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Prof. anzala hiv vaccine update
1. KAVI-INSTITUTE OF CLINICAL RESEARCH
(KAVI-ICR)
UNIVERSITY OF NAIROBI
Prof .Omu Anzala
Update: HIV Vaccine Research
2. 07/11/13 09:07 AM 2
OUT LINE OF PRESENTATION
• Introduction
• Current global position
• Current science in vaccine
development
3. 07/11/13 09:07 AM 3
PrEP
Clean injecting
equipment
Cervical barriers:
vaginal diaphragms
Prevention of
vertical transmission
Vaccines
Voluntary
counselling and
testing
Microbicides
Treatment
as prevention
Male
circumcision
PEP
Comprehensive HIV
prevention
Male and female condoms
ARV
4. 07/11/13 09:07 AM 4
Research at KAVI
Protocols A, B, (DBS), C
(EIR) , G, J, I
Protocols A, B, C, D Protocols 002/4/8/10, V001,
B002/3 PrEP,/004
Protocols M,
H, LTFU
5. 07/11/13 09:07 AM 5
Public
sector,
academia
Pharmaceutical companies,
product-development
partnerships
Research & Development :
Basic
research
Applied
research
Preclinical
development
Clinical
development
Advanced
development
Large-scale
Efficacy trials
R&DR&D
R&D Strategy:
Address key gaps to improve the pipeline by integrating vaccine discovery and
development
R&D Strategy:
Address key gaps to improve the pipeline by integrating vaccine discovery and
development
6. 07/11/13 09:07 AM 6
4 vaccine efficacy trials: What have we
learned ?
• Vaxgen gp 120 (No efficacy)
– Induced weak neutralizing antibodies
• STEP Merck Ad5 gag-pol-nef (No efficacy)
– Cellular response but not broad and sustained
– Evidence of protection against vaccine matched viral strains in vaccine recipients in vivo
and in vitro
• RV144 Canarypox + gp 120 (31% reduction of HIV-1 acquisition with no viral load effect)
– Induced antibody responses
– Correlates analysis (V2 specific region antibody binding)
• HVTN 505 Ad5 gag-pol-nef and DNA ( No efficacy)
- stop due to futility
- No evidence of protection
- (Similar results as the step and Phambili trial in 2007)
7. 07/11/13 09:07 AM 7
1.AIDS vaccine shows first efficacy in clinical
trials
2.Replicating viral vector effective in controlling
SIV in animal studies
3.Multiple new antibodies and targets on HIV
discovered
State of the HIV Vaccine field
8. 07/11/13 09:07 AM 8
Prevention of HIV:
A vaccine that elicits broadly neutralizing
antibodies
9. 07/11/13 09:07 AM 9
Challenges of Developing
a Vaccine
• Pathogen
-Physical Compositions
-Life Cycle
•Pathogen Interactions
- Nature of Infection
(disease, immunity<>protection)
10. 07/11/13 09:07 AM 10
HIV Variability: The major scientific challenge for
HIV vaccine
Source: Weiss, R.A. (2003)
Genetic variability of
global influenza A virus
(1996)
Genetic variability of
HIV-1 V2-C5
(Congo, 1996)
Size = Extent of HIV
variability
13. 07/11/13 09:07 AM 13
A broadly neutralizing antibody is defined by:
•Breadth: how many type of HIV (or strains) can it block? The
more the better.
•Potency: how well will it inhibit (the less amount of antibody
needed the more potent).
What are broadly neutralizing antibodies?
14. 07/11/13 09:07 AM 14
Infected individual
Broadly neutralizing
(protective)
antibodies
Ag
Molecular
characterization
of interaction of
antibody
with pathogen antigen
Modified antigen
Immunogen design
and testing
Combination of several
immunogens = vaccine
Source: Adapted from Burton, Nat. Rev. Immunol., 2:706, 2002
*
*
Retrovaccinology: From antibody to antigen
Vaccine volunteer
15. 07/11/13 09:07 AM 15
Targets for HIV Vaccine Design: Major Sites
on HIV identified by broadly neutralizing antibodies
against HIV
membrane proximal
domain + lipid
Dual glycan, V3
(2G12, PGT 120-135)
CD4 binding site
(b12, VRC01, PG04,
CH31)
V1V2
Peptide-glycan
(PG9/16, CH01)
(2F5, 4E10)
16. 07/11/13 09:07 AM 16
How do we get broadly neutralizing
antibodies?
