Orchestra Therapeutics Announces New Phase II Clinical Data on NeuroVax(TM) Demonstrating Marked Expansion of Regulatory T Cell Populations in Patients With Multiple Sclerosis

CARLSBAD, Calif., June 11 /PRNewswire-FirstCall/ -- Orchestra Therapeutics, Inc. (Bulletin Board: OCHT) announced today positive new data from its completed Phase II open-label study of NeuroVax(TM), an investigational T Cell Receptor (TCR) peptide vaccine for the treatment of relapsing-remitting multiple sclerosis (MS). The new data, presented last week at the Federation of Clinical Immunology Societies (FOCIS) annual meeting, showed that monthly vaccinations over one year with NeuroVax(TM) markedly expanded the capacity of regulatory T cells (Tregs) to recognize TCRs expressed by potentially pathogenic T cells. New data were also presented that showed NeuroVax(TM) produced a significant increase in TCR-specific T cells in patients with MS, including increases in interleukin-10-secreting T cells (IL-10) and Foxp3+ Tregs.

“These new findings provide evidence to support the network hypothesis, in which internal cell-cell recognition of antigen receptors can be greatly expanded in regulatory T cells by activating the system with NeuroVax(TM). These vaccine induced responses may help control the autoimmune processes that are thought to be the main cause of the inflammatory phase of MS” said Arthur A. Vandenbark, M.D., Ph.D., Senior Research Career Scientist at the VA Medical Center, and Professor of Neurology and Molecular Microbiology and Immunology at Oregon Health & Science University in Portland, OR., and lead author on the study. “Increases in both IL-10-secreting T cells and the Foxp3+ Tregs suggest that NeuroVax(TM) can stimulate native thymus-derived Foxp3+ Tregs as well as induce peripheral Foxp3+ Tregs from CD4+CD25- T cells through an IL-10 controlled mechanism.”

“These new data suggest that induction of an expanding population of TCR-reactive, Foxp3+ Tregs by NeuroVax(TM) may be able to exert broad and potent immunomodulatory effects on pathogenic T cells,” said Dr. Joseph O’Neill, President and CEO of Orchestra Therapeutics, Inc. “The indication that this vaccine candidate increases both native and induced types of Foxp3+ Tregs against a broad population of pathogenic T cell families is also important as it provides further insight into the targeted mechanism of NeuroVax(TM). Orchestra Therapeutics is investigating how this TCR peptide vaccine technology, pioneered with NeuroVax(TM), could be leveraged to develop similar therapeutic vaccines for other autoimmune diseases such as rheumatoid arthritis (RA) and psoriasis.”

In MS, a specific subset of a patient’s own white blood cells, pathogenic T cells, attack myelin, a fatty tissue in the central nervous system, which surrounds and protects nerve fibers. This pathologic process creates multiple areas of inflammation that ultimately lead to scarring (sclerosis) and that interfere with normal transmission of nerve impulses. This nerve damage, in turn, leads to a variety of chronic and often debilitating neurological symptoms, ranging from serious movement and balance problems to vision impairment.

NeuroVax(TM), which is currently being tested in a double-blind, placebo-controlled 200-patient Phase II study, may represent a significant advance in the treatment of MS, which affects more than 2.5 million people worldwide, including more than 400,000 in the United States. NeuroVax(TM) has been shown to stimulate strong, disease-specific cell-mediated immunity in nearly all treated patients. NeuroVax(TM) appears to work in part by enhancing levels of Foxp3+ Tregs, which may help regulate expression of pathogenic T cells in MS patients. The three TCR peptides combined in NeuroVax(TM) correspond to one or more TCR gene families which are over expressed in 90% of MS patients. Previous clinical trials conducted by the Company and other independent researchers have associated diminished levels of Foxp3+ Treg responses with the pathogenesis and progression of MS. This same mechanism appears to be important in the pathogenesis of other autoimmune diseases such as RA and psoriasis.

