Results Indicate Bioequivalent Pharmacokinetics With Reduced Risk of Hypersensitivity Reactions With ANX-514

SAN DIEGO, April 25 /PRNewswire-FirstCall/ -- ADVENTRX Pharmaceuticals, Inc. (Amex: ANX), a biopharmaceutical research and development company focused on commercializing proprietary product candidates for the treatment of cancer and infectious diseases, today announced positive results from preclinical pharmacokinetic testing of ANX-514 (docetaxel emulsion) in a well recognized animal model. The study results indicate bioequivalent pharmacokinetics between ANX-514 and the FDA-approved version of docetaxel, marketed under the brand name Taxotere(R). Furthermore, ANX-514, administered intravenously, did not cause hypersensitivity reactions in this study, as opposed to acute hypersensivity reactions observed following intravenous treatment with Taxotere. ANX-514 is a novel emulsion formulation of docetaxel, an agent for the treatment of breast, non-small cell lung, prostate and gastric cancers.

"These preclinical results are important and strengthen our belief that ANX-514 is an appropriate candidate for marketing approval under the shorter timelines available under Section 505(b)(2)," said Evan M. Levine, chief executive officer for ADVENTRX. "In addition, these results suggest that treatment with ANX-514 may eliminate the need for multi-day premedication with corticosteroids prior to treatment, which is currently recommended prior to treatment with Taxotere."

In this study, docetaxel concentration in plasma was sequentially measured over 24 hours following intravenous injections with either ANX-514 or Taxotere. Pharmacokinetic analysis indicated no statistically significant (p < 0.05) differences in docetaxel maximum concentration (Cmax) or area under the curve (AUC) between ANX-514 and Taxotere. In addition, less toxicity was observed following dosing with ANX-514 than dosing with Taxotere. Taxotere induced an anaphylactoid type reaction consistent with hypersensitivity reactions, including acute increases in blood histamine levels and decreased blood pressure. In contrast, no hypersensitivity reactions, including no elevations in histamine levels and no changes in blood pressure were observed following dosing with ANX-514.

ADVENTRX is continuing to conduct additional preclinical pharmacokinetic testing of ANX-514 to compare this product candidate with the approved version of the product, marketed under the brand name Taxotere. The Company currently plans to seek guidance from the FDA with respect to the appropriateness of a Section 505(b)(2) NDA regulatory path for ANX-514, and pending agreement on clinical protocol design with the FDA, initiate a marketing-enabling clinical trial of ANX-514 in 2007.

About ANX-514 (docetaxel emulsion)

ANX-514 is a novel nano-emulsion formulation of the chemotherapy drug docetaxel, a product marketed under the brand name Taxotere. ANX-514 is designed to eliminate the need for multi-day immunosuppressant premedication. ANX-514 is formulated without polysorbate 80 or other detergents and is intended to reduce the severity and/or incidence of hypersensitivity reactions. Docetaxel is an anti-cancer agent that acts by disrupting the cellular microtubular network that is essential for cell division. Immunosuppressant premedication is recommended for docetaxel therapy to reduce the incidence and severity of allergic reactions. Docetaxel is approved to treat breast, non-small cell lung, prostate, gastric and head and neck cancers. In connection with a Section 505(b)(2) NDA covering ANX-514, ADVENTRX must certify that all applicable Taxotere patents have expired prior to the manufacture, use or sale of ANX-514.

About Section 505(b)(2)

Section 505(b)(2) of the U.S. Food, Drug & Cosmetic Act (FDCA) allows the Food and Drug Administration (FDA) to approve a follow-on drug on the basis of data in the scientific literature or conclusions regarding safety or effectiveness made by the FDA in the approval of other drugs. This regulatory pathway potentially makes it easier for drug manufacturers to obtain rapid approval of new forms of drugs based on the FDA's approval of the original drug. Some examples of products that may be allowed to follow a 505(b)(2) path to approval are drugs that have a new dosage form, strength, route of administration, formulation or indication. Upon approval, a drug may be marketed only for the FDA-approved indications in the approved dosage forms. Further clinical trials are necessary to gain approval for the use of the product for any additional indications or dosage forms.

About ADVENTRX Pharmaceuticals

ADVENTRX Pharmaceuticals is a biopharmaceutical research and development company focused on commercializing proprietary product candidates for the treatment of cancer and infectious diseases. The Company seeks to improve the performance and safety of existing treatments by addressing significant problems such as drug metabolism, bioavailability, excessive toxicity and treatment resistance. More information can be found on the Company's web site at http://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. These risks and uncertainties include, but are not limited to: 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 FDA's views on the appropriateness of seeking marketing approval of ANX-514 under Section 505(b)(2); difficulties or delays in developing, testing, manufacturing and marketing and obtaining regulatory approval for ANX-514, including receiving necessary regulatory approvals for clinical trials of ANX-514 and the potential for automatic injunctions regarding FDA approval of ANX-514 and other challenges by patent holders during the Section 505(b)(2) process; uncertainty under Section 505(b)(2) resulting from legal action against the FDA and the potential that future interpretations of Section 505(b)(2) could delay or prevent the FDA from approving any Section 505(b)(2) NDA; the potential for regulatory authorities to require additional preclinical work or other clinical requirements to support regulatory filings; patent and non-patent exclusivity covering docetaxel; 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, including funding the continued development of ANX-514; 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. 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. - 04/25/2007

CONTACT:
Investors, Ioana C. Hone of ADVENTRX Pharmaceuticals, +1-858-552-0866; or
Media, Amy Martini of WeissComm Partners, +1-212-301-7223, for ADVENTRX Pharmaceuticals, Inc.

Web site: http://www.adventrx.com