Vijay B. SamantPresident and Chief Executive OfficerVijay B. SamantPresident and Chief Executive Officer

September 2005September 2005

Safe HarborSafe HarborThis 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 OverviewVical 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 EP Solid Tumors Phase 1

Allovectin-7® Melanoma Phase 3

CMV Vaccine

Independent Product PipelineIndependent Product Pipeline

Transplants Phase 2

CMV: The Vical AdvantageCMV: 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 NeedUnmet Medical Need CMV Disease Burden (U.S.)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 CMVDNA Vaccine for CMVClinical StatusClinical 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 TrialPhase 2 Proof of Concept TrialHCT Vaccine StrategyHCT Vaccine Strategy

HCT Donor

HCT Recipient

HCTTransplant

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 weeksand 12 weeks

-3 weeks (Week -3, -2, -1)

D

160 Subjects

IL-2 EPIL-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 2005

• 0.5 mg dose cohort fully enrolled

• Preliminary data in 2006

Allovectin-7Allovectin-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 rate @ > 24 wks.

• Potential partners have advanced to due diligence• Unlikely to pursue Phase 3 trial without a partner

Pets/Livestock

Partnered Product PipelinePartnered Product Pipeline

VEGF-2 Coronary 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

Phase 1

Phase 1

PreventionSARS Phase 1

HIV Treatment/Prevention Phase 1

I.D. Vaccines

Angiogenesis

Veterinary

NIH

Merck

NIH

NIH

NIH

Corautus

Centelion

Merial

Aqua Health

CAD / PADHGF Phase 1 / Phase 3AnGes MG

AnGes MGAnGes 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 ProgramsOther 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 CollaborationsNIH Collaborations

• NIH vaccine development programs• HIV

• Ebola

• West Nile virus

• SARS

• NIH grants• CMV

• Anthrax

• HSV

• Influenza

Supply of clinical materialAccess to IPFully-funded clinical trials

DNA Vaccine for HIVDNA Vaccine for HIV

• Six-plasmid construct• Includes genes for envelope and internal proteins

• Includes genes for three clades

• Phase 1 complete• Data expected 2005-2006

• $12 million in new production orders• Supplies for large Phase 2 study

DNA Vaccine for EbolaDNA 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 WNVDNA 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 GrantsNIH GrantsVaccine Status Funding

• Anthrax Phase 1 $7 million• CMV Phase 2 $4 million• Avian influenza Preclinical $3 million• Influenza Preclinical <$1 million• HSV Preclinical <$1 million

Merck PartnershipMerck 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 ProgramsAnimal 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

RevenuesRevenues

Financial HighlightsFinancial Highlights(in millions except per share amounts) Q205 Q204 Revenues $ 4.8 $ 5.7Expenses 10.0 11.2Net investment income 0.2 0.1Net loss $ (5.0) $ (5.3)

Net loss per share $ (0.21) $ (0.23)

Forecast 2005 net loss $ (23 – 26)

Cash, cash equivalents and marketable securities @ 6/30 $ 59 Shares outstanding @ 6/30 23.5

MilestonesMilestonesAllovectin-7® Special Protocol AssessmentNIH Phase 1 trial with West Nile virus vaccineNew angiogenesis collaboration with AnGes MGMerck exercise of cancer vaccine options$12.1 million in production orders from NIH for HIV vaccineAqua Health vaccine approved in CanadaStarted IL-2 / electroporation Phase 1 trialMerck expanded cancer vaccine optionsCRADA 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 PrioritiesProgram Priorities

• Allovectin – partnering

• CMV Phase 2

• IL-2 EP Phase 1

• HIV EP – NIH

• Influenza – NIH

• Technology out-licensing