About the Study

These new mechanistic clinical data are from a recently completed open- label study examining immunological and clinical parameters in 27 NeuroVax(TM) treatment-naïve and nine previously NeuroVax(TM) vaccinated subjects with various forms of MS. Study participants received monthly injections of NeuroVax(TM) over a one year period.

About OHSU

Oregon Health & Science University, located in Portland, OR., includes the schools of dentistry, medicine, nursing and science and engineering; OHSU Hospital and Doernbecher Children’s Hospital; numerous primary care and specialty clinics; multiple research institutes; and several outreach and community service units.

About Orchestra Therapeutics

Orchestra Therapeutics, Inc., formerly The Immune Response Corporation , is an immuno-pharmaceutical company focused on the discovery and development of novel treatments for autoimmune diseases. The Company’s lead immune-based therapeutic product candidate is NeuroVax(TM) for the treatment of MS. In addition to MS, the Company has proprietary technology and prior clinical experience for evaluation of TCR peptide-based immune therapies for RA and psoriasis.

The Company also has two HIV product candidates, Remune(R) and IR103. The 52-week data from the first large cohort of HIV clinical trial participants from a now-terminated Phase II clinical trial have already been gathered, and analysis of the data will be completed and disclosed in the second quarter of 2007. Based on this data, the Company will consider strategic alternatives for the HIV program.

The targeted strategy behind the Company’s immune-based therapies is reflected in the name Orchestra. Rather than disrupting the function of the entire immune system, these therapeutic vaccines are designed to elicit a very specific response -- akin to correcting one instrument in an orchestra that is out of tune -- to help control disease.

This news release contains forward-looking statements. Forward-looking statements are often signaled by forms of words such as should, could, will, might, plan, projection, forecast, expect, guidance, potential and developing. Actual results could vary materially from those expected due to a variety of risk factors, including whether the Company will continue as a going concern and successfully raise proceeds from financing activities sufficient to fund operations and clinical trials of NeuroVax(TM), Remune(R) or IR103, the uncertainty of successful completion of any such clinical trials, the fact that the Company has not succeeded in commercializing any drug, the risk that NeuroVax(TM), Remune(R) or IR103 might not prove to be effective as a therapeutic vaccine, whether future trials will be conducted and whether the results of such trials will coincide with the results of NeuroVax(TM), Remune(R) or IR103 in preclinical trials and/or earlier clinical trials and the unresolved status of the Company’s HIV program. A more extensive set of risks is set forth in Orchestra Therapeutics’ SEC filings including, but not limited to, its Annual Report on Form 10-K for the year ended December 31, 2006, and its subsequent Quarterly Report filed on Form 10-Q. The Company undertakes no obligation to update the results of these forward-looking statements to reflect events or circumstances after today or to reflect the occurrence of unanticipated events.

NeuroVax(TM) is a trademark of Orchestra Therapeutics, Inc. Remune(R) is a registered trademark of Orchestra Therapeutics, Inc.

MEDIA CONTACT: Rachel Kessler Chamberlain Communications Group (212) 389-9155 rkessler@chamberlainpr.com INVESTOR CONTACT: Robert Giordano ROI Associates (212) 495-0201 rgiordano@roiny.com COMPANY CONTACT: Michael K. Green, COO Orchestra Therapeutics, Inc. (760) 431-7080 info@orchestratherapeutics

Orchestra Therapeutics, Inc.

CONTACT: MEDIA, Rachel Kessler of Chamberlain Communications Group,+1-212-389-9155, rkessler@chamberlainpr.com, for Orchestra Therapeutics,Inc.; INVESTORS, Robert Giordano of ROI Associates, +1-212-495-0201,rgiordano@roiny.com, for Orchestra Therapeutics, Inc.; COMPANY, Michael K.Green, COO of Orchestra Therapeutics, Inc., +1-760-431-7080,info@orchestratherapeutics

MORE ON THIS TOPIC