Controlled Human Malaria Infection

Controlled Human Malaria Infection:
Strength of a human challenge model
Robert Sauerwein
)
Plasmodium life cycle in human host
Clinical symptoms
& Pathology
2
Controlled Human Malaria Infection (CHMI)
Liver stage
Infective
mosquito bite
Blood stage
Microscopy positive
 treatment
End of
study
R. Sauerwein et al. Nat Rev Immunol 2011
Parasitaemia after CHMI
RTQ-PCR N=48
• Parasitemia in 100% of the
volunteers
Treatment
• Microscopy: Thick smear
positive day 7-12
Microscopy
• RTQ-PCR: Cyclic growth of
parasites
Treatment
N=48
Parasitaemia after CHMI
RTQ-PCR N=48
• Parasitemia in 100% of the
volunteers
Treatment
• Microscopy: Thick smear
positive day 7-12 (sensitivity
Microscopy
N=48
4000 par/ml)
• RTQ-PCR: Cyclic growth of
parasites (sensitivity 20 par/ml)
Treatment
Hermsen C et al. MBP: 2001
Parasitaemia by qPCR after bites of 5 infected mosquitoes
in 7 CHMI trials in a total of 64 volunteers.
+ microscopy
for parasites
post- infection
Sauerwein R et al, unpublished
Controlled Human Malaria infection (CHMI)
Thick smear (4000Pf/ml))
qPCR
bites of 5 Pf NF54
infected mosquitoes
(20 Pf/ml)
Treatment at thick-smear positive
2
4
Liver-stage
6
8
10
12
14
16
18
20
22
24
blood-stage
Data from 48 volunteers in 7 CHMI trials
Roestenberg et al., JID, 2012
Sauerwein R et al, Nat Rev Immunol 2011
Statistical model Fitting the data into THE MODEL
100000
1 + # Pf / ml
10000
1000
100
10
1
4
5
6
7
8
9
10
11
Days after infection
Hermsen C et al AMJTMH 2004
Estimated parasitological parameter values
# Hepatocytes infected:
207 (29-560)
Asexual cycle
43.7 hrs (42.2-45.6)
rings
28.3 hrs
mature trophs
15.4 hrs
Multiplication factor :
7.50 (6.1-9.6)
Pre-patent period :
MPS
8.8 days (7.3-10.3)
PCR
6.8 days (6.7-7.3)
Hermsen C et al AMJTMH 2004:71:196
Simulated kinetics of parasitemia for different vaccine efficacies
(a) Pre-erythrocytic vaccine
1000000
0%
60%
95%
99%
Liver-stage vaccine
1 + # Pf / ml
100000
10000
1000
100
10
1
4
6
8
10
12
Days after infection
Bloodstage vaccine
1 + # Pf / ml
100000
0%
30%
60%
90%
(b) A-sexual stage vaccine
1000000
10000
1000
100
10
Hermsen C et al AMJTMH 2004:71:196
1
4
6
8
10
Days after infection
12
Harmonization of Design and Conduct of CHMI
by Mosquito bite
CHMI Mosquito Centers in the world:
1.
USMMVP, US
2.
Sanaria/ NIH/ University of Maryland, US
3.
Seattle Biomedical Research Institute , US
4.
Oxford University, UK
5.
Radboud University Medical Centre,NL
Input from USAID, US FDA, NIAID, PATH MVI, EC and EVI.
Input from WHO committees
Meetings: Bethesda, MD, USA in March 2009; Arusha, Tanzania March 2010 ; Washington, DC in June
2010 (WHO); Amsterdam, June 2011 (EMVDA)
PfSPZChallenge: aseptic cryopreserved sporozoites
(Sanaria)
PfSPZ challenge
• Advantage:
• Easy access for global application in appropriate clinical settings.
•
RadboudUMC, NL, Oxford University, UK, Tuebingen University, Germ. CRESIB, Spain, NIH, US. U. Maryland, US, IHC,
Tanzania, KEMRI, Kenya ,MRTC, Mali, etc
•
: However:
30-100 fold less potent compared to Pf-infected mosquitoes bites:
• Viability/potency
• Administration (route, device, volume)
13
In vivo imaging of Pb GFP-Luccon parasites
Intravenous versus intradermal injection of sporozoites
i.v injection
i.d injection
44 hrs post
infection
Ploemen I. et al: Vaccine 2103
Administration of aseptic cryopreserved sporozoites
(Sanaria)
Direct intravenous inoculation
Bypass the skin
3200 Spz (30-60 mosquitoes)
•5-10x more potent than ID or IM
•Bypass of immune interference
against spz in the skin
Administration of Pf-infected red blood cells intravenously
Centres:
•QIMR, Austr.
•Oxford University, UK
•RadboudUMC, NL
Cheng AMJTMH 1997; Pombo Lancet 2002
Sanderson AMJTMH 2008, Bijker PNAS 2013
Parasite growth after blood stage
infection
PCR determined parasite growth curves
10,000,000
1,000,000
Parasites/ml
100,000
10,000
Subject 1
Subject 2
Subject 3
1,000
Subject 4
Subject 5
100
10
1
3.5
4
4.5
5
5.5
6
6.5
7
7.5
8
8.5
9
Days after inoculation
Sanderson et al. AJTMH 2008; 878
Blood stage challenge
• Advantage:
• Measurement of 4-5 asexual multiplication cycles (compared to 2-3
cycles after mosquito challenge)
• However:
• Inoculum (1800 iRBC) is unphysiologically low:
10-20x lower than iRBC from 1 infective spz
• Is missing sporo/pre-erythrocytic and cross stages antigens
• blood stage and sporo/liver stages: LSA3, AMA1, MSP1……
• Potential induction of immune responses by very low
parasitemia trivial?
