ImmuneRegen Announces Additional Rounds Of Testing In Anthrax Treatment Study

ImmuneRegen
BioSciences, Inc., a wholly owned subsidiary of IR BioSciences Holdings,
Inc. (OTC Bulletin Board: IRBO), today announced the results of their
preliminary round of testing on mice of its proprietary compound,
Viprovex(TM), as a possible treatment for pulmonary anthrax infection.
ImmuneRegen collaborated with Hyperion Biotechnology Inc. to perform these
tests at Hyperion's research facility located on the United States Air
Force School of Aerospace Medicine (USAFSAM) campus in Brooks City-Base,
Texas. Both companies have agreed to move forward with additional rounds of
testing on mice based on the results from the preliminary round.


These preliminary tests revealed a dose-dependent inhibition of
lethality due to anthrax spore inhalation in Viprovex-treated mice. Data
showed that Viprovex protected up to fifty percent of the animals exposed
to approximately LD50 concentrations of spores. Subsequent investigations
into potential underlying mechanisms revealed effects of Viprovex on
components of both the innate and acquired immune systems of test mice.
Real-time PCR studies revealed concentration-specific elevations in
cytokine and other immunomodulator transcripts following Viprovex exposure.
The Companies are planning further studies to better define the
capabilities and mechanisms of Viprovex in animal models of pulmonary
anthrax infection.


About Viprovex


Viprovex is the trade name used in referring to formulations of
Homspera for potential indications for treatment of maladies caused by
exposure to various chemical and biological agents. Homspera is a generic
name used by the Company to describe the synthetic peptide Sar9, Met
(O2)11-Substance P. Sar9, Met (O2)11-Substance P is an analog of the
naturally occurring human neuropeptide Substance P, which can be found
throughout the body, including in the airways of humans and many other
species. All of the Company's research and development efforts are early,
pre-clinical stage and both Homspera and Viprovex have only undergone
exploratory studies to evaluate their biological activity in small animals.


About Hyperion


Hyperion Biotechnology was founded in 1998 and has active programs in
the area of biomarker discovery, wound healing, performance enhancement,
infectious disease treatment and other homeland security related topics.
These research efforts have been funded by contracts with the Department of
Defense (DoD).


About ImmuneRegen BioSciences, Inc.


IR BioSciences Holdings Inc., through its wholly owned subsidiary
ImmuneRegen BioSciences, Inc., is a development stage biotechnology company
focused on the research and development of Homspera(TM) and its derivatives
Radilex(TM) and Viprovex(TM), which are designed to be used as
countermeasures for multiple homeland security bioterrorism threats.
Homspera is derived from modified Substance P, a naturally occurring
peptide immunomodulator and homeostatic compound with the dual effect of
improving pulmonary function and the stimulation of the human immune
system. For more information, please visit the company's website at
immuneregen.















Statements about the Company's future expectations, including
statements about the potential for the Company's drug candidates, science
and technology, and all other statements in this press release other than
historical facts, are "forward-looking statements" within the meaning of
Section 27A of the Securities Act of 1933, Section 21E of the Securities
Exchange Act of 1934, and as that term is defined in the Private Securities
Litigation Reform Act of 1995. The Company intends that such
forward-looking statements be subject to the safe harbors created thereby.
These future events may not occur as and when expected, if at all, and,
together with the Company's business, are subject to various risks and
uncertainties. The Company's actual results could differ materially from
expected results as a result of a number of factors, including the fact
that preliminary results involved only a small number of test mice, the
subsequent investigations were limited in scope, the uncertainties inherent
in research and development collaborations, pre-clinical and clinical
trials and product development programs, (including, but not limited to the
fact that future results or research and development efforts may prove less
encouraging than current results or cause side effects not observed in
current pre-clinical trials) the evaluation of potential opportunities, the
level of corporate expenditures, capital market conditions, and others set
forth in the Company's periodic report on Form 10-QSB for the three months
ended March 31, 2006 and on Form 10-KSB for the twelve months ended
December 31, 2005 as filed with the Securities and Exchange Commission.
There are no guarantees that any of the Company's proposed products will
prove to be commercially successful. The Company undertakes no duty to
update forward-looking statements.


ImmuneRegen BioSciences, Inc.

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