ANTIBODY MATURATION IN HIV INFECTION
Weeks to
Months
Years
VACCIN
E
Weeks to
Months
17. 07/11/13 09:07 AM 17
Control of infection:
A vaccine that elicits cellular immune responses
18. 07/11/13 09:07 AM 18
∆nef-Vaccinated
Single Cycle
SIV (sc SIV)
Live Vaccines control SIV in monkeys infection
better than other approaches
PlasmaViralLoad(RNAceq/mL)
Weeks Post Challenge
101
102
103
104
105
106
107
108
0 10 20 30 40 50 60
Jia PLOS Pathogens 2009
No
Vaccine
Live vaccines are among the
most effective (measles, polio,
mumps)
Live HIV vaccines will not be
developed due to safety
considerations
How can we mimic the efficacy
of live attenuated vaccines
while maintaining safety for
global use ?
REPLICATING VECTORS
19. 07/11/13 09:07 AM 19
What are replicating vectors?
Time post vaccinationTime post vaccination
Single cycle vector (current
vectors: Ad35, Ad26)
Replication competent (coming vector)
20. 07/11/13 09:07 AM 20
Neutralizing Abs Cell Mediated
Immunity (CMI)
• Block virus entry: induction of antibody response (likely broadly
neutralizing)
• Block virus replication post-entry: induction of cellular response
(CMI)
An effective HIV vaccine will likely need to induce
two “types” of immune responses
21. 07/11/13 09:07 AM 21
1. Advance
current
candidates
through clinical
trials
PROOF
OF CONCEPT
SAFETY AND
IMMUNOGENICITY
EFFICACY
DATA
2. Advance next
generation
improved vector
candidates
3. Develop
candidates to
elicit broadly
neutralizing
antibodies
Near
term/mode
rate
impact
Longer
term/high
impact
Recombinant vector platform
Replicating vectors
HIV Envelope
Goals for Research & Development
MILESTONES BY 2015
22. 07/11/13 09:07 AM 22
• Ad26 + MVA (mosaic antigens)
• Chimp Ad 63 + MVA HIVconsv (conserved antigens)
• epDNA + IL12+ Ad35 or chAd63
• DNA + MVA (Multiple)
• DNA + Tiantian-VV
• Electroporated DNA
• MVA (multiple)
• HIV ENV trimers
• Designed Immunogens
• AAV –bnAb delivery
•Measles virus
•Attenuated VSV
•Vaccinia virus Tiantan
•Sendai
•CMV
•CDV
•VSV
•Pox
•Adeno
Improving RV-
144: CMI + non-
neutralizing Ab
Improving RV-
144: CMI + non-
neutralizing Ab
Prime Boost
Candidates-
improve the
breadth of
vaccine
Prime Boost
Candidates-
improve the
breadth of
vaccine
Candidates to
Elicit bnAbs
Candidates to
Elicit bnAbs
Replicating
Vectors- for
durable
responses to
mimic live
attenuated
Replicating
Vectors- for
durable
responses to
mimic live
attenuated
DNA + Ad5 (gag-pol, nef-Env A,B.C) :
Phase IIb Efficacy (HVTN 505) 2009-2014
ALVAC + gp120/MF59 Licensure RSA (planned 2015)
DNA + NYVAC + gp120 Test of Concept Trial
NYVAC + gp120 (planned 2015)
The Global HIV Vaccine Landscape
- 2013
ALVAC + gp120 Licensure Trial in Thailand (planned 2015)
Basic
research
Applied
researc
h
Preclinical
development Phase I / II Large-scale Efficacy
trials
23. 07/11/13 09:07 AM 23
IAVI and Partners in 2013
Immunogen
Designs to
Elicit bnAbs
Replicating
Vectors
Product
Development
& Clinical
Trials
ChAd63/MVAChAd63/MVA
eOD; iVSV; JFRL,
BG505
eOD; iVSV; JFRL,
BG505
VSV
CDV
VSV
CDV
AAV-PG9AAV-PG9
Sendai vectorSendai vector
23
24. 07/11/13 09:07 AM 24
IAVI’s most advanced replication competent vector
Sendai virus based vector:
