Epimmune Scientists Report Positive Pre-Clinical Data on Vaccine Designed To Combat HIV's Ability to Mutate

Company on Track to Initiate Clinical Trials Late This Year or Early 2002

Of Epitope-Based Vaccine for the Prevention and Treatment of HIV



Apr 02, 2001, 01:00 ET from Epimmune Inc.

    KEYSTONE, Colo., April 2 /PRNewswire/ -- Epimmune Inc. (Nasdaq: EPMN)
 today announced positive pre-clinical data on its HIV vaccine that is designed
 to directly address the problem of viral mutation.  At the Keystone Symposium:
 "AIDS Vaccines in the New Millennium" on March 30, 2001 in Keystone, Colorado,
 Company scientists reported that the vaccine stimulated multiple anti-HIV
 cytotoxic T-cell immune responses in animal models.  Epimmune has begun
 manufacturing the vaccine for human testing and plans to initiate clinical
 trials late this year or early 2002 in both non-infected volunteers and in
 individuals infected with HIV.
     The current standard HIV therapy for Americans is a three-drug
 anti-retroviral combination that costs approximately $15,000 per year.  While
 anti-retroviral drugs are effective at suppressing HIV replication in infected
 individuals, they do not eliminate the infection and have toxic side effects
 that impede their long-term use.  A vaccine that can provide both preventative
 and therapeutic benefits has great potential to help control the AIDS epidemic
 and curtail the costs and side effects of anti-retroviral therapies.
     "A major challenge to the development of an effective AIDS vaccine is the
 ability of HIV to mutate.  Epimmune's vaccine is designed to directly address
 this problem," said Mark Newman, Ph.D., Vice President of the Infectious
 Disease Program at Epimmune.  "One of the unique features of Epimmune's
 vaccine is that it is composed of epitopes, or protein fragments, which are
 strategically selected from non-mutating regions of HIV.  As a result, it is
 expected to be harder for the virus to develop variants that can escape the
 vaccine-induced immune response."
     Strong cellular immunity is characteristic of long-term non-progressors or
 HIV-positive individuals who do not progress to AIDS for long periods even
 without anti-retroviral drug therapy.  Epimmune's approach to vaccine
 development is based on epitopes from non-mutating regions of multiple virus
 proteins that are specifically selected for their ability to stimulate two
 types of cellular immunity, cytotoxic T-cells (CTLs) and helper T-cells
 (HTLs).  Together, CTLs and HTLs comprise the body's natural defense against
 HIV in which CTLs are capable of directly destroying virus-infected cells but
 require HTLs, which produce immune-boosting chemicals, for proper functioning.
     Epimmune has designed its vaccine to provide immunity against many HIV
 clades (HIV strains that are common to a certain geographical region),
 including those that are prevalent in the United States, Europe, Africa and
 India.  The vaccine is also designed to provide broad population coverage
 regardless of ethnicity.
     Epimmune's vaccine will be delivered as DNA in combination with PVP, a
 polymer gene delivery technology licensed from Valentis, Inc.  The PVP polymer
 has been shown to increase the efficiency of vaccine uptake by immune cells
 and enhance potency in animal studies.  Epimmune has also linked its HIV
 vaccine with its proprietary PADRE(TM) universal helper T-cell epitope.  PADRE
 is an HTL booster which, when combined with CTL epitopes, enhances the
 magnitude and duration of the immune response.  Finally, the vaccine construct
 has also been optimized to ensure that the epitopes are processed efficiently
 and correctly once inside the cell.  The epitopes are placed in a specific
 order (like beads on a string) that allows cellular enzymes to recognize the
 appropriate places to liberate the epitopes from the chain, thus improving the
 efficiency and potency of the vaccine.
     In August 2000, Epimmune was awarded a National Institutes of Health (NIH)
 grant from the Integrated Pre-clinical/Clinical Program (IPCP) of the National
 Institute of Allergy and Infectious Disease (NIAID), Division of AIDS, to
 advance epitope-based vaccines into clinical trials.  The grant funds a
 four-year program designed to evaluate Epimmune's epitope-based vaccines as a
 therapeutic strategy for the treatment of HIV-1 infected individuals on highly
 active anti-retroviral therapy (HAART).  The program is closely associated
 with the NIAID clinical trials network and represents a collaborative effort
 between Epimmune and academic investigators from the University of Colorado
 Health Services Center and the University of Wisconsin Regional Primate
 Center.
 
