SAN DIEGO, Dec. 27 /PRNewswire-FirstCall/ -- ADVENTRX Pharmaceuticals, Inc. (Amex: ANX) today announced the initiation of a Phase II clinical trial using CoFactor(R) in the treatment of refractory metastatic breast cancer. CoFactor (ANX-510) is a folate-based biomodulator drug designed to enhance the activity and reduce associated toxicity of the widely used cancer chemotherapeutic agent 5-fluorouracil (5-FU).

This study builds on the results of earlier studies and will more fully investigate the efficacy and safety of CoFactor for patients with previously treated, advanced breast cancer.

"The initiation of this Phase II clinical trial for CoFactor represents an important milestone in the global registration strategy for our lead product development program," said Evan M. Levine, chief executive officer of ADVENTRX. "We are enthusiastic about CoFactor's potential to enhance the efficacy and safety of 5-FU chemotherapy in the treatment of refractory breast cancer."

"We are pleased to have launched this study of CoFactor in combination with 5-FU in advanced breast cancer," added James A. Merritt, MD, president and chief medical officer of ADVENTRX. "The CoFactor and 5-FU regimen has demonstrated activity in multiple tumor types, including breast in a Phase I clinical trial, and we have safety data from other CoFactor studies in metastatic colorectal cancer that suggest CoFactor is well-tolerated. We believe a CoFactor plus 5-FU regimen could offer a worthwhile alternative in the overall management of breast cancer."

This Phase II clinical trial is a single arm, multicenter study to evaluate the safety and efficacy of treatment with CoFactor plus 5-FU in advanced breast cancer patients who have failed anthracycline and taxane chemotherapies. Patients will be treated with CoFactor followed by 5-FU administered by IV bolus weekly for 6 weeks, with tumor and safety assessments every 8 weeks. The primary endpoint for the study is objective response rate (RECIST criteria), and secondary endpoints are duration of response, progression free survival, overall survival and incidence and severity of adverse events (AEs), as defined by the NCI Common Terminology Criteria. A total of 31 patients are expected to be enrolled at 6 clinical sites.

According to the American Cancer Society, breast cancer is the most frequently diagnosed cancer in American women and the second leading cause of cancer-related deaths in women after lung cancer. Over 214,000 new cases of breast cancer and over 41,000 deaths from breast cancer are expected in the US in 2006. Despite advances made in treatment options that have led to a significant increase in survival and quality of life, metastatic disease is still incurable. Five-year survival rates decrease with advancing disease stage: from 98% in localized disease to 80% with regional spreading to only 26% with metastatic disease.

About CoFactor

CoFactor (ANX-510) is a folate-based biomodulator drug designed to replace leucovorin to enhance the activity and reduce associated toxicity of the widely used cancer chemotherapy 5-fluorouracil (5-FU). In comparison to leucovorin, CoFactor creates more stable binding of the active form of 5-FU 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. In addition to the Phase II breast cancer trial, CoFactor is being studied in first-line treatment of metastatic colorectal cancer in a Phase IIb and pivotal Phase III clinical trial.

About ADVENTRX Pharmaceuticals

ADVENTRX Pharmaceuticals is a biopharmaceutical research and development company focused on commercializing low development risk pharmaceuticals for cancer and infectious disease that enhance the efficacy and/or safety of existing therapies. More information can be found on ADVENTRX's web site at www.adventrx.com.

Forward Looking Statement

ADVENTRX cautions you that statements included in this press release that are not a description of historical facts are forward-looking statements that involve risks, uncertainties, assumptions and other factors that, if they do not materialize or prove to be accurate, could cause ADVENTRX's results to differ materially from historical results or those expressed or implied by such forward-looking statements. Such forward-looking statements are made based on management's current expectations and beliefs and should not be regarded as a statement or representation by ADVENTRX that any of its plans, including its anticipated milestones, will be achieved on time or at all. The potential risks and uncertainties that could cause actual results to differ materially include, but are not limited to: the risk that ADVENTRX will be unable to raise sufficient capital to fund the projects necessary to meet its anticipated or stated goals and milestones; the potential to attract a strategic partner and the terms of any related transaction; the ability to timely enroll subjects in ADVENTRX's current and anticipated clinical trials; the results of pending clinical trials for CoFactor(R) or ADVENTRX's other product candidates; the potential for CoFactor(R) and ADVENTRX's other product candidates to receive regulatory approval for one or more indications on a timely basis or at all, and the uncertain process of seeking regulatory approval; other difficulties or delays in developing, testing, manufacturing and marketing of and obtaining regulatory approval for CoFactor(R) or ADVENTRX's other product candidates; the market potential for fluoropyrimidine biomodulators and other target markets, and ADVENTRX's ability to compete in those markets; unexpected adverse side effects or inadequate therapeutic efficacy of CoFactor(R) or ADVENTRX's other products that could delay or prevent regulatory approval or commercialization, or that could result in recalls or product liability claims; the risk that preclinical and clinical results are not indicative of the success of subsequent clinical trials and that products will not perform as preclinical and clinical data suggests or as otherwise anticipated; the potential for regulatory authorities to require additional preclinical work or other clinical requirements to support regulatory filings; the scope and validity of patent protection for CoFactor(R) and Adventrx' other product candidates; and other risks and uncertainties more fully described in ADVENTRX's press releases and periodic filings with the Securities and Exchange Commission. ADVENTRX's public filings with the Securities and Exchange Commission are available at http://www.sec.gov.

You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date when made. All forward-looking statements are qualified in their entirety by this cautionary statement and ADVENTRX assumes no obligation to revise or update any forward-looking statement, including as set forth in this press release, to reflect events or circumstances arising after the date on which it was made.

SOURCE ADVENTRX Pharmaceuticals, Inc.
12/27/2006

CONTACT: Ioana C. Hone of ADVENTRX Pharmaceuticals, Inc.,
+1-858-552-0866