African Horse sickness control through

Baptiste DUNGU DVM PhD CEO Onderstepoort Biological Products Ltd. OBP Onderstepoort, Pretoria South Africa Layout

Onderstepoort OBP

AHS history

Vaccine in the control of AHS

Roadmap toward an effective safer DIVA AHS FVS OBP OVI Faculty of Veterinary Science

Onderstepoort Biological Products

Onderstepoort Veterinary Institute More than 50 different livestock and other biological products OBP…in short

State owned company: commercial mandate 200 staff member More than 50 different biologics:

 28 bacterial vaccines,  14 viral vaccines,  4 Protozoal (Blood) vaccines  Autogenous vaccines  6 diagnostic reagents  Therapeutic sera  Culture media Production Capacity: more than 150 million doses annually Species covered: Cattle, Sheep, Goat, equine, poultry “What we wish to point out is that, as a scourge which annually causes immense loss to the Colonies, it behoves the authorities to take adequate and scientific means to combat it. As yet absolutely nothing is known about its etiology…it is manifest that until the cause is known we cannot hope to battle with the . The discovery of the haematozoon of tsetse-fly disease was a notable feather in the cap of the school of research at Cambridge. Cannot some pathologist from the most progressive of Universities help us in like manner with the paarde-ziekte when peace once more reigns from Cape Town to the Zambezi? (Anon., 1900). “

6 7 | Onderstepoort Biological Products © | March 9, 2020 …are we running in circles?

www.goldcircle.co.za Summerveld Training Centre at Shongweni. By 1915 • •Inoculable but not contagious •Transmitted by blood sucking insects (mentions but suspects ) •Has to be a •Horses, dogs once recovered not viraemic •Prevention and cure •Identifies immunity as potentially the best option •Did first using serum of recovered horse/mule with virus •Multiple serotypes “antigenic plurality”, some cross protection between certain types

9

Vaccine breakthrough, the 60 year project

AHS historical distribution

Egypt (1928, 1943, 1953, 1958, 1971), Palestine, Jordan, Lebanon, Syria (1944) Iran and Persian Gulf (1959-1961) Libya, Tunisia, , Algeria (1965-1967) Saudi Arabia (1989, 1997) Spain and southern Iberian Peninsula (1965-66, 1987-1991) Cape Verde Islands (1999)

M Quan, 2014 AHS – THE DISEASE

• -borne infection () of equidae, in large parts of Africa • 9 different serotypes with some cross-neutralization • Notifiable disease, OIE Status; worldwide importance

• Exceptional mortality rate in naïve horses • Up to 95% in horses and 50-70% in mules • Equus burchelli believed to be primary viral reservoir • Transmission primarily by biting midges of the genus Culicoides • Extent of favourable climatic conditions for breeding of Culicoides • Most serious outbreaks often during March and April

• C. imicola: 98% of all species in trap catches at Onderstepoort and AHSV repeatedly isolated • C.bolitinos: implicated as vector in a number of outbreaks AHS - SUSCEPTIBILITY

Equids - Horses Resistant Mules Donkeys 10% Canines 50-70%

70-95%

Susceptible African horsesickness virus 10 proteins 10 dsRNA Outer capsid pro- genes VP1 teins VP5 & VP2 1

VP2 2 VP3 3

4 VP4 5 VP5 6 NS1

7 NS2 8 VP6 9 VP7 Core protein VP7 Minor core proteins 10 NS3 Why is AHS still a problem?

• The virus and vectors are endemic in SA & large parts of Africa • Inadequate immunity • No sustained vaccination • Wrong advice and wrong use of vaccine • Uncontrolled movement of horses • Weaknesses in surveillance AHS Control in South Africa Surveillance, Vaccination and Movement control

Due to nature of current AHS LAV, vaccination restricted to low vector seasons With a non-replicating vaccine, the vaccination program could be modified in allowing more flexibility on time and animals to be vaccinated The virus is endemic in SA

AHSV PCR submissions 2017+18

Total: 776

Positive 2017: 137/363 2018: 123/413 Serotypes per season

35

30

25

20

15

10

5

0 1 2 3 4 5 6 7 8 9

2016 - 2017 2017 - 2018 AHS-attenuated live virus (ALV) Vaccine since 1994

AHS Bottle I AHS Bottle II Cross reaction Serotype 1 Serotype 2 1 ↔ 2 Serotype 3 Serotype 6 3 ↔ 7 Serotype 4 Serotype 7 4 Serotype 8 5 ↔ 8 6 ↔ 9

• Exclude serotype T5 and T9 • T5 was omitted as vaccinated foals suffered severe reactions and death. Follow-up vaccination studies showed that the combination of T4 and T5 in bottle I was the cause. • T9 is low-immunogenic and was rare in southern Africa until recently AHS ALV vaccine challenges

Risk of reassortment Not in pregnant animals Restricted for low vector periods Not recommended in high vector periods or during outbreaks No DIVA May not be suitable for epizootic situations or free countries Vaccination may be considered as an “infection” (OIE status) Vaccine produced in Senegal for example comprises all 9 serotypes…

AHS free

AHS endemic

AHS vaccine manufacturer New vaccine? Why? Current vaccine Attribute Comply Protection to all serotypes  > 90% animals protected  Duration of immunity ≥ 1 year  Safety ? Storage, transport temperature 4°C  Enzootic & epizootic use × Marker vaccine (DIVA) × Traditional vaccine • Live attenuated technologies: • Inactivated vaccines

• Live Disabled Single Infection Cycle (DISC) AHS vaccine vaccines: (VP6-deficient AHSV strains) New technologies • Live Disabled Single Animal (DISA) vaccines (based on (NS3/NS3a-deficient AHSV strains) technologies • Inactivated (capsid swap) vaccines Technology • Sub-unit adjuvanted vaccines to date Review report by • Canarypox virus expressing AHSV-VP2 and J. Castillo): AHSV-VP5 • Modified Vaccinia Ankara (MVA) expressing AHSV-VP2

