Vijay B. Samant President and Chief Executive Officer September 2005

Safe Harbor This presentation contains forward-looking statements that are subject to risks and uncertainties that could cause actual results to differ materially from those set forth in the forward- looking statements, including whether any product candidates will be shown to be safe and efficacious in clinical trials and the risks set forth in the company’s filings with the Securities and Exchange Commission. Actual results may differ materially from those projected. These forward-looking statements represent the company’s judgment as of the date of this presentation. The company disclaims, however, any intent or obligation to update these forward-looking statements.

Vical Overview Platform technology Non-viral gene delivery  13 active dev. programs Broad applications Vaccines Cancer Angiogenesis Animal health Key partnerships with pharma partners Broad collaboration with NIH Experienced management team

IL-2 EPSolid TumorsPhase 1 Allovectin-7 ® Melanoma  Phase 3 CMV Vaccine Independent Product Pipeline Transplants  Phase 2

CMV: The Vical Advantage The opportunity Herpes virus – infects 50-85% in the US by age 40 No vaccine available Initial vaccine target: transplant patients Potential follow-on target: at-risk women Advantages of Vical’s vaccine approach Ability to harness antibody and T-cell responses Non-infective - a MUST for immunosuppressed patients Proof of efficacy in transplant patients Small clinical trials

Unmet Medical Need CMV Disease Burden (U.S.) Transplant recipients Incidence: 2,800 patients/yr Serious effects: 1,600 patients/yr Mortality: 160 deaths/yr Congenital infections Incidence: 40,000 infants/yr Neurological effects: 9,400/yr Mortality: 400 deaths/yr Total U.S. healthcare burden: $4 billion/yr

DNA Vaccine for CMV Clinical Status Encouraging Phase 1 data presented in April 2005 Safe and well-tolerated Immunogenic Antibody responses T-cell responses Advancing to Phase 2 in 2005 $4.1 million in NIH grants

Phase 2 Proof of Concept Trial HCT Vaccine Strategy HCT Donor HCT Recipient HCT Transplant I. Donor receives 3 injections prior to donation R II. Recipient receives 1 injection prior to transplant and 2 injections after transplant Day -3 to -5, +3-6 weeks and 12 weeks -3 weeks (Week -3, -2, -1) D 160 Subjects

IL-2 EP Objective Sustained local expression of IL-2 at therapeutic levels Avoid systemic toxicity associated with protein therapy Phase 1 Trial Design Up to 29 patients Dose escalation: 0.5, 1.5, 5.0 mg Highest dose cohort expanded to 20 patients total Status Trial started July mg dose cohort fully enrolled Preliminary data in 2006

Allovectin-7 ® Phase 2 high-dose trial complete Excellent safety profile 11.8% objective response rate (15 pts of 127 pts) Special Protocol Assessment complete 375 chemo-naïve patients randomized 2:1 Primary endpoint: objective response > 24 wks. Potential partners have advanced to due diligence Unlikely to pursue Phase 3 trial without a partner

Pets/Livestock Partnered Product Pipeline VEGF-2Coronary Artery Disease (CAD) FGF-1 I.D./Cancer Peripheral Artery Disease (PAD) Phase 2 Phase 2B SalmonI.D. Approved Research  Field Trials Ebola HIV WNV Treatment/Prevention Humans Biodefense Phase 1 PreventionSARS Phase 1 HIVTreatment/Prevention Phase 1 I.D. Vaccines Angiogenesis Veterinary NIH Merck NIH Corautus Centelion Merial Aqua Health CAD / PADHGF Phase 1 / Phase 3 AnGes MG

Japanese company founded December 1999 Hepatocyte Growth Factor technology from Osaka U. License from Vical May 2005 $1 million + milestones and royalties Phase 3 PAD started 2004 – Japan Phase 2 PAD started 2003 – USA Phase 1 CAD started 2004 – USA

Other Angiogenesis Programs Sanofi Phase 2 PAD started 2002 – USA and Europe Phase 2 PAD started 2004 – USA and Europe $10+ million received (under multiple agreements) Corautus Genetics Phase 2b CAD started 2004 – USA

NIH Collaborations NIH vaccine development programs HIV Ebola West Nile virus SARS NIH grants CMV Anthrax HSV Influenza  Supply of clinical material  Access to IP  Fully-funded clinical trials

DNA Vaccine for HIV Six-plasmid construct Includes genes for envelope and internal proteins Includes genes for three clades Phase 1 complete Data expected $12 million in new production orders Supplies for large Phase 2 study

DNA Vaccine for Ebola Phase 1 started November 2003 First time in man with Ebola vaccine Enrollment in Phase 1 complete – 27 volunteers Immunogenicity data 2005 Approval under FDA’s Animal Rule Commercialization rights from NIH Project BioShield $350 million allocated for Ebola

DNA Vaccine for WNV Highly immunogenic Neutralizing antibodies Premembrane (prM) Envelope (E) Protection in mice and horses Phase 1 started April 2005 Commercialization rights from CDC and NIH

NIH Grants VaccineStatusFunding AnthraxPhase 1$7 million CMV  Phase 2$4 million Avian influenzaPreclinical$3 million InfluenzaPreclinical<$1 million HSVPreclinical<$1 million

Merck Partnership HIV, hep C, hep B, cancer 6/05 – exercised options on 3 cancer targets 9/05 – took additional cancer vaccine options Commercial terms $28 million received Additional milestones and royalties Co-promotion rights in U.S.

Animal Health Programs Merial (Merck / Sanofi) Animal health vaccines for I.D. and cancer Conditional approval for canine melanoma vaccine Expected early 2006 $7+ million received Aqua Health (Novartis) DNA vaccine against IHNV in salmon Licensed in Canada July 2005 Commercially marketed

Revenues

Financial Highlights (in millions except per share amounts) Q205Q204 Revenues$4.8$5.7 Expenses Net investment income Net loss$(5.0)$(5.3) Net loss per share$(0.21)$(0.23) Forecast 2005 net loss$ (23 – 26) Cash, cash equivalents and marketable 6/30 $59 Shares 6/3023.5

Milestones Allovectin-7 ® Special Protocol Assessment NIH Phase 1 trial with West Nile virus vaccine New angiogenesis collaboration with AnGes MG Merck exercise of cancer vaccine options $12.1 million in production orders from NIH for HIV vaccine Aqua Health vaccine approved in Canada Started IL-2 / electroporation Phase 1 trial Merck expanded cancer vaccine options CRADA with NIH for HIV-EP program $3 million NIH grant for human vaccine against pandemic avian flu Allovectin-7 ® partnership update Start Phase 2 CMV vaccine trial in transplant patients Partner updates on angiogenesis trials NIH update on HIV and Ebola trials Approval of Merial melanoma vaccine for dogs

Program Priorities Allovectin – partnering CMV Phase 2 IL-2 EP Phase 1 HIV EP – NIH Influenza – NIH Technology out-licensing