1

| 1

Dengue: About the Disease and Emerging Vaccines

Gustavo Dayan, MD

Vaccine Preventable Diseases: Policy, Practices, Preparedness

New York City, NY

July 23, 2012

| 2

Overview

● Dengue

● Virus

● Disease

● Public health burden

● Vaccines in development

● Live virus

● Inactivated

● Subunit

● DNA/vector

● Sanofi Pasteur dengue vaccine

● Clinical development

● Safety

● Immunogenicity

| 3

•Flavivirus (YF, JE, TBE, WN)

•Positive sense single stranded RNA (~11kb) that

codes for 3 structural proteins & 7 non-structural

proteins

• Four closely related, but

antigenically distinct serotypes (DEN 1-4)

- Immunity: serotype specific and prolonged - Cross protection: little and short duration - Some variants more virulent and with greater epidemic potential

Prot é ines de structure 5 ’ Non

Codant 3 ’ Non

Codant

Prot é ines non stucturales NS Prot é ines de structure 5 ’ Non

Codant 3 ’ Non

Codant

Prot é ines non stucturales NS

NS3 C E NS1 NS2A NS2B NS4A NS4B NS5

Structural

Proteins

5’ NC 3 ’ NC

prM

Non Structural Proteins Zhang et al., 2003,

Dengue Virus

Source: Zhang Structure of Dengue Virus Cell, 2002;(108):717–725.

| 4

Dengue – Clinical Stages

● Asymptomatic Dengue Virus Infection

● Non-specific Febrile Illness

● Dengue Fever (DF) ● High fever for 5-7 days, with headache,

myalgia

● Usually followed by 2-3 weeks of debilitating fatigue

● Dengue Hemorrhagic Fever (DHF) ● DF with vascular permeability,

● Primarily in children, with a peak around 5-9 years old

● In outbreak situations, DHF is seen in all ages

● Case fatality rate

• 20% without treatment

• <1% with treatment

● Dengue Shock Syndrome (DSS)

DSS

DHF

Dengue Fever

Undifferentiated Fever

Asymptomatic

| 5

Courtesy Dr. S. Kalayanarooj

Adolescent diagnosed with dengue fever. Dengue Unit

Ratchaburi Hospital, Thailand – Feb 2011

| 6

Dengue – Public Health Burden

● Mosquito borne disease

● Aedes aegypti main vector

● Arthropod-borne viral disease with highest morbidity

and mortality

● 2.5 billion people at risk in over 100 countries

● >50 million people infected annually

● 2 million, mostly children, develop a severe form of the

disease

Source:

CDC - Outbreak Notice - Update: Dengue in Tropical and Subtropical Regions available on: http://wwwnc.cdc.gov/travel/notices/outbreak-notice/dengue-tropical-sub-tropical.htm

WHO - Dengue and dengue haemorrhagic fever, Fact sheet n

117, March 2009, available on: http://www.who.int/mediacentre/factsheets/fs117/en

2

| 7

Global Dengue Risk

Source: Simmons CP, et al. N Engl J Med. 2012;366-1423-32

| 8

Dengue in the Americas, 1980-2010

0

200,000

400,000

600,000

800,000

1,000,000

1,200,000

1,400,000

1,600,000

1,800,000

19

80

19

82

19

84

19

86

19

88

19

90

19

92

19

94

19

96

19

98

20

00

20

02

20

04

20

06

20

08

20

10

Y E AR

NU

MB

ER

OF

CA

SE

S

YEAR 1981 CUBA 344,203

YEAR 2002 HONDURAS 32.269 COLOMBIA 76,996 VENEZUELA 37,676 BRAZIL 780,644

YEAR 2009 ARGENTINA 26,612 BOLIVIA 84,047 MEXICO 249,763 COLOMBIA 51,543 VENEZUELA 65,869 BRAZIL 528,883

YEAR 2010 COLOMBIA 157,152 VENEZUELA 123,967 BRAZIL 1,004,392 HONDURAS 66,814 GUADELOUPE 41,100 PUERTO RICO 21,298

YEAR 1998 MEXICO 23,639 COLOMBIA 63,182 VENEZUELA 37,586 BRAZIL 535,388

Source:

Pan American Health Organization (PAHO). Number of reported cases of dengue & dengue haemorrhagic fever (DHF), Region of the Americas

Available at URL: http://new.paho.org/hq/index.php?option=com_content&task=view&id=264&Itemid=363&lang=en

| 9

Dengue Incidence in the Americas, 1980-2010

| 10

Dengue - Public Health Challenge

● WHO Neglected Tropical Diseases Group (WHA,

Geneva - May 2012)

