Peregrine Pharmaceuticals Awarded Broad New U.S. Patent for Vascular Imaging Applications...

Peregrine Pharmaceuticals Awarded Broad New U.S. Patent for Vascular Imaging
Applications of Its PS-Targeting Platform

-- New Claims Cover Use of Phosphatidylserine-Targeting Antibodies to Image
Solid Tumors and Other Malignancies --

-- Supported by Published Data Showing Utility of PS-Targeting Antibodies for
the Molecular Imaging of Cancer --

TUSTIN, Calif., June 24 /PRNewswire-FirstCall/ -- Peregrine Pharmaceuticals,
Inc. (Nasdaq: PPHM) today reported the issuance of a U.S. patent with broad
claims covering vascular imaging applications for phosphatidylserine
(PS)-targeting antibodies. The patent represents the first broad coverage of
imaging claims under Peregrine's PS-targeting platform, which includes
Peregrine's lead antibody bavituximab. PS is a phospholipid that becomes
exposed on the surface of tumor blood vessel cells. Since PS is typically not
exposed on the surface of normal tissues, it represents a unique target for
the vascular imaging of tumors and tumor metastases in patients with cancer.

"PS-targeting antibodies such as bavituximab preferentially bind to tumor
blood vessels, which makes them ideal vehicles for imaging the tumor
vasculature," said Dr. Philip Thorpe, professor of pharmacology at UT
Southwestern Medical Center and a scientific advisor to Peregrine. "Last year
we published data from preclinical imaging studies confirming bavituximab's
high specificity for targeting tumor blood vessels with little or no
localization to normal tissue.(1) Bavituximab's ability to achieve unusually
clear images of tumors in living animals in these studies supports the concept
that PS-targeting antibodies may be useful for the non-invasive detection of
tumors and their metastases in cancer patients."

The new patent claims methods for imaging solid tumors using PS-targeting
antibodies coupled to a variety of imaging agents.

"Issuance of this broad vascular imaging patent expands the breadth of our
intellectual property around our PS-targeting platform," said Steven W. King,
president and CEO of Peregrine. "This patent protects expanded use of
bavituximab and other PS-targeting antibodies to track disease and treatment
status in cancer patients. The growing patent estate around our PS-targeting
technology provides us with new options and applications for leveraging our
PS-targeting antibodies."

Bavituximab, Peregrine's most advanced PS-targeting antibody, is currently
being tested in combination with chemotherapy in one Phase II trial in
advanced lung cancer and two Phase II trials in advanced breast cancer.
Interim data from these studies has been promising.

U.S. Patent #7,550,141, which was issued on June 23, 2009, was granted to the
University of Texas System and is exclusively licensed to Peregrine
Pharmaceuticals.

1. M Jennewein, M Lewis, D Zhao, E Tsyganov, N Slavine, J He, L Watkins, V
Kodibagkar, S O'Kelly, P Kulkarni, P Antich, A Hermanne, F Rosch, R Mason, P
Thorpe, Vascular Imaging of Solid Tumors in Rats with a Radioactive
Arsenic-Labeled Antibody that Binds Exposed Phosphatidylserine, Clinical
Cancer Research. March 1, 2008.

About Phosphatidylserine (PS)-Targeting Antibodies
The rapid and disorganized growth that is the hallmark of cancer results in
the exposure of the lipid phosphatidylserine (PS) on the surface of tumor
blood vessels. Since PS typically is not exposed on the surface of normal
tissues, it represents a unique target for cancer diagnostics and
therapeutics. Bavituximab is a monoclonal antibody that specifically targets
PS exposed on the surface of the cells lining tumor blood vessels. It
currently is in three Phase II clinical trials for the treatment of advanced
breast cancer and advanced lung cancer. Further information on the role of
exposed PS in the tumor environment can be found in the Anti-PS Technical
Backgrounder posted at www.peregrineinc.com.

About Peregrine Pharmaceuticals
Peregrine Pharmaceuticals, Inc. is a biopharmaceutical company with a
portfolio of innovative monoclonal antibodies in clinical trials for the
treatment of cancer and serious viral infections. The company is pursuing
three separate clinical programs in cancer and hepatitis C virus infection
with its lead product candidates bavituximab and Cotara(R). Peregrine also
has in-house manufacturing capabilities through its wholly owned subsidiary
Avid Bioservices, Inc. (www.avidbio.com), which provides development and
biomanufacturing 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 PS-targeting antibodies will not be useful for the non-invasive
imaging of tumors in cancer patients. 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 or otherwise adversely impact the company's ability to obtain
regulatory approval for its product candidates 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,
2008 and the quarterly report on Form 10-Q for the quarter ended January 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, both for
Peregrine Pharmaceuticals, Inc.