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Dengue: About the Disease and Emerging Vaccines

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Gustavo Dayan, MDVaccine Preventable Diseases: Policy, Practices, PreparednessNew York City, NYJuly 23, 2012

Overview

● Dengue● Virus● Disease● Public health burden

● Vaccines in development● Live virus

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e us● Inactivated● Subunit● DNA/vector

● Sanofi Pasteur dengue vaccine● Clinical development ● Safety● Immunogenicity

•Flavivirus (YF, JE, TBE, WN) •Positive sense single stranded RNA (~11kb) that codes for 3 structural proteins & 7 non-structural proteins

Protéines de structure5’Non Codant

3’Non Codant

Protéines non stucturalesNSProtéines de structure5’Non Codant

3’Non Codant

Protéines non stucturalesNSStructural Proteins

5’NC 3’NCNon Structural Proteins Zhang et al., 2003,

Dengue Virus

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• 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

NS3C E NS1 NS2A NS2B NS4A NS4B NS5prM

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

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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)

DSS

DHF

DSS

DHF

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● 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)

Dengue Fever

Undifferentiated Fever

Asymptomatic

Dengue Fever

Undifferentiated Fever

Asymptomatic

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Courtesy Dr. S. Kalayanarooj

Adolescent diagnosed with dengue fever. Dengue Unit

Ratchaburi Hospital, Thailand – Feb 2011

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

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● 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.htmWHO - Dengue and dengue haemorrhagic fever, Fact sheet n 117, March 2009, available on: http://www.who.int/mediacentre/factsheets/fs117/en

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Global Dengue Risk

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

Dengue in the Americas, 1980-2010

1,00 0,000

1,20 0,000

1,40 0,000

1,60 0,000

1,80 0,000

R O

F C

AS

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

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

YEAR1998

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0

20 0,000

40 0,000

60 0,000

80 0,000

1980

1982

198 4

198 6

198 8

199 0

1992

1994

1996

1998

2000

2 002

2 004

2006

2008

201 0

Y EAR

NU

MB

E

YEAR 1981 CUBA 344,203

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

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

Dengue Incidence in the Americas, 1980-2010

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Dengue - Public Health Challenge

● WHO Neglected Tropical Diseases Group (WHA, Geneva - May 2012)

● Targets and milestones for control of neglected tropical

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● 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)

Dengue Prevention

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

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

Virus isolation(Hotta & Kimura)

Sabin & Schelsinger2W. Hammon3

US Army/Univ. Hawaii/Univ MahidolThailand

Attenuation of DEN viruses

LAV DEN1-4(1st generation)

Blanc & Caminopetros1

Killed & Attenuated DEN vaccines

Construction of chimericDEN4/DEN2(2nd generation)

Bray M. et al19915

Constructionof chimeric

YF/DEN2

Guirakhoo et al20006 Construction

of chimericYF/DEN1,3,4

Guirakhoo et al20017

Virus isolation and identification of serotypes

Dengue Vaccines

DEN3&4ManilaDEN1 Hawaii

DEN N. Guinea

Monovalent

Killed DEN vaccines

Simmons et al1

Virus isolation(Hotta & Kimura)

Sabin & Schelsinger2W. Hammon3

US Army/Univ. Hawaii/Univ MahidolThailand

Attenuation of DEN viruses

LAV DEN1-4(1st generation)

Blanc & Caminopetros1

Killed & Attenuated DEN vaccines

Construction of chimericDEN4/DEN2(2nd generation)

Bray M. et al19915

Constructionof chimeric

YF/DEN2

Guirakhoo et al20006 Construction

of chimericYF/DEN1,3,4

Guirakhoo et al20017

Virus isolation and identification of serotypes

Dengue Vaccines

DEN3&4ManilaDEN1 Hawaii

DEN N. Guinea

Monovalent

Killed DEN vaccines

Simmons et al1

History of Dengue Vaccines

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19441943 19561944-45 1970 -’80

Sabin, Schelsinger2

/Univ MahidolThailand/Fund. Rockefeller4

1928-1930

Caminopetros1

1990 - 2000BZ 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):5-115: J Virol 1996;70:4162-6 6: J Virol 2000;74:3020-8 7: J Virol 2001;75:7290-7304

LAV DEN1

19441943 19561944-45 1970 -’80

Sabin, Schelsinger2

/Univ MahidolThailand/Fund. Rockefeller4

1928-1930

Caminopetros1

1990 - 2000BZ 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):5-115: J Virol 1996;70:4162-6 6: J Virol 2000;74:3020-8 7: J Virol 2001;75:7290-7304

LAV DEN1

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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

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● 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

Dengue Vaccines in Development

● Live virus vaccinesTraditional attenuationRecombinant

● Inactivated vaccines

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Inactivated vaccines● Subunit vaccines● DNA vaccines● Vector vaccines

Candidate Vaccines I -- Live Virus Vaccines

● Traditional attenuation● Cell culture passages

• PDK, PRhL cells - WRAIR/GSKSun 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

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• 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

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Candidate Vaccines II

● Inactivated vaccines - WRAIR/GSKPutnak 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

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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

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 prM E SC

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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

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Dengue: Clinical Trials Published/ in ClinicalTrials.gov

