Miravant's PhotoPoint PDT Arrests Tumor Growth by Destroying Tumor Blood Vessels.

Business Editors & Health/Medical Writers

SANTA BARBARA, Calif.--(BW HealthWire)--April 4, 2002

Preclinical Results Will Be Presented At Cancer Research

Meeting and Published in Prestigious Oncology Journal

Miravant Medical Technologies (Nasdaq:MRVT) a pharmaceutical development company specializing in PhotoPoint(TM) photodynamic therapy (PDT), announced today that results from preclinical oncology studies utilizing one of Miravant's new proprietary light-activated drug compounds will be presented at the American Association for Cancer Research (AACR), April 6-10, San Francisco. The studies were conducted at the Edwin L. Steele Laboratory for Tumor Biology, Massachusetts General Hospital, Boston, and will be presented by Dennis E. Dolmans, M.D., Assistant Professor Dai Fukumura, M.D., Ph.D. and Professor Rakesh K. Jain, Ph.D., Director of the Edwin L. Steele Laboratory and Professor of Tumor Biology. Additionally, earlier data from these studies were published this week as a cover article in the April issue of the prestigious journal, Cancer Research.

The preclinical studies were conducted in breast cancer models using PhotoPoint drug MV6401. PhotoPoint PDT demonstrated selective shutdown of tumor neovasculature (the new vascular networks that are essential to the growth and sustenance of all solid tumors) leading to tumor eradication or significant growth delay.

PhotoPoint PDT uses light-activated drugs to target diseased cells and blood vessels. Data to be presented at AACR demonstrate that PhotoPoint MV6401 selectively localizes to the neovasculature of orthotopic mammary tumors. Activation of the drug, with appropriate doses of light, results in selective shutdown and stasis (cessation of blood flow) of tumor neovasculature while sparing the surrounding normal blood vessels. This tumor neovessel stasis seems to occur in two phases: (1) an initial constriction followed by (2) a thrombosis (clot) formation resulting in vascular stasis. This selective tumor neovessel stasis correlates with death of the tumor cells and long-term cessation of tumor growth.

Dr. John S. Hill, Director of the Oncology Program at Miravant stated, "Therapies which target the blood supply and vessels of tumors and effect angiogenesis are currently an area of great scientific and clinical interest. We are excited by the very striking vascular targeting effects using PhotoPoint PDT and the resulting tumor destruction demonstrated by Professor Jain's research group at the Steele Laboratory." Dr. Hill added, "These results suggest we may be able to develop novel strategies for treating solid tumors with PhotoPoint PDT by destroying the tumor blood vessels."

Additional preclinical studies are in progress to further define the selective vascular effects of PhotoPoint PDT and to evaluate its efficacy in tumor eradication.

The abstract of these and other PhotoPoint studies are available at Miravant's website, www.miravant.com.

Miravant Medical Technologies specializes in both pharmaceuticals and devices for photoselective medicine. The company is developing its proprietary PhotoPoint photodynamic therapy (PDT) in ophthalmology, dermatology, cardiovascular disease and oncology. Miravant is investigating intravascular PhotoPoint PDT for the treatment of angioplasty-related restenosis and atherosclerosis.

The statements above by Dr. Hill and other statements about the potential use of PhotoPoint PDT to treat cancer tumors, selectively shutdown tumor neovasculature, destroy or eradicate tumors and significantly delay tumor growth, and additional tumor studies in progress to further evaluate the effects of PhotoPoint PDT are forward-looking and relate to our future plans, objectives, expectations and intentions. Our actual results may differ materially from those described in these statements. For instance, the occurrence of one or more of the following may cause our results to differ from our plans: the company's operating capital may not be sufficient to continue some or all of its development programs; potential future funding may not be available when needed if at all or under terms acceptable to the company; the company may decide not to further develop PhotoPoint PDT for tumor treatments; and the results of the preclinical studies of tumors may not be indicative of clinical results when and if the clinical trial process begins. For a discussion of additional important risk factors that may cause our results to differ from those described above, please refer to our annual report on Form 10-K for the year ended December 31, 2001 and other quarterly and periodic reports filed with the Securities and Exchange Commission.

For more information please visit our web site at: www.miravant.com.