OXiGENE's ZYBRESTAT(TM) Reported to Have Anti-Leukemic Effects in Preclinical Studies Published in Blood

OXiGENE's ZYBRESTAT(TM) Reported to Have Anti-Leukemic Effects in Preclinical
Studies Published in Blood

Results Suggest Broader Clinical Potential for Novel Anti-Cancer Drug Candidate

WALTHAM, Mass.--(BUSINESS WIRE)--Nov. 28, 2007--Regulatory News:

    OXiGENE, Inc. (NASDAQ: OXGN, XSSE: OXGN), a clinical-stage,
biopharmaceutical company developing novel therapeutics to treat
cancer and eye diseases, today reported that its lead product
candidate, ZYBRESTAT(TM) (combretastatin A4 phosphate / CA4P),
demonstrated anti-leukemic effects in preclinical studies published
online and ahead of print on November 16, 2007 on the website of the
journal BLOOD.

    The publication, entitled "The microtubule targeting agent, CA4P,
regresses leukemic xenografts by disrupting interaction with vascular
cells and promoting mitochondrial-dependent cell death," by Isabelle
Petit, Shahin Rafii, M.D. and colleagues from the Weill Medical
College of Cornell University, is available online, ahead of print, at
http://bloodjournal.hematologylibrary.org/cgi/content/abstract/
blood-2007-05-089219v1. (Due to its length, this URL may need to be
copied/pasted into your Internet browser's address field. Remove the
extra space if one exists.) Dr. Rafii is the Arthur Belfer Professor
of Medicine and a Howard Hughes Medical Institute Investigator.

    The authors hypothesized that because adhesion of leukemic cells
to vascular cells may confer resistance to chemotherapeutic agents,
treatment with CA4P would promote leukemic cell death by disrupting
leukemic cell cytoskeletal stability and interfering with vascular
cell interactions. The results detailed in the paper demonstrate that
low and non-toxic doses of CA4P inhibited leukemic cell proliferation
in vitro and induced mitotic arrest and cell death. Furthermore, in
mouse models of human leukemia, CA4P prolonged survival without
inducing hematological toxicity, likely by inhibiting proliferation
and circulation of leukemic cells, and diminished the extent of
peri-vascular leukemic cell infiltrates. These anti-leukemic effects
were shown to be mediated by mitochondrial damage and down-regulation
of the cell-adhesion protein VCAM-1, without causing hematological
toxicities. Based on these results, the authors concluded that CA4P is
a promising agent for the treatment of acute leukemias and merits
further evaluation in combination with other chemotherapeutic agents."We are very encouraged by these results seen with ZYBRESTAT,
which point to new mechanisms and indicate that its clinical potential
could extend beyond solid tumors, where current clinical development
efforts are focused, into hematological malignancies," commented Dai
Chaplin, Head of Research and Development and Chief Scientific Officer
for OXiGENE. "With a greater understanding of ZYBRESTAT's mechanism of
action, OXiGENE believes that it is positioned to exploit the full
clinical potential of this novel therapeutic candidate."

    About ZYBRESTAT (combretastatin A4 phosphate / CA4P)

    ZYBRESTAT(TM) is currently being evaluated in a pivotal
registration study in anaplastic thyroid cancer (ATC) under a Special
Protocol Assessment agreement with the U.S. Food and Drug
Administration (FDA). OXiGENE believes that ZYBRESTAT is poised to
become the first therapeutic product in a novel class of
small-molecule drug candidates called vascular disrupting agents
(VDAs). Through interaction with vascular endothelial cell
cytoskeletal proteins, ZYBRESTAT selectively targets and collapses
tumor vasculature, thereby depriving the tumor of oxygen and causing
death of tumor cells. In clinical studies, ZYBRESTAT has demonstrated
potent and selective activity against tumor vasculature, as well as
clinical activity against ATC and other solid tumors.

    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 -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 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. 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 Form 10-K,
10-Q and 8-K reports. However, OXiGENE undertakes no obligation to
publicly update forward-looking statements, whether because of new
information, future events or otherwise. Please refer to our Annual
Report on Form 10-K for the fiscal year ended December 31, 2006. 

OXiGENE, Inc.
Investor Relations
Shari Annes, 650-888-0902
sannes@oxigene.com