● Targets and milestones for control of neglected tropical

diseases, 2015-2020

● To reduce dengue deaths by 50% by 2020

● To reduce dengue morbidity by at least 25% by 2020

Source: Accelerating Work to Overcome the Global Impact of Neglected Tropical Diseases - a roadmap for Implementation (WHO, May 2012)

| 11

Dengue Prevention

● Prevention relies on vector control and personal protection measures ● Difficult to enforce and maintain, expensive

● Development of a dengue vaccine is viewed as a public health priority

| 12

Virus isolation(Hotta & Kimura)

Sabin & Schelsinger2

19441943 19561944-45 1970 -’80

W. Hammon3

Sabin, Schelsinger2

US Army/Univ. Hawaii

/Univ MahidolThailand

/Fund. Rockefeller4

Attenuation

of DEN viruses

LAV DEN1-4(1st generation)

1928-1930

Blanc &

Caminopetros1

Killed & Attenuated

DEN vaccines

Construction

of chimeric

DEN4/DEN2

(2nd generation)

1990 - 2000

Bray M. et al

19915

Construction

of chimeric

YF/DEN2

Guirakhoo et al

20006 Construction

of chimeric

YF/DEN1,3,4

Guirakhoo et al

20017

Virus isolation and identification of serotypes

Dengue Vaccines

BZ 2009

1: AJTMH 1931;77:77-102 2: Science 1945;101(2634):640-642 3: Science 1960;131:1102-3 4: AJTMH 2003;69(Suppl 6):5-11

5: J Virol 1996;70:4162-6 6: J Virol 2000;74:3020-8 7: J Virol 2001;75:7290-7304

DEN3&4

ManilaDEN1 Hawaii

DEN N. Guinea

Monovalent

LAV DEN1

Killed DEN

vaccines

Simmons et al1

Virus isolation(Hotta & Kimura)

Sabin & Schelsinger2

19441943 19561944-45 1970 -’80

W. Hammon3

Sabin, Schelsinger2

US Army/Univ. Hawaii

/Univ MahidolThailand

/Fund. Rockefeller4

Attenuation

of DEN viruses

LAV DEN1-4(1st generation)

1928-1930

Blanc &

Caminopetros1

Killed & Attenuated

DEN vaccines

Construction

of chimeric

DEN4/DEN2

(2nd generation)

1990 - 2000

Bray M. et al

19915

Construction

of chimeric

YF/DEN2

Guirakhoo et al

20006 Construction

of chimeric

YF/DEN1,3,4

Guirakhoo et al

20017

Virus isolation and identification of serotypes

Dengue Vaccines

BZ 2009

1: AJTMH 1931;77:77-102 2: Science 1945;101(2634):640-642 3: Science 1960;131:1102-3 4: AJTMH 2003;69(Suppl 6):5-11

5: J Virol 1996;70:4162-6 6: J Virol 2000;74:3020-8 7: J Virol 2001;75:7290-7304

DEN3&4

ManilaDEN1 Hawaii

DEN N. Guinea

Monovalent

LAV DEN1

Killed DEN

vaccines

Simmons et al1

History of Dengue Vaccines

3

| 13

Challenges for Dengue Vaccine Development

● 4 different serotypes

● Technical difficulties

● Inter-serotype competition

● Need for balanced protection against all four serotypes

● There is no animal model for the disease

● Theoretical risk of immunoenhancement after sequential infections (antibody-dependent enhancement - ADE): need for a combined tetravalent vaccine

● No established correlates of protection – efficacy trials are needed

| 14

Dengue Vaccines in Development

● Live virus vaccines

Traditional attenuation

Recombinant

● Inactivated vaccines

● Subunit vaccines

● DNA vaccines

● Vector vaccines

| 15

Candidate Vaccines I -- Live Virus Vaccines

● Traditional attenuation

● Cell culture passages

• PDK, PRhL cells - WRAIR/GSK

Sun et al Hum Vaccin. 2009;5(1):33-40

● Recombinant ● Molecular attenuation through selective mutations and chimerization

• E.g., rDENV4- Δ30 - NIH/ University of Maryland

• Blaney et al Curr Top Microbiol Immunol 2010;338:145-58

● Insertion of dengue structural genes (prM/E) in a traditionally attenuated dengue virus

• DENV2 16681 PDK-53 vaccine strain - CDC/Inviragen

• Huang et al. J Virol 2003;77(21):11436-47

● Insertion of dengue structural genes (prM/E) in the yellow fever vaccine virus

• Yellow fever vaccine virus strain YF17D - Acambis/Sanofi Pasteur Capeding et al Vaccine 2011;29(22):3863-72

| 16

Candidate Vaccines II

● Inactivated vaccines - WRAIR/GSK Putnak et al. Vaccine 2005;23:4442-52

● Subunit vaccines

● Envelope + NS1 Ag- Hawaii Biotech/Merck Clements et al. Vaccine 2010;28(15):2705-15