Replication competent vector; naturally infect mice but not pathogenic in humans
Phase-1 due to start by end of 2012 beginning of 2013 would include our partners in:
Kenya
Rwanda
UK
Prime-boost regiment with SeV(Gag) and Ad35(GRIN) vectors
Strong focus on mucosal responses with KAVI as center of excellence for mucosal
immunity
Other replicating vectors in development:
Canine Distemper virus (CDV)
CMV partnership with L. Picker as part of the new Central Service Facility
25. 07/11/13 09:07 AM 25
BOO2
BOO3
BOO4
Current HIV vaccine research at KAVI-ICR
26. 07/11/13 09:07 AM 26
On-going or Just-completed Phase 1 studies at KAVI
IAVI sponsored Clinical Trials
IAVI B002 Ad35-GRIN + Adjuvanted Protein
–Kenya, Uganda and Zambia
IAVI B003 Ad35- ENV + Ad26- ENV
–USA, Kenya, Rwanda and South Africa
IAVI B004 DNA IL-12 EP + Ad35-GRIN/ENV
–Kenya, Uganda and Rwanda
27. 07/11/13 09:07 AM 27
Summary KAVI’s Experience with Vaccine studies
Study title Product
[route of
administration]
Number of
volunteers
[retention]
%
women
Study
Dates
Timelines
(# days to
enrol 1 vol)
IAVI 002 DNA [IM1
] 18 [94%] 17% 2001- 2002 4.9
IAVI 004 MVA [ID] 18 [94%] 11% 2002- 2005 8.5
IAVI 010 DNA + MVA [IM/ID] 70 [99%] 17% 2003- 2005 2.7
IAVI V001 Multi-clade
DNA/Ad5 [BJ/IM]
57 [98%] 39% 2006- 2007 2.5
IAVI B002 F4co-AS01/ Ad35
[IM]
40 [100%] 28% 2011 -
2012
3.1
IAVI B003 Ad26/Ad35 [IM] 40 [100%] 33% 2011-2012 2.4
IAVI B004 DNA/Ad35[IM/EP] 25 [96%] 40% 2012-2013 1.1
28. 07/11/13 09:07 AM 28
IAVI PROTOCOL B004
Phase I double blind, randomized, placebo-controlled trial to Evaluate the Safety and
Immunogenicity of a Multiantigen HIV (HIV-MAG) plasmid DNA (pDNA) Vaccine co-
administered with Recombinant Human IL-12 pDNA (GENEVAX® IL-12) followed or
preceded by Recombinant Ad35-GRIN/ENV HIV Vaccine in HIV-Uninfected, Healthy
Volunteers
29. 07/11/13 09:07 AM 29
Fresh semen
Non-invasive mucosal sampling
from among volunteers enrolled in
the three vaccine studies
Rectal sponge
Vaginal/cervical
Saliva
Semen
Mucosal Studies: Development of immune mucosal
assays
30. 07/11/13 09:07 AM 30
Vaccines can take decades to develop
Measles
Hepatitis B
Human papilloma virus
(cervical cancer)
Rotavirus
(diarrheal disease)
Varicella zoster
(chickenpox)
Pertussis
(whooping cough)
Polio
Haemophilus influenza
Typhoid
Malaria
Human immunodeficiency virus
(HIV/AIDS)
INFECTIOUS AGENT
(Disease)
AGENT LINKED
TO DISEASE IN
…
VACCINE
LICENSED
IN U.S. IN …
1953
1965
1884
1973
1953
1906
1908
1889
Early ’80s
to
mid-’90s
1893
1983
1963
1981
2006
2006
1995
1948
1955
1981
1989
—
—
YEARS
ELAPSED
10
16
12-25
33
42
42
47
92
105
116
26
33. 07/11/13 09:07 AM 33
Rationale for the Protein-based and Prime boost combinations
IAVI PROTOCOL B002
Protein-Based Vaccines
–Not limited by pre-existing immunity to vectors
–When formulated with appropriate adjuvants, can elicit potent and
broad-based immune responses (Antibody, CD4+ T cell responses)
Recombinant Viral Vector Based Vaccines
–Can elicit CD8+ T cells to HIV-1 proteins
Prime-Boost (PB) vaccine regimen
–Two vaccines could potentially show additive and possibly
synergistic priming and boosting effect
34. 07/11/13 09:07 AM 34
What is the B003 trial?
