Patient Treatment Initiated in ADVENTRX International Phase IIb Metastatic Colorectal Cancer Trial.

SAN DIEGO -- ADVENTRX Pharmaceuticals, Inc. (AMEX:ANX) today announced it has initiated patient treatment in its international, 300-patient Phase IIb clinical trial to evaluate the safety and efficacy of the Company's lead drug candidate, CoFactor(TM), used in combination with 5-fluorouracil (5-FU) for the treatment of metastatic colorectal cancer.

The Company also announced that it has received the necessary regulatory and ethics approvals from the individual countries' regulatory agencies to initiate the trial in the United Kingdom, Germany, Romania, Serbia and India. These individual country approvals are required in addition to clearance from the Medicines and Healthcare products Regulatory Agency (MHRA), which ADVENTRX received in April 2005. Applications to conduct this trial in Croatia and Poland are pending.

"Based on the strength of earlier studies in which CoFactor has demonstrated enhanced antitumor activity with significantly lower associated systemic toxicity in colorectal cancer compared with historic leucovorin and 5-FU-based treatment regimens, we are moving into this Phase IIb trial as the next important step toward gaining market approval," said Evan M. Levine, president and CEO for ADVENTRX. "We believe that CoFactor could improve the quality of life of colorectal cancer patients and replace leucovorin as a part of the standard 5-FU backbone treatment for this cancer."

Professor James Cassidy, M.D., MBChB, MSc, FRCP, the principal investigator for the trial, is Professor of Oncology and Head of the Department of Cancer Research in the U.K. Department of Medical Oncology at the University of Glasgow in Glasgow, Scotland. He has published over 140 peer-reviewed articles in scientific and medical journals and has led high profile oncology clinical studies, including most recently, the X-ACT study which contributed to the U.S. Food and Drug Administration (FDA) approval of Xeloda(TM).

The approximate 300 patients in this multi-center, open label, randomized, controlled study will be randomized to receive either CoFactor plus 5-FU, or leucovorin plus 5-FU. The primary endpoint for this trial is defined as reduction of grade 3 or greater toxicity, as defined by the NCI Common Terminology Criteria for Adverse Events, version 3, in the CoFactor/5-FU arm, compared with the leucovorin/5-FU control arm. Secondary endpoints in the trial are response rate, time to tumor progression and quality of life.

ADVENTRX recently received clearance in the U.S. under a Special Protocol Assessment (SPA) to begin a Phase III pivotal study of CoFactor in metastatic colorectal cancer. The Company currently plans to file this year for clearance to initiate a European Union-based Phase III CoFactor study in pancreatic cancer.

About CoFactor

CoFactor (ANX-510) is a folate-based biomodulator drug developed to enhance the activity of the widely used cancer chemotherapeutic 5-FU. Data from previous clinical trials in Europe have demonstrated clinical benefit and improved overall median survival in patients with advanced tumors, including colorectal, pancreatic and breast. In comparison to leucovorin, CoFactor creates more stable binding of the active form of 5-FU, FdUMP, to the target enzyme, thymidylate synthase (TS). CoFactor bypasses the chemical pathway required by leucovorin to deliver the active form of folate, allowing 5-FU to work more effectively. This improves 5-FU performance and lowers toxicity. ADVENTRX is the exclusive licensee of this compound. More information on CoFactor can be found at http://www.adventrx.com/products/antic_cofactor.htm.

About ADVENTRX

ADVENTRX Pharmaceuticals is a biopharmaceutical research and development company focused on introducing new technologies for anticancer and antiviral treatments that improve the performance and safety of existing drugs, by addressing significant problems such as drug metabolism, toxicity, bioavailability or resistance. More information can be found on the Company's Web site at www.adventrx.com.

Forward-Looking Statement

This press release contains forward-looking statements within the meaning of the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995. Such statements are made based on management's current expectations and beliefs. Actual results may vary from those currently anticipated based upon a number of factors, including uncertainties inherent in the drug development process, the timing and success of clinical trials, the validity of research results, and the receipt of necessary approvals from the FDA and other regulatory agencies. For a discussion of such risks and uncertainties, which could cause actual results to differ from those contained in the forward-looking statements, see "Risk Factors" in the Company's last quarterly report on Form 10-Q, as well as other reports that the Company files from time to time with the Securities and Exchange Commission. All forward-looking statements are qualified in their entirety by this cautionary statement. The Company undertakes no obligation to release publicly any revisions, which may be made to reflect events or circumstances after the date hereof.