Peregrine Pharmaceuticals Awarded Second Broad U.S. Patent for Anti-Viral Applications of Phospholipid-Targeting Antibodies

Peregrine Pharmaceuticals Awarded Second Broad U.S. Patent for Anti-Viral
Applications of Phospholipid-Targeting Antibodies
--Broad New Patent Covers Peregrine's Lead PS-Targeting Antibody Bavituximab
and Similar Agents for the Treatment of All Viral Infections--

TUSTIN, Calif., Nov. 4 /PRNewswire-FirstCall/ -- Peregrine Pharmaceuticals,
Inc. (Nasdaq: PPHMD) today announced that the U.S. Patent and Trademark Office
has issued U.S. Patent Number 7,611,704, which includes broad claims covering
anti-viral uses of phosphatidylserine (PS)-targeting antibodies including
Peregrine's lead clinical compound, bavituximab. PS is a unique marker
exposed on the surface of virally infected cells that can be targeted to treat
a broad spectrum of virus infections.

The new patent covers compositions and methods of treating virus infections
using bavituximab and similar antibodies, either alone or as immunoconjugates
attached to anti-viral agents, as well as in combination with other anti-viral
agents. The breadth of the claims in the new patent is especially noteworthy
since it includes methods for treating all viruses in humans and in animals.
The therapeutic potential of these antibodies is supported by data in a
landmark study published in the December 2008 edition of Nature Medicine
showing that bavituximab and other PS-targeting antibodies have the potential
to cure lethal virus infections across a broad range of virus families in
animal disease models.

"This broad anti-viral patent further expands our intellectual property
leadership in the field of PS-targeting antibodies at a time when our
anti-viral program is experiencing a rising tide of interest and activity,"
said Steven W. King, president and CEO of Peregrine. "We are especially
pleased at the scope of the issued claims in this new patent, which covers the
use of bavituximab and similar antibodies in the treatment of any and all
virus infections. Antibodies falling under the scope of this new patent have
already demonstrated promising anti-viral activity in clinical trials in
patients with hepatitis C virus (HCV) infection and are the focus of our
ongoing research funded by a Transformational Medical Technologies Initiative
contract to study the potential of these agents as broad spectrum viral
hemorrhagic fever therapeutics."

PS, a lipid molecule normally found only on the inside of cell membranes,
becomes exposed on the outside of the membranes of viruses and virally
infected cells. A rapidly growing body of published scientific research
confirms that exposed PS is directly involved in the pathogenesis of many
serious infectious diseases. Exposed PS enables viruses to evade immune
recognition and dampens the body's normal responses to infection. By masking
the exposed PS, PS-targeting antibodies are believed to block these effects,
allowing the body to develop a robust immune response to the pathogen.

Peregrine's PS-targeting antibodies have been shown to help clear infectious
virus from the bloodstream and to induce antibody-dependent cellular
cytotoxicity. PS is exposed on the outer membrane of cells infected with a
wide range of viruses, including HIV, influenza, herpes simplex viruses,
hemorrhagic fever viruses, cytomegalovirus (CMV), measles and members of the
smallpox and rabies virus families. Targeting PS thus provides a broad
platform for treating viral infections. Because the PS target is host-derived
rather than pathogen-derived, PS-targeting antibodies are also expected to be
much less susceptible to the viral genomic mutations that lead to anti-viral
drug resistance.

Bavituximab, which is Peregrine's most advanced PS-targeting antibody, is
currently being studied in a clinical trial for the treatment of patients
co-infected with HCV and HIV. Phase I studies in HCV patients showed that
bavituximab was well tolerated and it exhibited encouraging signs of
anti-viral activity.

Under a major biodefense initiative funded by the Defense Threat Reduction
Agency for the Transformational Medical Technologies Initiative (TMTI),
bavituximab and similar antibodies are in preclinical development for the
treatment of viral hemorrhagic fevers under a contract worth up to $44.4
million. Peregrine's work on viral hemorrhagic fevers is completely funded by
the TMTI under contract HDTRA1-08-C-0003.

This new patent was granted to The University of Texas System and is
exclusively licensed to Peregrine Pharmaceuticals.

About Peregrine Pharmaceuticals
Peregrine Pharmaceuticals, Inc. is a biopharmaceutical company with a
portfolio of innovative product candidates in clinical trials for the
treatment of cancer and serious virus infections. The company is pursuing
three separate clinical programs in cancer and HCV infection with its lead
product candidates bavituximab and Cotara®. Peregrine also has in-house
manufacturing capabilities through its wholly owned subsidiary Avid
Bioservices, Inc. (www.avidbio.com), which provides development and
bio-manufacturing services for both Peregrine and outside customers.
Additional information about Peregrine can be found at www.peregrineinc.com.

Safe Harbor Statement: Statements in this press release which are not purely
historical, including statements regarding Peregrine Pharmaceuticals'
intentions, hopes, beliefs, expectations, representations, projections, plans
or predictions of the future are forward-looking statements within the meaning
of the Private Securities Litigation Reform Act of 1995. The forward-looking
statements involve risks and uncertainties including, but not limited to, the
risk that the Company will not receive the full $44.4 million awarded under
the TMTI program, the risk that bavituximab will not achieve broad-spectrum
anti-viral effects and the risk that PS-targeting antibodies will not be less
susceptible to viral mutations. It is important to note that the company's
actual results could differ materially from those in any such forward-looking
statements. Factors that could cause actual results to differ materially
include, but are not limited to, uncertainties associated with completing
preclinical and clinical trials for our technologies; the early stage of
product development; the significant costs to develop our products as all of
our products are currently in development, preclinical studies or clinical
trials; obtaining additional financing to support our operations and the
development of our products; obtaining regulatory approval for our
technologies; anticipated timing of regulatory filings and the potential
success in gaining regulatory approval and complying with governmental
regulations applicable to our business. Our business could be affected by a
number of other factors, including the risk factors listed from time to time
in the company's SEC reports including, but not limited to, the annual report
on Form 10-K for the year ended April 30, 2009 and the quarterly report on
Form 10-Q for the quarter ended July 31, 2009. The company cautions investors
not to place undue reliance on the forward-looking statements contained in
this press release. Peregrine Pharmaceuticals, Inc. disclaims any obligation,
and does not undertake to update or revise any forward-looking statements in
this press release

Contacts:
GendeLLindheim BioCom Partners
Investors Media
info@peregrineinc.com Barbara Lindheim
(800) 987-8256 (212) 918-4650

SOURCE Peregrine Pharmaceuticals, Inc.

Investors, GendeLLindheim BioCom Partners, 1-800-987-8256,
info@peregrineinc.com; or Media, Barbara Lindheim, +1-212-918-4650, for
Peregrine Pharmaceuticals, Inc.