PRNewswire - November 2, 2004

-- Data Presented at 44th Annual Interscience Conference on Antimicrobial Agents and Chemotherapy

ROCKVILLE, Md., Nov. 2 /PRNewswire-FirstCall/ -- Human Genome Sciences, Inc. (Nasdaq: HGSI) today announced that it has identified and characterized a panel of thirty-eight novel monoclonal antibodies, including fifteen fully human monoclonal antibodies, for their ability to bind the CCR5 receptor and to inhibit CCR5-dependent infection by HIV-1 (human immunodeficiency virus).

The data were presented at the 44th Annual Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC), which ends today in Washington, DC (October 30-November 2, 2004). The company also announced that it has selected one of the CCR5 human monoclonal antibodies to evaluate further for its anti-HIV/AIDS properties.

A poster presented on Saturday, October 30, 2004, entitled "Characterization of a Panel of Novel Human Monoclonal Antibodies that Specifically Antagonize CCR5 and Block HIV-1 Entry" (Abstract #2871)(1), described the generation, characterization and HIV-1 inhibitory activity of thirty-eight individual monoclonal antibodies that specifically bind CCR5. Fifteen of the antibodies were produced from XenoMice (Abgenix), which are genetically engineered mice that generate fully human monoclonal antibodies.

Twenty-three were traditional mouse monoclonal (or murine) antibodies produced from BALB/c mice. The thirty-eight monoclonal antibodies were purified and then characterized for their ability to bind CCR5, block ligand binding, and inhibit CCR5-dependent HIV-1 infection. Characterization of the monoclonal antibodies revealed a range in their ability to bind cell- and membrane-bound CCR5 and to inhibit ligand binding. Evaluation of the antibodies for their ability to block HIV-1 entry in a single-round infection assay demonstrated that a number of the monoclonal antibodies were capable of blocking HIV-1 infection. Ultimately, one fully human monoclonal antibody, identified in the poster as CCR5mAb004, was observed to demonstrate the most potent inhibition of HIV-1 entry among the thirty-eight antibodies comprising the panel.

Additional characterization elucidated a number of attributes that support the continued development of the human monoclonal antibody, CCR5mAb004, including highly potent inhibition of CCR5-dependent entry of HIV-1 viruses representative of clades A-G, inhibition of T20-resistant HIV-1, inhibition of ligand binding, and inhibition of cell-cell fusion and viral transmission. It was also demonstrated that CCR5mAb004 does not induce signaling or mediate any cell toxicity upon binding CCR5. CCR5mAb004 displays a serum half-life of approximately nine days and bioavailability in mice following subcutaneous administration of ninety percent.

For more information about Human Genome Sciences, please visit the company's web site, http://www.hgsi.com. Health professionals interested in more information about trials involving HGSI products are encouraged to inquire via the Contact Us section of the Human Genome Sciences web site, http://www.hgsi.com/products/request.html, or by calling (240) 314-4400, extension 3550.

Human Genome Sciences is a company with the mission to treat and cure disease by bringing new gene-based protein and antibody drugs to patients. HGS and Human Genome Sciences are trademarks of Human Genome Sciences, Inc.

This announcement contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. The forward-looking statements are based on Human Genome Sciences' current intent, belief and expectations. These statements are not guarantees of future performance and are subject to certain risks and uncertainties that are difficult to predict. Actual results may differ materially from these forward-looking statements because of the Company's unproven business model, its dependence on new technologies, the uncertainty and timing of clinical trials, the Company's ability to develop and commercialize products, its dependence on collaborators for services and revenue, its substantial indebtedness and lease obligations, its changing requirements and costs associated with planned facilities, intense competition, the uncertainty of patent and intellectual property protection, the Company's dependence on key management and key suppliers, the uncertainty of regulation of products, the impact of future alliances or transactions and other risks described in the Company's filings with the Securities and Exchange Commission. Existing and prospective investors are cautioned not to place undue reliance on these forward-looking statements, which speak only as of today's date. Human Genome Sciences undertakes no obligation to update or revise the information contained in this announcement whether as a result of new information, future events or circumstances or otherwise.

Footnotes:

(1) Roschke V, Moore PA, et al. Characterization of a Panel of Novel Human Monoclonal Antibodies that Specifically Antagonize CCR5 and Block HIV-1 Entry. 44th Annual Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC), 2004: Abstract #2871.

SOURCE Human Genome Sciences, Inc.

Web Site: http://www.hgsi.com/

041102
PR041105

Always watch for outdated information. This article first appeared in 2004. This material is designed to support, not replace, the relationship that exists between you and your doctor.

AEGiS presents published material, reprinted with permission and neither endorses nor opposes any material. All information contained on this website, including information relating to health conditions, products, and treatments, is for informational purposes only. It is often presented in summary or aggregate form. It is not meant to be a substitute for the advice provided by your own physician or other medical professionals. Always discuss treatment options with a doctor who specializes in treating HIV.

Copyright ©1980, 2004. AEGiS. All materials appearing on AEGiS are protected by copyright as a collective work or compilation under U.S. copyright and other laws and are the property of AEGiS, or the party credited as the provider of the content. .