Candidate Vaccines consists of
Ad35 ENV- Recombinant replication-incompetent adenovirus serotype
35 expressing HIV-1 subtype A gp140 env gene
Ad26.ENVA.01 is a recombinant replication deficient adenovirus
serotype 26 expressing HIV-1 A gp140 env gene
Both vectors code for HIV-1 Clade A gp140 Env glycoprotein
35. 07/11/13 09:07 AM 35
Rationale for IAVI Protocol B003
IAVI PROTOCOL B003
Choice of Viral vectors
Vector serotypes were chosen due to the low likelihood of past community exposures and
pre-existing (serotype) immunity. (Ref. Dan Barouch Havard U)
76%
21%
3% 0%
<16
16-200
200-1000
>1000
NAb Titers
76%
21%
3% 0%
<16
16-200
200-1000
>1000
N A b T i t e r s
0%
31%
21%
48%
83%
13%
3%1%
79%
17%
4%0%
97%
2%
1%
0%
78%
21%
1%0%
Ad5 Ad35
Ad26 Ad48 Ad49
Comparative Adenovirus Seroprevalence in Adults
from Sub-Saharan Africa (N=200; 18-65 yrs)
81%
12%
5% 2%Ad50
36. 07/11/13 09:07 AM 36
B003 Trial Schema- Part 1 BOSTON SITE
Group Vaccines N Month 0 M3 M6
A Ad26 →
Ad35
13 (10/3) Ad26 - Ad35
B Ad35 →
Ad26
13 Ad35 - Ad26
C Ad26 →
Ad35
13 Ad26 Ad35 -
D Ad35 →
Ad25
13 Ad35 Ad26 -
Total 52 (40/12)
Evaluating
o Heterologous design
o Two different vaccine intervals
37. 07/11/13 09:07 AM 37
B003 Trial Schema- Part II East and South African
Sites
Group Vaccines N
(Each grp)
M0 M3 M6
E & I Ad26 →
Ad26
13 (10/3) Ad26 Ad26
F & J Ad35 →
Ad35
13 Ad35 Ad35
G & K Ad26 →
Ad35
13 Ad26 Ad35
H & L Ad35 →
Ad25
13 Ad35 Ad26
Total 104 (80/24)
Evaluating
o Heterologous and homologous design
o One vaccine interval
38. 07/11/13 09:07 AM 38
B004 Vaccine Candidates
Ad35-GRIN/ENV Vaccine consists of
Ad35-GRIN- Recombinant replication-incompetent adenovirus serotype
35 expressing HIV-1 subtype A gag, reverse transcriptase, integrase,
nef genes
Ad35 ENV- Recombinant replication-incompetent adenovirus serotype
35 expressing HIV-1 subtype A gp140 env gene
HIV-MAG VACCINE consists of two DNA plasmids
HIV-1 subtype B gag/pol DNA plasmid
HIV-1 subtype B nef/tat/vif, env (gp160)
39. 07/11/13 09:07 AM 39
Special Features of IAVI Protocol B004
IAVI PROTOCOL B004
GENEVAX® IL-12 pDNA (naturally occurring) as molecular
adjuvant
• Adjuvant: to improve the immunogenicity of DNA vaccines
• HIVMAG vs HIVMAG + IL12
• 2 dosage levels of IL12
Route: Intramuscular by electroporation (IM/EP)
to improve efficiency of delivery of DNA vaccine
40. 07/11/13 09:07 AM 40
Rationale for IAVI Protocol B004
IAVI PROTOCOL B004
HIV DNA Vaccines
Not limited by pre-existing immunity to vectors
Safe and well tolerated, BUT weakly immunogenic in humans
to improve the immunogenicity/efficiency of delivery
-Adjuvants (e.g.; molecular such as IL-12)
-Electroporation
Recombinant Viral Vector Based Vaccines (Ad35)
Elicit CD8+ and CD4+ T cells to HIV-1 antigens
Ad35 tested in previous vaccine studies and safe to date
Prime-Boost (PB) vaccine regimen
DNA vaccines no stand-alone vaccines
Improve cellular and humoral (Ab) immune responses
41. 07/11/13 09:07 AM 41
B004 Study Design
Months 0, 1, 2 Month 6
Study Groups
N
vaccine / placebo
Prime Vaccine
(dosage, delivery)
Boost Vaccine
(dosage, delivery)
1 12/3
HIV-MAG
(3,000mcg) (IM/EP*)
Ad35-GRIN/ENV
(2x1010
vp, IM)
2 12/3
HIV-MAG (3,000mcg) +
GENEVAX® IL-12 (100mcg) (IM/EP*)
Ad35-GRIN/ENV
(2x1010
vp, IM)
3 12/3
HIV-MAG (3,000mcg) +
GENEVAX® IL-12 (1000mcg) (IM/EP*)
Ad35-GRIN/ENV
(2x1010
