Lonza
Baltimore, and the Wadsworth Center of the New York State Department of
Health in Albany.
The development program, through UT Southwestern, has also been recently
awarded a $1 million FDA Orphan Products grant to carry out additional
clinical testing of RiVax(TM). Dr. Ellen Vitetta has also separately been
awarded a grant for $2.2 million over 5 years to conduct research in
fundamental areas to develop novel vaccine formulations and characterize
immune responses in small animals. The outcome of that novel research will
help support ongoing development of RiVax(TM).
RiVax(TM) is a recombinant subunit of the ricin toxin A chain and has been
genetically detoxified. The subunit is produced in recombinant bacterial
hosts, purified, and formulated for human and animal testing.
About Ricin Toxin
Ricin toxin is a potent plant toxin that can be easily produced from
abundantly available castor beans. There exists no vaccine to protect
against exposure nor post-exposure therapeutic other than supportive care.
Ricin toxin is highly toxic to humans and other mammals and is a thought to
be a bioterror threat because of its environmental stability and high
potency, second only to botulinum toxin as a natural toxin. Exposure to
small amounts can lead to lung damage if inhaled with rapid onset of
nausea, fever, and abdominal pain if ingested. General organ failure
leading to death can occur within several days. The need for protective
countermeasures against ricin toxin has been emphasized by its recent and
continued use as a biological weapon. The successful development of an
effective vaccine against ricin toxin may act as a deterrent in the actual
use of ricin as a biological weapon and could be used in rapid deployment
scenarios in the event of a biological attack.
About DOR BioPharma, Inc.
DOR BioPharma, Inc. (DOR) is a biopharmaceutical company developing
products to treat life-threatening side effects of cancer treatments and
serious gastrointestinal diseases, and vaccines for certain bioterrorism
agents. DOR's lead product, orBec® (oral beclomethasone dipropionate), is
a potent, locally acting corticosteroid being developed for the treatment
of GI GVHD, a common and potentially life-threatening complication of bone
marrow transplantation. DOR has filed an NDA for orBec® with the FDA for
the treatment of GI GVHD, and subsequent to supplemental information
recently submitted, the FDA has extended the PDUFA (Prescription Drug User
Fee Act) date to October 21, 2007. An MAA (Marketing Authorization
Application) with the EMEA (European Medicines Evaluation Agency) has also
been filed and validated. orBec® may also have application in treating
other gastrointestinal disorders characterized by severe inflammation. DOR
has also recently initiated a development program with its Lipid Polymer
Micelle (LPM(TM)) oral drug delivery technology for the oral delivery of
leuprolide for the treatment of prostate cancer and endometriosis.
Through its Biodefense Division, DOR is developing biomedical
countermeasures pursuant to the recently enacted Project BioShield Act of
2004. DOR's biodefense products in development are recombinant subunit
vaccines designed to protect against the lethal effects of exposure to
ricin toxin and botulinum toxin. DOR's ricin toxin vaccine, RiVax(TM), has
been shown to be safely tolerated and immunogenic in a Phase 1 clinical
trial in normal volunteers.
For further information regarding DOR BioPharma, please visit the Company's
website located at www.dorbiopharma.com.
This press release contains forward-looking statements, within the meaning
of Section 21E of the Securities Exchange Act of 1934, that reflect DOR
BioPharma, Inc.'s current expectations about its future results,
performance, prospects and opportunities, including statements regarding
the potential use of orBec® for the treatment of gastrointestinal GVHD
and the prospects for regulatory filings for orBec®. Where possible, DOR
has tried to identify these forward-looking statements by using words such
as "anticipates," "believes," "intends," or similar expressions. These
statements are subject to a number of risks, uncertainties and other
factors that could cause actual events or results in future periods to
differ materially from what is expressed in, or implied by, these
statements. DOR cannot assure you that it will be able to successfully
develop or commercialize products based on its technology, including
orBec®, particularly in light of the significant uncertainty inherent in
developing vaccines against bioterror threats, manufacturing and conducting
preclinical and clinical trials of vaccines, and obtaining regulatory
approvals, that its technologies will prove to be safe and effective, that
its cash expenditures will not exceed projected levels, that it will be
able to obtain future financing or funds when needed, that product
development and commercialization efforts will not be reduced or
discontinued due to difficulties or delays in clinical trials or due to
lack of progress or positive results from research and development efforts,
that it will be able to successfully obtain any further grants and awards,
maintain its existing grants which are subject to performance, enter into
any biodefense procurement contracts with the U.S. Government or other
countries, that the U.S. Congress may not pass any legislation that would
provide additional funding for the Project BioShield program, that it will
be able to patent, register or protect its technology from challenge and
products from competition or maintain or expand its license agreements with
its current licensors, or that its business strategy will be successful.
Important factors which may affect the future use of orBec® for
gastrointestinal GVHD include the risks that: because orBec® did not
achieve statistical significance in its primary endpoint in the pivotal
Phase 3 clinical study (i.e. a p-value of less than or equal to 0.05), the
Oncologic Drug Advisory Committee ("ODAC") appointed by the FDA voted that
the data supporting orBec® did not show substantial evidence of efficacy
by a margin of 7 to 2 for the treatment of GI GVHD, although the FDA is not
bound by ODAC's decision, the FDA may not consider orBec® approvable
based upon existing studies, orBec® may not show therapeutic effect or an
acceptable safety profile in future clinical trials, if required, or could
take a significantly longer time to gain regulatory approval than DOR
expects or may never gain approval; DOR is dependent on the expertise,
effort, priorities and contractual obligations of third parties in the
clinical trials, manufacturing, marketing, sales and distribution of its
products; or orBec® may not gain market acceptance; and others may
develop technologies or products superior to orBec®. These and other
factors are described from time to time in filings with the Securities and
Exchange Commission, including, but not limited to, DOR's most recent
reports on Form 10-QSB and Form 10-KSB. DOR assumes no obligation to update
or revise any forward-looking statements as a result of new information,
future events, and changes in circumstances or for any other reason.
Company Contact:
Evan Myrianthopoulos
Chief Financial Officer
(786) 425-3848
www.dorbiopharma.com
