The Immune Response Corporation Presents the First Human Data with IR103 at the International AIDS Society Meeting in Rio; REMUNE(R) Data Also Presented in Drug-Naive HIV Positive Individuals

The Immune Response Corporation (Nasdaq:IMNR), abiopharmaceutical company dedicated to becoming a leading immune-basedtherapy company in HIV and multiple sclerosis (MS), announced that thefirst clinical trial data with IR103, the Company's newestimmune-based therapy candidate, were presented as a late-breaker attoday's sessions at the International AIDS Society (IAS) meeting inRio de Janeiro, Brazil. In addition, an oral and poster presentationof data from a Phase II study conducted in Italy with REMUNE(R), theCompany's lead HIV product candidate, was presented.

Preliminary results of the IR103 trial indicate the product issafe, induces HIV-specific immune responses and greatly enhancesIFN-gamma and RANTES mRNA. IFN-gamma and RANTES are considered immunesystem markers that give an estimate of the robustness of the immuneresponse generated by IR103 in patients. The REMUNE(R) data from theItalian trial were obtained in drug-naive HIV positive patients whichis the same group the Company plans to examine in registration trialsnext year.

"We are encouraged that these early results from the first IR103human trial confirm results previously obtained in animal studies,demonstrating enhancement of HIV-specific immune responses," said JohnN. Bonfiglio, Ph.D., President and Chief Executive Officer of TheImmune Response Corporation. "The REMUNE(R) results presented todayare another example of the advancement of that program and have beenhelpful as we design our Phase III registration trials for next year."

"This is the first time we are presenting data from our firstIR103 human trial and we are excited to be able to do so at thisprestigious forum," said Georgia Theofan, Ph.D., Vice President ofClinical Development at The Immune Response Corporation. "We feelespecially proud that these results were selected to be a late-breakerat this important meeting."

Early safety data from 43 patients and preliminary immunology datafrom 14 patients in this ongoing clinical trial were included in thepreliminary results presented today at IAS. IR103 was well toleratedand no related serious or grade IV adverse events were reported.Median changes from baseline at week 24 in IFN-gamma and RANTES mRNAdemonstrated enhanced responses in the patient receiving thecombination of REMUNE(R) and Amplivax(TM) at all doses. The effects ofthe combination were dose dependent with the maximum effect seen inpatients treated with REMUNE(R) plus 1.0 mg of Amplivax(TM). PlasmaIL-7 levels were also increased, but only in patients receiving thehighest dose of Amplivax(TM).

About the IR103 Study

The current phase of the study presented today, which is stillongoing, is a 45-patient, five-arm, randomized, single-blind,controlled, multi-center Phase I/II study that commenced enrollment in2004 and will run for approximately 28 weeks after the last patient isenrolled. The primary objective of this study is to evaluate safetyand bioactivity, or the ability to generate HIV-specific immuneresponses, to various doses of IR103, a therapeutic HIV vaccineconsisting of a whole-killed HIV-1 antigen combined with animmunostimulatory oligonucleotide adjuvant (Amplivax(TM)), in HIVpatients on HAART (highly active antiretroviral therapy). Evaluationof IR103 in antiretroviral-naive patients is also in progress. Abilityto generate HIV-1 specific immune responses is thought to be animportant indicator of clinical utility.

Amplivax(TM) was developed by Hybridon, Inc. and has been licensedto The Immune Response Corporation.

About the Italian Study

The multi-center, single-blind, randomized study followed 51patients over 28 weeks following treatment with REMUNE(R), IFA orsaline. Patients were antiretroviral naive and had HIV RNA levelsbetween 10,000 and 40,000 copies/mL and CD4+ counts between 400 and800 cells/microliter at study entry. Patients received threeinjections of REMUNE(R) (n=19), IFA (n=10), or saline (n=11) at weeks0, 12, and 24. A fourth group received only a single injection ofREMUNE(R) at week 0 (n = 11). Topline data from this study wasincluded in a press release earlier this year.

The final analysis included data from 51 patients enrolled in thestudy, and showed that median absolute CD4+ cell counts remainedstable through week 28 in the patients that received 3 injections ofREMUNE(R), but declined in both the IFA and saline groups. REMUNE(R)'seffect on immune reconstitution as further evidenced by an augmentedserum concentration of IL-7 and increases in naive CD4+ T-cellssuggests a possible mode of action via stimulation of thymus function.The researchers believe that this effect on the thymus may beimportant in boosting the body's own defense against HIV. Furtherresearch is being carried out to confirm this positive effect onthymus and the circulating lymphocytes phenotypes.

Both trials were intended to explore the potential utility ofREMUNE(R) and IR103, and neither trial was designed to have enoughstatistical power to be used for regulatory approval. The Company isplanning a clinical program that would use the data from these twotrials to design registration trials in the near future. REMUNE(R) isin Phase II development by The Immune Response Corporation and is notapproved by any regulatory agencies in any country at this time.

About The Immune Response Corporation

The Immune Response Corporation (Nasdaq:IMNR) is abiopharmaceutical company dedicated to becoming a leading immune-basedtherapy company in HIV and MS. The Company's HIV products are based onits patented whole-killed virus technology, co-invented by Companyfounder Dr. Jonas Salk to stimulate HIV immune responses. REMUNE(R),currently in Phase II clinical trials, is being developed as afirst-line treatment for people with early-stage HIV. We haveinitiated development of a new immune-based therapy, IR103, whichincorporates a second-generation immunostimulatory oligonucleotideadjuvant and is currently in Phase I/II clinical trials in Canada andthe United Kingdom.

The Immune Response Corporation is also developing an immune-basedtherapy for MS, NeuroVax(TM), which is currently in Phase II clinicaltrials and has shown potential therapeutic value for thisdifficult-to-treat disease.

Please visit The Immune Response Corporation at www.imnr.com.

This news release contains forward-looking statements.Forward-looking statements are often signaled by forms of words suchas should, could, will, might, plan, projection, forecast, expect,guidance, potential and developing. Actual results could varymaterially from those expected due to a variety of risk factors,including whether the Company will continue as a going concern andsuccessfully raise proceeds from financing activities sufficient tofund operations and additional clinical trials of REMUNE(R),NeuroVax(TM) or IR103, the uncertainty of successful completion of anysuch clinical trials, the fact that the Company has not succeeded incommercializing any drug, the risk that REMUNE(R), NeuroVax(TM) orIR103 might not prove to be effective as either a therapeutic orpreventive vaccine, whether future trials will be conducted andwhether the results of such trials will coincide with the results ofREMUNE(R), NeuroVax(TM) or IR103 in preclinical trials and/or earlierclinical trials. These risks, among others, are set forth in TheImmune Response Corporation's SEC filings including, but not limitedto, its Annual Report on Form 10-K for the year ended December 31,2004 and its subsequent Quarterly Reports filed on Form 10-Q. TheCompany undertakes no obligation to update the results of theseforward-looking statements to reflect events or circumstances aftertoday or to reflect the occurrence of unanticipated events.

REMUNE(R) is a registered trademark of The Immune ResponseCorporation. NeuroVax(TM) is a trademark of The Immune ResponseCorporation. Amplivax(TM) is a trademark of Hybridon, Inc.