OXiGENE Announces Combination Clinical Trial of CA4P in Patients with Advanced Ovarian Cancer; Vascular Targeting Agent will be Combined with Standard-of-Care Chemotherapeutic Regimen.

Business Editors/Health/Medical Writers

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WATERTOWN, Mass.--(BUSINESS WIRE)--June 9, 2003

Fourth Concurrent Clinical Trial of Company's Lead

Tumor-Starving Compound

OXiGENE, Inc. (NASDAQ: OXGN, XSSE: OXGN) announced today that its lead Vascular Targeting Agent (VTA), Combretastatin A4 Prodrug (CA4P), will be combined with two standard-of-care chemotherapy drugs in a new clinical trial involving patients with advanced ovarian cancer.

CA4P will be studied in combination with carboplatin and paclitaxel in a Phase I/II trial that is being launched at Mount Vernon Hospital in the United Kingdom. The trial protocol has been approved by the U.K.'s health regulatory authority, the Medicines Control Agency, as well as the hospital's Institutional Ethics Committee. The Phase I arm of the study, which will include roughly 30 patients, will assess the safety and tolerability of the combination and will establish the optimal dosing schedule. The Phase II arm, which is expected to include between 20 and 30 patients, will focus on collecting additional safety data and evaluating anti-tumor efficacy.

"While radiation, chemotherapy and surgery have enabled medical professionals to manage cancer more effectively, the fact remains that many solid tumors remain incurable," said the study's principal investigator, Gordon Rustin, M.D., director of the Department of Medical Oncology at Mount Vernon Hospital. "This trial presents an opportunity to study the most clinically advanced Vascular Targeting Agent - CA4P - with two drugs that are considered the established standard of chemotherapy treatment in ovarian cancer."

"Our drug development program continues to build momentum," said Fred Driscoll, OXiGENE's president and CEO. "Over the past 12 months, CA4P has progressed into four clinical trials in five distinct tumor types - anaplastic thyroid, head & neck, lung, prostate and, now, ovarian - which are expected to account for more than 445,000 new cancer cases in the U.S. in 2003. The breadth of clinical evaluation of CA4P truly reflects the level of interest in the compound as an anti-cancer therapy."

Ovarian cancer ranks second in the number of new cases per year among the gynecologic cancers, according to the American Cancer Society (ACS). However, ovarian cancer causes more deaths per year than any other cancer of the female reproductive system. The ACS estimates that, in 2003, 14,300 ovarian cancer deaths will occur in the U.S. and another 25,400 women will be diagnosed with the disease.

OXiGENE announced last week that the U.S. Food and Drug Administration (FDA) granted "fast track" designation to CA4P for the treatment of advanced anaplastic thyroid cancer (ATC). CA4P currently is being evaluated in a Phase II study of patients with this disease.

In addition to the Phase I/II trial announced today and the Phase II study of patients with ATC, CA4P is being evaluated in a Phase I/II combination study with radiotherapy in patients with malignancies of the lung, head & neck and prostate; and a Phase Ib combination study with carboplatin in patients with various solid tumors. Although the carboplatin trial is ongoing and patients are still receiving therapy, there is no further patient accrual as the study objectives have been achieved. The data already obtained from the carboplatin study is being used in the design of this new, more advanced trial combining CA4P with carboplatin and paclitaxel.

CA4P is the water-soluble prodrug of Combretastatin A4, a compound isolated from the African bush willow Combretum Caffrum. CA4P is designed to damage and destroy solid tumors by impeding the flow of blood that carries the oxygen and nutrients these tumors need to grow and thrive. Research suggests that CA4P works by disrupting the intricate network of endothelial cells lining the tumor blood vessels, in essence killing the tumor from the inside. In Phase I trials, CA4P demonstrated biological effect with a complete patient response in anaplastic thyroid carcinoma and a partial response in fibrosarcoma. Several other Phase I patients with colon, medullary thyroid and pancreatic cancer saw prolonged periods of disease stabilization.

About OXiGENE

OXiGENE is the world leader in the development of novel biopharmaceutical compounds called vascular targeting agents (VTAs), which are designed to block the flow of blood that supplies solid cancer tumors and other abnormal vasculature, while leaving healthy cells intact. The Company's VTAs may have application in the treatment of certain forms of ocular

disease and other conditions. OXiGENE's lead VTA, Combretastatin A4 Prodrug, has advanced into Phase II and combination clinical trials in cancer patients in the United States and Europe. Three other OXiGENE VTAs, OXi4503, OXi6197 and OXi8007, are in pre-clinical development. For more information about OXiGENE, visit www.oxigene.com.

Safe Harbor Statement

This news release about the Phase I/II combination trial of CA4P, carboplatin and paclitaxel contains "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. These statements include, but are not limited to: the number of patients expected to be enrolled in each arm of the study; the study's objectives; the expected number of new cases of lung, prostate, head & neck and ovarian cancer in the U.S. in 2003; the ability of OXiGENE's vascular targeting compounds to enhance the effectiveness of traditional cancer treatments; and the introduction of innovative therapies to attack cancer and other diseases. Any or all of the forward-looking statements in this press release may turn out to be wrong. They can be affected by inaccurate assumptions OXiGENE might make or by known or unknown risks and uncertainties, including, but not limited to: the early stage of product development; the ability to secure necessary patents; uncertainties as to the future success of ongoing and planned clinical trials; and the unproven safety and efficacy of products under development. Consequently, no forward-looking statement can be guaranteed, and actual results may vary materially. Additional information concerning factors that could cause actual results to materially differ from those in the forward-looking statements are contained in OXiGENE's reports to the Securities and Exchange Commission, including OXiGENE's 10-Q, 8-K and 10-K reports. However, OXiGENE undertakes no obligation to publicly update forward-looking statements, whether because of new information, future events or otherwise.