     Epimmune Inc. is a leader in using gene maps of cancer-associated proteins
 and infectious agents to design vaccines that induce cellular immunity.  The
 Company's extensive technology platform is based on its pioneering work in
 deciphering the genetic code which regulates T-cell activation and identifying
 antigen fragments known as epitopes which can activate highly targeted T-cell
 responses to tumors, viruses, bacteria and parasites.  This new field of
 pharmacology opens two significant areas of pharmaceutical development:
 protective vaccines that activate T-cell protection against infections, such
 as HIV and hepatitis C, and therapeutic vaccines designed to stimulate
 antigen-specific T-cell responses to infections, such as HIV, hepatitis C and
 hepatitis B, and tumors such as breast, colon, lung and prostate.  For more
 information on Epimmune, visit www.epimmune.com.
 
     This press release includes forward-looking statements that reflect
 management's current views of future events, including the utility of the
 Company's technology, the anticipated benefits of HIV vaccine being developed
 by the Company and the timing for commencement of clinical trials of the HIV
 vaccine.  Actual results may differ materially from the above forward-looking
 statements due to a number of important factors, including but not limited to
 the risks associated with the Company's ability to develop vaccines using
 epitopes, the ability of epitope-based vaccines to control HIV, the safety and
 efficacy of epitope-based vaccines in humans, the Company's ability to enter
 into and maintain new collaborations, achievement of research and development
 objectives by the Company and any collaborator, the timing and cost of
 conducting human clinical trials, the regulatory approval process, and the
 possibility that testing may reveal undesirable and unintended side effects or
 other characteristics that may prevent or limit the commercial use of proposed
 products.  These factors are more fully discussed in the Company's 2000 Form
 10-K, the most recent 10-Qs and other periodic reports filed with the
 Securities and Exchange Commission.
 
     For further information please contact Robert DeVaere, VP, Finance, CFO of
 Epimmune Inc., 858-860-2500; or media, Laura Hansen of Susan E. Atkins &
 Associates, 858-860-0266, for Epimmune Inc.
 
 