vp, IM)
Month 0 Month 4
4 12/3
HIV-MAG (3,000mcg) +
GENEVAX® IL-12 (1000mcg) (IM/EP*)
Ad35-GRIN/ENV
(2x1010
vp, IM)
5 12/3
Ad35-GRIN/ENV
(2x1010
vp, IM)
HIV-MAG (3,000mcg) +
GENEVAX® IL-12
(1000mcg) (IM/EP*)
Total 75
(60/15)
*HIVMAG +/- IL12: Each EP vaccination time point requires 2 administrations
42. 07/11/13 09:07 AM 42
42
Electroporation Mediated DNA Vaccine Delivery
Intracellular delivery of DNA inducing expression of the encoded
antigen by the recipient’s own cells
DNA vaccine Somatic cells Endogeneous antigen
production
Key Considerations:
• Intracellular uptake of DNA essential for antigen expression
• Conventional injection of DNA results in low efficiency uptake
•EP disturbs phospholipid layer of membrane causing transient increase
cell membrane permeability
• Enhances DNA potency by 2-3 orders of magnitude
•DNA doses of up to 4.0mg (bilateral administration)
44. 07/11/13 09:07 AM 44
IAVI B002 Trial Study Design
Phase I double blinded, placebo-controlled, randomized trial with F4co
adjuvanted with AS01B or AS01E (1/2 strength of AS01B) administered
with Ad35-GRIN (1011
vp ) in African Collaborating Research Centers
• . Months
N Vaccine/
Placebo
0 1 3 4
A 32/8
F4co10 ug
/ AS01E
F4co 10 ug
/ AS01E
Ad35-GRIN
1011
vp
B 32/8
F4co 10
ug / AS01B
F4co 10 ug
/ AS01B
Ad35-GRIN
1011
vp
C 32/8
Ad35-GRIN
1011
vp F4co 10 ug
/ AS01E
F4co 10
ug / AS01E
D 32/8
Ad35-GRIN
1011
vp F4co 10
ug / AS01B
F4co 10 ug
/ AS01B
vp: viral particles
45. 07/11/13 09:07 AM 45
B002 HIV vaccine Candidates
Vaccine candidate: F4co/AS01
Recombinant fusion protein to target conserved regions of HIV
comprised of p24-RT-Nef-p17
Adjuvant System AS01
Two immunostimulants (Glycoside from Quillaja saponaria 21 & 3-D
monophosphoryl lipid A)
Ad35-GRIN- Recombinant replication-incompetent adenovirus serotype 35
expressing HIV-1 subtype A gag, reverse transcriptase, integrase, nef
genes
F4co: Fusion protein of p24/RT/Nef and p17 (Clade B HIV-1)
RT (mutation Trp464Lys)
560a.a.
p24
232 a.a.
p17
132 a.a.
Nef
206 a.a.
hinge
2 a.a.
hinge
2 a.a.
hinge
2 a.a.
Editor's Notes
Ongoing Phase IIb : The only HIV vaccine candidate currently being assessed for efficacy is the DNA + Ad5 vaccine from the NIH. Enrollment in the 2200 person trial has been relatively slow, with approximately 1850 of the 2200 enrolled since 2009. It is now expected that data from this trial will be available in late 2013. Next Phase IIb : Phase IIb trials repeating the RV-144 regimen will likely begin in 2014-2015.
There has been encouraging data suggesting that A combination of several epitope would probably be used to provide maximum coverage and target as many viruses as possible. We know from the current bNABS isolated that a combination of 2 of them could be sufficient to block over 99% of the virus tested.
When discussing vaccine that elicit cellular immunity one has to look at the shift in perspective in the field
Replicating vectors would allow a more sustained exposure of the immune system to the HIV antigen, allowing a stronger, longer lasting immune response the be induced.
CSF is a gate funded program where IAVI provides support, expertise and skills to help move product to development. We provide helps for investirgators which don ’ t have the experience, know how on how to move their product into development.