Mainly monovalent formulations

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0

2

4

6

Phase I Phase II Phase III

NIAID Sanofi Pasteur GSK Inviragen

AMR&MC Merck H. Biotech WRAIRwww.clinicaltrials.gov. Ultimo acceso: Abril 2012Guirakhoo et al. Human vaccines 2006;2(2):60‐67Morrison et al JID 2010;201:370‐7Poo et al PIDJ 2011;30(1):e9‐e17Capeding et al Vaccine 2011;29:3863‐72

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8

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12

14

16

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Dengue: Clinical Trials Published/ in ClinicalTrials.gov

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0

2

4

6

Phase I Phase II Phase III

NIAID Sanofi Pasteur GSK Inviragen

AMR&MC Merck H. Biotech WRAIRwww.clinicaltrials.gov. accessed: Abril 2012Guirakhoo et al. Human vaccines 2006;2(2):60‐67Morrison et al JID 2010;201:370‐7Poo et al PIDJ 2011;30(1):e9‐e17Capeding et al Vaccine 2011;29:3863‐72

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10

12

14

16

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Dengue: Clinical Trials Published/ in ClinicalTrials.gov

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0

2

4

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Phase I Phase II Phase III

NIAID Sanofi Pasteur GSK Inviragen

AMR&MC Merck H. Biotech WRAIRwww.clinicaltrials.gov. Ultimo acceso: Abril 2012Guirakhoo et al. Human vaccines 2006;2(2):60‐67Morrison et al JID 2010;201:370‐7Poo et al PIDJ 2011;30(1):e9‐e17Capeding et al Vaccine 2011;29:3863‐72

non-structural genesC5’ 3’EprM

Sanofi Pasteur New Generation Dengue Vaccine

17D YF genome cloned as cDNA

YF NS genesC EprM 3’5’

Dengue virus genome

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DEN

non-structural genesC EprM 3’5’

non-structural genesC 3’5’

EprMEprM

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non-structural genesC EprM 3’5’

Construction of CYD Dengue VaccineConstruction of CYD Dengue Vaccine

Full length recombinant cDNA RNA (transcription)

RNA transfection

DEN envelope proteins

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Vero cells culture

17 D YF replication “engine”

3’5’

3’5’

17D YF virus

prM E DENV‐1

WT PUO359

prM E DENV‐2

WT PUO218

Construction of CYD Dengue Vaccine

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3’5’

3’5’

3’5’

DNA 17 D YF vaccine virus

prM E DENV‐3

WT PaH881/88

prM E DENV‐4

WT 1228

● 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

CYD Vaccine Characteristics

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● 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)

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CYD Vaccine Clinical Development

Phase I studies5 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

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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

Safety Database

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

Phase Toddlers Children Adolescents Adults Total

Phase I 0 140 71 185 396Phase II 179 3368 474 893 4914

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

Phase III 839 10558 10411 1020 22828Total 1018 14066 10956 2098 28138

● 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)

Summary of Safety Data so far

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● 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

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Immunogenicity Database

● Immuno status as of March 28th

● Nbr of subjects immuno post dose 3 with unblind data available

Phase Toddlers Children Adolescents Adults Total

Phase I 0 83 48 45 176Phase II 0 576 437 245 1258

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

Phase II 0 576 437 245 1258Phase III 0 659 485 290 1434

Total 0 1318 970 580 2868

Key Phase II Immunogenicity ResultsPost-Dose 3

GMTs

1

10

100

1000

GM

T

●USA●Population

FV non inmune Adultss 18‐45 y

● 101 subjects

CYD12●Peru●Population

DEN+/‐ y YF+Children 2‐11 y

● 196 subjects

CYD24

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1CYD12 CYD22 CYD24 CYD28

CYD12 CYD22 CYD24 CYD28

● Vietnam●Population

DEN+/‐ y JE+/‐Chldren/adults 2‐45y

● 120 subjects

CYD22●Singapore●Population

DEN+/‐Children/adults 2‐45y 

431 subjects

CYD28

% seropositive subjects

0

10

20

30

40

50

60

70

80

90

100

CYD12 CYD22 CYD24 CYD28

Tasa

de

sero

posi

tivid

ad (>

= 1

0l/d

il)

Seropositiviy ≥ 10

Serotype 1 Serotype 2 Serotype 3 Serotype 4

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

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● Higher immune responses observed in children

● Higher titers in subjects with previous flavivirus vaccination

● Higher titers in subjects previously exposed to wild type

dengue

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Efficacy Clinical Trials

CYD15 Expanded Efficacy StudyCYD15 Expanded Efficacy StudyLatin AmericaLatin America• Countries: Colombia, Mexico, Honduras,

Puerto Rico, and Brazil• Age group: 9-16 years• N subjects: ~20,000

CYD14 Expanded Efficacy StudyCYD14 Expanded Efficacy StudyAsiaAsia• Countries: Thailand, Indonesia, Malaysia,

Viet Nam, Philippines• Age group: 2-14 years• N subjects: ~10,000

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CYD23 First Efficacy StudyCYD23 First Efficacy Study• Country: Thailand• Age group: 4-11 years• N subjects ~4,000

Conclusions

● Dengue disease burden increasing globally

● Several dengue vaccines in development. Sanofi Pasteur CYD vaccine the most advanced

● > 20 clinical trials completed or ongoing

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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

Thank you!

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