● Protein DEN E Structural Subunits – Genetic and Biotecnology Center Cuba

Valdes et al. Clin Vaccine Immunol. 2011;18(3):455-9

● DNA and vector vaccines ● DNA – NMRC/WRAIR Raviprakash et al. Virology 2006;353:166-73

● Vector adenovirus - NMRC/WRAIR Raviprakash et al. J Virol 2008;82(14):6927-34

| 17

Main Candidate Vaccines in Clinical Development

Phase Developer # of

serotypes

Method Antigen Admin.

route

III Sanofi Pasteur

Tetravalent Atenuated, chimeric: DENV prME in YF vaccine virus 17D backbone

prM, E SC

II Inviragen Tetravalent Attenuated chimeric: DENV prME in attenuated DENV2 backbone

prM, E SC

I NIH (NIAID) Tetravalent DENV-4 30NT en 3’UTR deletion and chimerization

prM, E SC

I Merck Tetravalent Subunidad + Adyuvante Iscomatrix® E, NS1 IM

I NMRC Monovalent DNA (D1ME100) prM, E IM

I WRAIR Monovalent Inactivated DENV-1 Whole Virus IM

www.clinicaltrials.gov

| 18

0

2

4

6

8

10

12

14

16

18

20

Phase I Phase II Phase III

NIAID Sanofi Pasteur GSK Inviragen

AMR&MC Merck H. Biotech WRAIR

Dengue: Clinical Trials Published/ in ClinicalTrials.gov

Mainly monovalent formulations

www.clinicaltrials.gov. Ultimo acceso: Abril 2012 Guirakhoo et al. Human vaccines 2006;2(2):60-67 Morrison et al JID 2010;201:370-7 Poo et al PIDJ 2011;30(1):e9-e17 Capeding et al Vaccine 2011;29:3863-72

4

| 19

0

2

4

6

8

10

12

14

16

18

20

Phase I Phase II Phase III

NIAID Sanofi Pasteur GSK Inviragen

AMR&MC Merck H. Biotech WRAIRwww.clinicaltrials.gov. accessed: Abril 2012 Guirakhoo et al. Human vaccines 2006;2(2):60-67 Morrison et al JID 2010;201:370-7 Poo et al PIDJ 2011;30(1):e9-e17 Capeding et al Vaccine 2011;29:3863-72

Dengue: Clinical Trials Published/ in ClinicalTrials.gov

| 20

0

2

4

6

8

10

12

14

16

18

20

Phase I Phase II Phase III

NIAID Sanofi Pasteur GSK Inviragen

AMR&MC Merck H. Biotech WRAIRwww.clinicaltrials.gov. Ultimo acceso: Abril 2012 Guirakhoo et al. Human vaccines 2006;2(2):60-67 Morrison et al JID 2010;201:370-7 Poo et al PIDJ 2011;30(1):e9-e17 Capeding et al Vaccine 2011;29:3863-72

Dengue: Clinical Trials Published/ in ClinicalTrials.gov

| 21

non- st ruct ural genes C 5’ 3’

DEN

E prM

Sanofi Pasteur New Generation Dengue Vaccine

17D YF genome cl oned as cDNA

non- st ruct ural genes C E prM 3’ 5’

YF NS genes C E prM 3’ 5’

non- st ruct ural genes C 3’ 5’

E prM E prM

Dengue vi rus genome

| 22

non- st ruct ural genes C E prM 3’ 5’

Construction of CYD Dengue Vaccine

Ful l l engt h recombi nant cDNA RNA ( t ranscri pt i on)

RNA t ransf ect i on

Vero cel l s cul t ure

17 D YF replication “engine”

DEN envel ope prot ei ns

| 23

3’ 5’

3’ 5’

3’ 5’

3’ 5’

3’ 5’

17D YF virus

DNA 17 D YF vaccine virus

prM E DENV-1

WT PUO359

prM E DENV-2

WT PUO218

prM E DENV-3

WT PaH881/88

prM E DENV-4

WT 1228

Construction of CYD Dengue Vaccine

| 24

● Composition

● Live attenuated virus, tetravalent (4 vaccinal strains cultured in serum free Vero cells) 5

1 log10 CCID50 of each serotype

● Stabilizer without preservatives antibiotics or adjuvants

● Route of administration/Schedule

● Subcutaneous

● 3 injections 0 - 6 - 12 months

● Pharmaceutical form

● Powder and solvent for suspension for injection (0.5 ml)