18
CHMI model:
Infection
but
what about protection?
The hunt for Correlate of Protection
RTS/S Sub-unit vaccine
Interim Results Efficacy Phase IIb/III trial
• RTS/S: P. falciparum CSP
fused to HBsAg/AS01E
Protection:
30-50%
NEJM 2011 365:1863; NEJM 2012 367 2283; NEJM 2013 368:1111
Thera et al NEJM 2011;365:1004
www.who.int/vaccine_research/links/Rainbow/en/index.html
Efficacy CHMI parallels Phase IIb/III outcome
20
Limited success of these subunit
vaccines
• Poor immunogenicity of individual antigens,
Adjuvants; Viral platforms; Prime boost strategies
• Antigenic diversity of the selected target proteins
Genetic diversity coverage
• Insufficient breadth and coverage of the induced
immune response based on mostly single antigens.
Antigen Mix/ Match or Attenuated whole parasite
Chemo-Prophylaxis and Sporozoites (CPS)
Immunization
Chloroquine
Chloroquine Prophylaxis and Sporozoites (CPS) Immunization
Parasitemia post Challenge
CPS Immunization
qPCR
Chloroquine prophylaxis (3 months)
3 x 12-15 PfSpz infected mosquito-bites
5 PfSpz infected mosquito-bites
Roestenberg & McCall et al., NEJM, 2009
Roestenberg et al., Lancet, 2011
Protection after CPS-immunization
CPS-immunization induces 100% homologous protection.
Roestenberg & McCall et al., NEJM, 2009
CPS-induced protection is immunization dose-dependent
19/20
8/9
3/5
5/10
Roestenberg & McCall et al., NEJM, 2009
Bijker & Bastiaens et al., PNAS, 2013
Bijker & Teirlinck et al., JID 2014
Dissect CPS-induced immune signature
1. Which immune responses are induced by CPS-immunization?
2. Can any of these immune responses correlate with sterile
protection from re-infection?
Antigen targets of CPS-induced antibodies
Comparing CPS Antibody profile with semi-immune Kenyan sera
LSA1
MSP2
MSP10
MSP1
MSP (H101)
MSP11
LSA3
CSP
CPS Immune Reactive
84 Antigens
Pre-erythrocytic
antigens
Reactive in Both
90 Antigens
Cross-stage
antigens
Semi-Immune Reactive
238 Antigens
Blood stage
antigens
Felgner Ph et al Sci Rep 2013
Immune Correlate of Protection
Chemo-Prophylaxis and Sporozoites (CPS)
Analysis of cellular immune responses
 Antibodies
 CD4 T cells:
 IFNγ +/- IL-2
 CD8 T cells:
 IFNγ
 Cytotoxicity
 CD107a: degranulation marker
 Granulysin / Granzyme B: cytotoxic molecules
Cytotoxic immune responses in vitro
after CPS immunization (C-1).
Bijker E et al. JID 2014
The RUMC Clinical Malaria Program after >300 CHMI
Controlled human Malaria Infections (CHMI):
• Major upgrade by introduction of molecular detection of parasites by
qPCR and development of statistical model
Chemo-Prophylaxis and Sporozoite (CPS) immunization :
• Simple and novel immunization regime inducing long lasting sterile
protection with 95% efficacy
• “Better than Nature “ immunzation protocol challenges dogma’s on
naturally acquired malaria immunitity
• Biomarker for protection: First steps in delineation of protective
immune signatures
• Identification of (new) target antigens for protection by system
immunological approach
Many modalities of
Controlled Human Malaria Infections
and thus
a Fit-for-Purpose Model
Pagina 31
CCMS-the Netherlands:
RUMC /LUMC/EMC
Malaria Vaccine Team
Clinical team
Else Bijker
Guido Bastiaens
Matthew McCall
Meta Roestenberg
Jorien Wiersma
Linda Wammes
Remko Schats
Quirijn de Mast
Andre van der Ven
Leo Visser
Perry van Genderen
Diagnostic team
Rob Hermsen
Theo Arens
Karina Teelen
Lisette van Lieshout
Jaco Verweij
Jaap van Hellemond
Collaborators
•Sanaria
SL Hoffman
Immunology team
Anne Teirlinck
Wiebke Nahrendorf
Marije Behet
Anja Scholzen
Parasite team
Marga vd Vegte-Bolmer
Rianne Siebelink-Stoter
Wouter Graumans
Mosquito team
Geert-Jan van Gemert
Laura Pelser-Posthumus
Astrid Pouwelsen
Jacqueline Kuhnen
Jolanda Klaassen
STPH Basel/ Bagamoyo
S. Shekalaghi
C Daubenberger
INSERM
Dominique Mazier
J-F. Franetich
•UC Irvine:
Ph. Felgner
•CEVAC – Ghent
L Foquet
G Leroux-Rouls
GAP team
Ben van Schaijk
Martijn Vos
Ivo Ploemen
Takechi Annoura
Shahid Khan
Chris Janse
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