Pipex Pharmaceuticals Announces Issuance of Additional US Patent Covering CD4 Inhibitor Molecules

ANN ARBOR, MI , a specialty pharmaceutical company developing innovative late-stage drug candidates for the treatment of neurologic and autoimmune diseases, announced it was issued a United States patent that is part of its CD4 inhibitor patent estate. The issued patent, U.S. 7,345,020, entitled, "Mimetics of CD4 That Inhibit Immune Responses," covers new chemical entities relating to inhibitors of the highly studied CD4 T-cell receptor, a key protein in T-cell-Antigen Presenting Cell immunological synapse formation and T-cell activation critical in so-called CD4-mediated diseases such as transplantation, multiple sclerosis (MS), psoriasis, and rheumatoid arthritis (RA).

"This patent issuance supplements our intellectual property estate which now constitutes over 40 issued and pending patent applications such as issued U.S. patent 6,127,387 and pending international equivalents that broadly claim the use of any small molecule to specifically inhibit the highly immunologically relevant CD4 T-cell receptor as well as issued U.S. patent 6,844,421 and issued and pending international equivalents that claim the composition-of-matter of our lead anti-CD4 802-2 peptidomimetic nearing completion of a Phase I/II clinical trial in the U.S. for graft-vs.-host disease (GVHD)," said Steve H. Kanzer, CPA, JD, Pipex's Chairman and CEO.

He added, "We believe that our rationally designed small molecule and peptidomimetic anti-CD4 intellectual property estate broadly covers this important next generation approach toward the goal of accomplishing immune tolerance that is selective for activated (as opposed to resting) T-cells thus avoiding the highly limiting broad T-cell depleting effects and corresponding immunosuppression associated with previous approaches utilizing monoclonal antibodies. The therapeutic market for CD4-mediated diseases and the goal of treating these diseases with disease modifying approaches capable of selectively and conveniently inducing immune tolerance is considerable and includes acute indications such as transplantation and chronic autoimmune diseases such as multiple sclerosis (MS), psoriasis, and rheumatoid arthritis (RA)."

Pipex's CD4 inhibitors were developed by using computer-aided, rational drug design technologies and are proteolytically stable, water-soluble cyclic molecules that are designed to specifically bind to and inhibit a surface-binding pocket of the CD4 transmembrane glycoprotein receptor. This surface pocket is believed to be critical to the interaction and oligomerization of CD4, with major histocompatibility complex class II (MHC class II) providing the necessary focused threshold T cell receptor (TCR) and P56 (LCK) signaling required for the initiation of activation of CD4+ T cells. By preventing threshold signaling, the Company's CD4 inhibitors have demonstrated the important added immunological advantage of selectively causing apoptosis and/or anergy, thus effectively causing permanent deletion and/or long-term deactivation of "activated" or "flaring" CD4+ T cells. Pipex's lead CD4 inhibitor, 802-2, appears to be immunoselective and non-T cell-depleting, nor does it have any observable effect on resting CD4+ T cells or CD8+ T cells which might otherwise cause immunosuppressive side effects. 802-2 and Pipex's small molecule CD4 inhibitors have demonstrated oral activity, an additional important potential advantage over monoclonal antibody and biologic approaches.

Through a majority-owned subsidiary, CD4 Biosciences, Inc., Pipex has obtained exclusive licenses to these patents from Thomas Jefferson University.

An informative animation describing the structure and function of Pipex's Anti-CD4 programs can be viewed at the following link: http://www.pipexpharma.com/pipeline.php?pageID=9.

About Pipex Pharmaceuticals, Inc.

Pipex Pharmaceuticals, Inc. ("Pipex") is a specialty pharmaceutical company that is developing four proprietary, late-stage drug candidates for the treatment of neurologic and fibrotic diseases. Pipex's strategy is to exclusively in-license proprietary, clinical-stage drug candidates and to complete the further clinical testing, manufacturing and regulatory requirements sufficient to seek marketing authorizations via the filing of New Drug Applications (NDAs). Pipex's drug candidates address the following market opportunities: Multiple Sclerosis (MS), Dry Age-Related Macular Degeneration (AMD), Fibromyalgia, Alzheimer's disease and Idiopathic Pulmonary Fibrosis. For further information please visit www.pipexinc.com.

This release contains forward-looking statements within the meaning of Section 21E of the Securities Exchange Act of 1934, as amended, including statements regarding Pipex's plans for its product candidates. Words such as, but not limited to, "look forward to," "believe," "expect," "anticipate," "estimate," "intend," "plan," "targets," "likely," "will," "would," "should," and "could," and similar expressions or words identify forward-looking statements. Such forward-looking statements are based upon current expectations that involve risks, changes in circumstances, assumptions and uncertainties. Pipex is at an early stage of development and may not ever have any products that generate significant revenue. Important factors that could cause actual results to differ materially from those reflected in Pipex's forward-looking statements include, among others, a failure of Pipex's product candidates to be demonstrably safe and effective, a failure to obtain regulatory approval for the company's products or to comply with ongoing regulatory requirements, a lack of acceptance of Pipex's product candidates in the marketplace, a failure of the company to become or remain profitable, Pipex's inability to obtain the capital necessary to fund its research and development activities, a loss of any of the company's key scientists or management personnel, and other factors described in Pipex's report on Form 10-K for the year ended December 31, 2007. No forward-looking statements can be guaranteed and actual results may differ materially from such statements. The information in this release is provided only as of the date of this release, and Pipex undertakes no obligation to update any forward-looking statements contained in this release on account of new information, future events, or otherwise, except as required by law.

For Further Information Contact: Steve H. Kanzer, CPA, Esq. Chairman and Chief Executive Officer [phone] Thomas Redington Investor Relations Redington, Inc. [phone]