Developing Vaccines for Neglected Diseases
Vaccine Technologies II Albufeira, Portugal June 5th, 2008
Douglas Holtzman, Ph.D., M.P.H. Senior Program Officer, Global Health Program
Bill & Melinda Gates Foundation
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Three Programs, One Goal: Equity
US Program
» High school education » Public library internet access
Global Development
» Financial services for the poor (e.g. microfinance) » Agricultural productivity and markets
Global Health
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Perspective on Global Health
The vision:
To ensure that a child born in the developing world has the same chance for good health as a child born in the developed world
The goal:
Build on advances in science and technology to save lives, improve health, and reduce disease in the developing world
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Prioritization
Burden of disease Inequity of burden Lack of attention Possibility for impact
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Disease Areas
HIV (vaccines, microbicides, treatment, prevention, education) TB (drugs, vaccines, diagnostics) Malaria (drugs, vaccines, vector control, diagnostics, scale-up) Pneumonia Diarrhea Nutrition Maternal Health
Discover, develop and deliver
Kinetoplastids
innovative solutions
Helminths HPV Dengue/Japanese Encephalitis Polio
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Partnerships
Global Alliance for Vaccines and Immunization (GAVI) Global Fund for AIDS, TB and Malaria HIV Vaccine Enterprise Medicines for Malaria Venture (MMV) Malaria Vaccine Initiative (MVI) MACEPA PATH Vaccine Solutions (PVS) Aeras (TB Vaccines) Global Alliance for TB Drug Development (GATB) ACHAP Grand Challenges in Global Health IVI/PDVI Etc….
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PDP-Private Sector R&D Deals:
Win/Win Proposition?
PDP provides
• Financing
PDP gets
PDP
• LDC trial sites
• IP or low price in
• Access/distribution plans
LDCs
• Rapid access • Recognition as catalyst
Drugs and
Vaccines for
• Market analysis • Global health expertise
Joint
Neglected Diseases
R&D
Industry gets
• IP and pricing for rich countries
Industry provides
• Technology candidate • Related know-How:
-process engineering -GCP, GLP, QC/QA -scale up and manufacturing -project management
• Financing
• Essential financing for small biotech firms
• New technology platforms with other commercial uses
• Good will
Private
• Manufacturing capacity
Source: Adopted from MMV; Rockefeller Foundation
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THE GOAL
» To encourage scientific risk-taking on creative, unorthodox ideas for global health
THE INITIATIVE
» US$100 million funding initiative over 5 years » Will fund hundreds of projects based on two-page submission – next round opens September 15th
» Initial grants of $100,000 with potential for additional funding (~$1M) if promising
» Opportunity for direct engagement with the private sector
» Sign up at www.gcgh.org/explorations/ for email updates
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Pre-clinical research toward a vaccine against African trypanosomiasis
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Objectives
To identify specific candidate antigens that generate protective immune responses
against Trypanosoma brucei in cattle
To further test plant-based transient gene expression systems for production of vaccines appropriate for developing countries
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African Trypanosomiasis
Parasitic disease limited to tropical Africa 60M people at risk; affects all ages ~40-60K annual deaths – most die unreported in the bush (~300-500K?)
Resurgence of disease Billions of $ of lost agricultural productivity World’s greatest disparity disease
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Distribution of sleeping sickness in sub- Saharan Africa, 1999
WHO http://www.who.int/csr/resources/publications/CSR_ISR_2000_1tryps/en/index.html
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Cycle of disease
CNS Infection
Stage II
Infected fly bite
Systemic infection
Stage I
Death
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Antigenic shifts lead to….
VSG1 VSG2 VSGx
Time
….waves of parasitaemia
VSG = variable surface glycoprotein
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Proof of Principle
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Trypansome tubulin-rich regions as “Achilles Heel”
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Technology: Alfalfa Mosaic Virus
P1 P2
P3
CP
CP
Viral gene structure
Electron
F
Micrograph
P
- C
- K
D
P
- G
- A
- T
- I
- R
- L
S
Particle-based peptide delivery system
YS
M
Antigenic peptide
Slide provided by Dr. Yusibov, Fraunhofer CMB
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Mouse Experiments Show Protection
- Experiment #1
- Experiment #2
- Antigen used
- Protection rate (%)
- Vaccine candidate
- Protection rate (%)
Atub 1-4 Atub 5-8 Btub 1-4 Btub 5-8 AlMV
60 70 90 90
0
ALMV Atub 1-4
13 40 40 53
100 100
0
Atub 5-8 Btub 1-4 Btub 5-8
- Adjuvant
- 0
- Btub 2
Btub 3
- Btub 5
- 100
40 27 13 27 33
0
Btub 11
Tubulin (native)
Adjuvant
Atub (rec. full length) Btub (rec. full length)
Negative control
Slide provided by Dr. Yusibov, Fraunhofer CMB
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Parasitemia in cattle post challenge
with T. brucei brucei
Days post challenge
Groups AlMV
- cow
- -4
- 7
- 10
- 12
- 14
- 17
- 40
- 45
12341234
--------
++++++++
++++++++
+
- -
- -
- +
+++-
++++-
+++++++
+++-
+++-
Btub2+ Btub5
- -
- -
- -
- -
- -
- -
- -
- -
- -
- -
- -
- -
Slide provided by Dr. Yusibov, Fraunhofer CMB
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Survival of cattle post challenge with
T. brucei brucei
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