OXiGENE Announces Publication of Preclinical Data on OXi4503 Demonstrating Potent Anti-Leukemic Effects

SOUTH SAN FRANCISCO, Calif., May 27, 2010 (GLOBE NEWSWIRE) -- OXiGENE, Inc.
(Nasdaq:OXGN) (Stockholm:OXGN), a clinical-stage, biopharmaceutical company
developing novel therapeutics to treat cancer and eye diseases, announced
publication of preclinical data on its second-generation, dual-action vascular
disrupting agent (VDA) OXi4503 that demonstrate potent activity against acute
myeloid leukemia (AML). The data were published in Blood in an article
entitled, "Leukemia regression by vascular disruption and anti-angiogenic
therapy" by Gerard Madlambayan, Christopher Cogle and colleagues from the
Department of Medicine and Program in Stem Cell Biology at the University of
Florida in Gainesville, Florida. The data are available online, ahead of print
on the Blood website:
http://bloodjournal.hematologylibrary.org/cgi/reprint/blood-2009-06-230474v1. 

In these studies researchers administered OXi4503 to mice that were carriers of
human AML, which serve as models of human AML, including a subcutaneous model
and an orthotopic model of primary human AML, which were then studied for
disease regression. The data show that OXi4503 produced remissions in AML of
differing subtypes, including those with activating mutations in subtype FLT3.
The investigators further demonstrated that the potent anti-leukemic effects of
OXi4503 resulted from the combination of two effects: 1) vascular disruption,
which interferes with endothelial cell interactions with leukemia, and 2)
direct cytotoxic effects on leukemia cells via generation of intracellular
reactive oxygen species (ROS). The authors concluded that OXi4503 may represent
a promising therapeutic agent, including for patients with high risk AML. 

"We continue to be very encouraged by the antitumor effects of OXi4503,
especially the indications that its unique dual action mechanism may underlie
its particularly potent activity in certain cancer types, including high-risk
AML," commented Dai Chaplin, Ph.D., OXiGENE's Chief Scientific Officer. "We
believe that OXi4503 has significant potential in a range of solid tumors and
leukemias. We intend to continue to explore ways to optimize its potential in
AML and other forms of leukemia, including initiation of clinical evaluation of
OXi4503 in AML later in 2010." 

About OXi4503

OXi4503 (combretastatin A1 di-phosphate / CA1P) is a dual-mechanism vascular
disrupting agent (VDA) that is being developed in clinical trials for the
treatment of solid tumors. Like its structural analog, ZYBRESTAT™
(fosbretabulin / CA4P), OXi4503 has been observed to block and destroy tumor
vasculature, resulting in extensive tumor cell death and necrosis. In addition,
preclinical data indicate that OXi4503 is metabolized by oxidative enzymes
(e.g., tyrosinase and peroxidases), which are elevated in many solid tumors and
tumor white blood cell infiltrates, to an orthoquinone chemical species that
has direct cytotoxic effects on tumor cells. Preclinical studies have shown
that OXi4503 has (1) single-agent activity against a range of xenograft tumor
models; and (2) synergistic or additive effects when incorporated in various
combination regimens with chemotherapy, molecularly-targeted therapies
(including tumor-angiogenesis inhibitors), and radiation therapy. OXi4503 is
currently being evaluated as a monotherapy in a Phase 1 dose-escalation trial
in patients with advanced solid tumors and in patients with hepatic tumor
burden. 

About OXiGENE

OXiGENE is a clinical-stage biopharmaceutical company developing novel
therapeutics to treat cancer and eye diseases. The Company's major focus is
developing vascular disrupting agents (VDAs) that selectively disrupt abnormal
blood vessels associated with solid tumor progression and visual impairment.
OXiGENE is dedicated to leveraging its intellectual property and therapeutic
development expertise to bring life-extending and life-enhancing medicines to
patients. 

Safe Harbor Statement

This news release contains "forward-looking statements" within the meaning of
the Private Securities Litigation Reform Act of 1995. Any or all of the
forward-looking statements in this press release, which include OXiGENE's
expected initiation, progress, conclusion and reporting on clinical studies and
the effectiveness of OXi4503 in treating solid or liquid tumors may turn out to
be wrong. Forward-looking statements can be affected by inaccurate assumptions
OXiGENE might make or by known or unknown risks and uncertainties, including,
but not limited to, outcomes or timing of reporting final results from the
ongoing Cancer Research United Kingdom sponsored Phase 1 clinical trial of
OXi4503 in patients with advanced solid tumors, timing or outcomes of any
studies to be initiated in other oncology patients, including but not limited
to patients with leukemias, including AML, and the company's continued ability
to access additional capital. Additional information concerning factors that
could cause actual results to materially differ from those in the
forward-looking statements is contained in OXiGENE's reports to the Securities
and Exchange Commission, including OXiGENE's reports on Form 10-K and  10-Q.
However, OXiGENE undertakes no obligation to publicly update forward-looking
statements. 

CONTACT:  OXiGENE, Inc.
          Investor and Media Contact:
          Michelle Edwards, Investor Relations
          650-635-7006
          medwards@oxigene.com