SOURCE Epimmune Inc.
    KEYSTONE, Colo., April 2 /PRNewswire/ -- Epimmune Inc. (Nasdaq: EPMN)
 today announced positive pre-clinical data on its HIV vaccine that is designed
 to directly address the problem of viral mutation.  At the Keystone Symposium:
 "AIDS Vaccines in the New Millennium" on March 30, 2001 in Keystone, Colorado,
 Company scientists reported that the vaccine stimulated multiple anti-HIV
 cytotoxic T-cell immune responses in animal models.  Epimmune has begun
 manufacturing the vaccine for human testing and plans to initiate clinical
 trials late this year or early 2002 in both non-infected volunteers and in
 individuals infected with HIV.
     The current standard HIV therapy for Americans is a three-drug
 anti-retroviral combination that costs approximately $15,000 per year.  While
 anti-retroviral drugs are effective at suppressing HIV replication in infected
 individuals, they do not eliminate the infection and have toxic side effects
 that impede their long-term use.  A vaccine that can provide both preventative
 and therapeutic benefits has great potential to help control the AIDS epidemic
 and curtail the costs and side effects of anti-retroviral therapies.
     "A major challenge to the development of an effective AIDS vaccine is the
 ability of HIV to mutate.  Epimmune's vaccine is designed to directly address
 this problem," said Mark Newman, Ph.D., Vice President of the Infectious
 Disease Program at Epimmune.  "One of the unique features of Epimmune's
 vaccine is that it is composed of epitopes, or protein fragments, which are
 strategically selected from non-mutating regions of HIV.  As a result, it is
 expected to be harder for the virus to develop variants that can escape the
 vaccine-induced immune response."
     Strong cellular immunity is characteristic of long-term non-progressors or
 HIV-positive individuals who do not progress to AIDS for long periods even
 without anti-retroviral drug therapy.  Epimmune's approach to vaccine
 development is based on epitopes from non-mutating regions of multiple virus
 proteins that are specifically selected for their ability to stimulate two
 types of cellular immunity, cytotoxic T-cells (CTLs) and helper T-cells
 (HTLs).  Together, CTLs and HTLs comprise the body's natural defense against
 HIV in which CTLs are capable of directly destroying virus-infected cells but
 require HTLs, which produce immune-boosting chemicals, for proper functioning.
     Epimmune has designed its vaccine to provide immunity against many HIV
 clades (HIV strains that are common to a certain geographical region),
 including those that are prevalent in the United States, Europe, Africa and
 India.  The vaccine is also designed to provide broad population coverage
 regardless of ethnicity.
     Epimmune's vaccine will be delivered as DNA in combination with PVP, a
 polymer gene delivery technology licensed from Valentis, Inc.  The PVP polymer
 has been shown to increase the efficiency of vaccine uptake by immune cells
 and enhance potency in animal studies.  Epimmune has also linked its HIV
 vaccine with its proprietary PADRE(TM) universal helper T-cell epitope.  PADRE
 is an HTL booster which, when combined with CTL epitopes, enhances the
 magnitude and duration of the immune response.  Finally, the vaccine construct
 has also been optimized to ensure that the epitopes are processed efficiently
 and correctly once inside the cell.  The epitopes are placed in a specific
 order (like beads on a string) that allows cellular enzymes to recognize the
 appropriate places to liberate the epitopes from the chain, thus improving the
 efficiency and potency of the vaccine.
     In August 2000, Epimmune was awarded a National Institutes of Health (NIH)
 grant from the Integrated Pre-clinical/Clinical Program (IPCP) of the National
 Institute of Allergy and Infectious Disease (NIAID), Division of AIDS, to
 advance epitope-based vaccines into clinical trials.  The grant funds a
 four-year program designed to evaluate Epimmune's epitope-based vaccines as a
 therapeutic strategy for the treatment of HIV-1 infected individuals on highly
 active anti-retroviral therapy (HAART).  The program is closely associated
 with the NIAID clinical trials network and represents a collaborative effort
 between Epimmune and academic investigators from the University of Colorado
 Health Services Center and the University of Wisconsin Regional Primate
 Center.
 
     Epimmune Inc. is a leader in using gene maps of cancer-associated proteins
 and infectious agents to design vaccines that induce cellular immunity.  The
 Company's extensive technology platform is based on its pioneering work in
 deciphering the genetic code which regulates T-cell activation and identifying
 antigen fragments known as epitopes which can activate highly targeted T-cell
 responses to tumors, viruses, bacteria and parasites.  This new field of
 pharmacology opens two significant areas of pharmaceutical development:
 protective vaccines that activate T-cell protection against infections, such
 as HIV and hepatitis C, and therapeutic vaccines designed to stimulate
 antigen-specific T-cell responses to infections, such as HIV, hepatitis C and
 hepatitis B, and tumors such as breast, colon, lung and prostate.  For more
 information on Epimmune, visit www.epimmune.com.
 
     This press release includes forward-looking statements that reflect
 management's current views of future events, including the utility of the
 Company's technology, the anticipated benefits of HIV vaccine being developed
 by the Company and the timing for commencement of clinical trials of the HIV
 vaccine.  Actual results may differ materially from the above forward-looking
 statements due to a number of important factors, including but not limited to
 the risks associated with the Company's ability to develop vaccines using
 epitopes, the ability of epitope-based vaccines to control HIV, the safety and
 efficacy of epitope-based vaccines in humans, the Company's ability to enter
 into and maintain new collaborations, achievement of research and development
 objectives by the Company and any collaborator, the timing and cost of
 conducting human clinical trials, the regulatory approval process, and the
 possibility that testing may reveal undesirable and unintended side effects or
 other characteristics that may prevent or limit the commercial use of proposed
 products.  These factors are more fully discussed in the Company's 2000 Form
 10-K, the most recent 10-Qs and other periodic reports filed with the
 Securities and Exchange Commission.
 
     For further information please contact Robert DeVaere, VP, Finance, CFO of
 Epimmune Inc., 858-860-2500; or media, Laura Hansen of Susan E. Atkins &
 Associates, 858-860-0266, for Epimmune Inc.
 
 SOURCE  Epimmune Inc.