● Indications

● Prevention of symptomatic dengue disease (from Dengue Fever to severe Dengue disease) due to serotypes 1, 2, 3 or 4

● Children and adults living in endemic areas, people working in (traveling to) endemic areas

● Priority: Endemic countries (Asia/Pacific, Latin America, Caribbean)

CYD Vaccine Characteristics

5

| 25

CYD Vaccine Clinical Development

Phase I studies

5 completed S&I studies in USA, Mexico, Philippines

Phase II studies

• 6 completed and 2 ongoing S&I studies in USA,

Australia, Latin America, Asia

• 1 ongoing PoC efficacy trial in Asia • 1 ongoing PoC co-ad. in Asia

Phase III studies

• 1 ongoing Lot-to-lot consistency in Australia

• 1 ongoing S&I study in Asia

• 2 ongoing S&I studies in Latin America • 2 ongoing efficacy studies in Asia and Latin America

• 2 ongoing co-ad. studies in Latin America

| 26

Safety Database

● Safety status as of March 28th 2012 ● Approximate Nbr of subjects who received at least one CYD dose

Over 28,000 individuals have already received at least one dose of CYD Dengue vaccine

Phase Toddlers Children Adolescents Adults Total

Phase I 0 140 71 185 396

Phase II 179 3368 474 893 4914

Phase III 839 10558 10411 1020 22828

Total 1018 14066 10956 2098 28138

| 27

● Reactogenicity profile similar to control vaccines

● No increase in reactogenicity

● In Flavivirus (FV)-immune subjects in comparison to FV naïve subjects

● After a 2nd or a 3rd dose

● In younger subjects (youngest group 2-11 years)

● No mild dengue-like syndrome observed

● Low vaccine viremia

● Similar rate of AEs and SAEs reported in Dengue vaccine group and

control

● No evidence to suggest a safety concern with the vaccine

Summary of Safety Data so far

| 28

Immunogenicity Database

● Immuno status as of March 28th ● Nbr of subjects immuno post dose 3 with unblind data available

Over 2,800 individuals have immune unblinded data after three doses of CYD Dengue vaccine

Phase Toddlers Children Adolescents Adults Total

Phase I 0 83 48 45 176

Phase II 0 576 437 245 1258

Phase III 0 659 485 290 1434

Total 0 1318 970 580 2868

| 29 29

Key Phase II Immunogenicity Results Post-Dose 3

GMTs

1

10

100

1000

CYD12 CYD22 CYD24 CYD28

GM

T

CYD12 CYD22 CYD24 CYD28

●USA ●Population

FV non inmune Adultss 18-45 y

● 101 subjects

CYD12

● Vietnam ●Population

DEN+/- y JE+/- Chldren/adults 2-45y

● 120 subjects

CYD22

●Singapore ●Population

DEN+/- Children/adults 2-45y

431 subjects

CYD28

●Peru ●Population

DEN+/- y YF+ Children 2-11 y

● 196 subjects

CYD24

% seropositive subjects

0

10

20

30

40

50

60

70

80

90

100

CYD12 CYD22 CYD24 CYD28

Ta

sa d

e s

ero

po

siti

vid

ad

(>

= 1

0l/d

il)

Seropositiviy ≥ 10

Serotype 1 Serotype 2 Serotype 3 Serotype 4

| 30

Summary of Immunogenicity Data so far

● Balanced immune response against all 4 serotypes after 3

doses of tetravalent Dengue vaccine

● Stepwise increase of seropositivity rates against each

serotype

● Higher immune responses observed in children

● Higher titers in subjects with previous flavivirus vaccination

● Higher titers in subjects previously exposed to wild type

dengue

6

| 31

Efficacy Clinical Trials

CYD15 Expanded Efficacy Study

Latin America

• Countries: Colombia, Mexico, Honduras,

Puerto Rico, and Brazil

• Age group: 9-16 years

• N subjects: ~20,000

CYD14 Expanded Efficacy Study

Asia

• Countries: Thailand, Indonesia, Malaysia,

Viet Nam, Philippines

• Age group: 2-14 years

• N subjects: ~10,000

CYD23 First Efficacy Study

• Country: Thailand

• Age group: 4-11 years

• N subjects ~4,000

| 32

Conclusions

● Dengue disease burden increasing globally

● Several dengue vaccines in development. Sanofi Pasteur CYD

vaccine the most advanced

● > 20 clinical trials completed or ongoing

● > 28,000 subjects received > 1 dose of CYD vaccine

● Favorable safety profile in children adolescents and adults

● Balanced neutralizing antibody response against 4 serotypes

● First efficacy trial in Thailand – Results available later in 2012 and

2 major efficacy trials (in Asia and Latin America) ongoing

| 33

Thank you!