Other • Plant expressed AHS-VLP expressed in plant (University of technologies Cape Town, funded by DST) IHSC driven process for the Glossary of terms Executive Summary development of a DIVA AHS Background to the Process Approach used vaccine Roadmap toward the development of a DIVA AHS vaccine Desired Characteristics for the DIVA AHS vaccine Target Product Profile (TPP) AHS vaccine technology review Vaccination strategy overview Market and economic aspects review Stakeholders inputs & key partnerships for AHS DIVA vaccine development Candidate vaccines selection for the medium term Inactivated AHS vaccines Canarypox vaccine candidate MVA-VP2 vaccine Plant expressed AHS VLP vaccines Critical activities for the development of the AHS DIVA vaccine Approved experimental vector-proof horse stables Challenge model and studies Timelines for the development of the selected candidate Funding and funding models Partial funding (pump-priming) Funding of specific candidates Legal and regulatory needs Recommendations for the Way forwards beyond the present process • Profile of the most desirable characteristics: out of TPP • Protection to all 9 serotypes • DIVA • Flexible for use as monovalent in case of defined outbreaks or epidemics • Flexible for use in different combinations based on specific epidemiological situation (2 to 3 serotypes in certain regions) • Effective on all equids and possibly all susceptible animals (e.g. camels) • Safe for use in horses of all ages and all physiological stages (pregnant, young etc.) • Adaptable to different vaccination programs: high performance, working horses, movement of horses to and from endemic regions, emergency vaccination etc. • Affordable to different types of equids

Most important desired characteristics Attribute Minimum Ideal 1 Antigen immunogens protective to AHSV infection Immunogens protective to all 9 serotypes of AHSV Detailed 2 Indication for use For active immunisation of horses against For active immunisation of equids (incl. mules and donkeys) of AHSV all ages and physiological conditions against all 9 serotypes of desired AHS AHSV. Suitable for immunization of wild equids DIVA vaccine Epidemiological relevance Suitable for protection of horses in AHS Suitable for protection of equids in enzootic and epizootic enzootic regions regions, including immunisation of equids being moved between characteristics: regions of different AHS status EFFICACY Expected efficacy To prevent disease in > 70% of vaccinated To prevent infection in > 80% of vaccinated animals Target Product animals Immunity spectrum Protection to all 9 serotypes Equal protection to all 9 serotypes with possibility of individual Profiles serotype protection 5 Onset of immunity Within 3 weeks of complete vaccination Within 10 days following complete vaccination

6 Route of administration Subcutaneous (SC) or Intramuscular (IM) Intramuscular 7 Regimen - vaccination Yearly vaccination to include primo and Yearly vaccination to include primo and booster doses booster doses 8 Recommended age at first vaccination As early as possible

9 Duration of immunity Minimum of 12 months Protection to all serotype for at least one year SAFETY 10 Expected safety Mild and transient injection site reactions Mild and transient injection site reactions and pyrexia lasting and pyrexia lasting less than 14 days in up to less than 7 days in up to 10% of vaccinated animals. 20% of vaccinated animals. 11 Reproductive safety No for milk, 4 weeks for meat Suitable for all stages of pregnancy Suitable for stallions at any stage 12 Environmental safety No vaccine derived infectious material detectable… 14 Reassortment risk Demonstrated inability to reassort with Structurally incapable of reassorting with other wildtype AHSV DIVA 15 Detection of infection Detection of infection in vaccinated animals Detection of infection in vaccinated animals by PCR or serology by PCR or serology OTHER VACCINE CHARACTERISTICS 16 Package size 1 to 10 doses 1 and 10 doses 17 Cost to end users Not more than current vaccines Not more than double current vaccine price 18 Storage requirements Stable at 4°C Stable at 30°C for 48 hours 19 Shelf-life as packaged for sale 12 months 24 months Selection of AHS vaccine technology

Inactivated AHS vaccine • More appropriate for medium term solution • Proven efficacy & safety • Proven polyvalency • DIVA possible: PCR & ELISA (including purified vaccine) • No risk of virus maintenance • Industrial processes available • Interest expressed by manufacturers • If used largely, may contribute to reducing endemicity • Suitable for use during outbreaks in all age and physiological groups

Inactivated AHS vaccine development currently ongoing Development of the inactivated AHS vaccine at OBP

• Vaccine development

• Establishment of a Vector protected facility for clinical studies

• Development and validation of DIVA diagnostic assays

• Interaction with partners (scientific, technical, stakeholders, funders) Progress with inactivated AHS vaccine development

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33

Jul-19 Jul-20 Jul-21

Jan-20 Jan-21

Jun-19 Jun-20 Jun-21

Oct-19 Oct-20 Oct-21

Apr-19 Sep-19 Feb-20 Apr-20 Sep-20 Feb-21 Apr-21 Sep-21

Dec-19 Dec-20

Aug-19 Nov-19 Aug-20 Nov-20 Aug-21 Nov-21

Mar-19 Mar-20 Mar-21

May-19 May-20 May-21 Refurbishment of vector-proof stables in compliance with Vet services requirements Refurbishment of OBP vector protected stables √ √ √ √ √ √ √ Multivalent Inactivated AHS vaccine project plan Proof of concept (PoC) 9 AHSV serotypes ID confirmation √ √ Agreements between partners finalised √ √ √ Production of MS √ √ √ Production of 9 virus antigens √ √ √ √ Assessment of Inactivation & concentration √ √ Formulation of mono- & multivalent vaccines Immunogenicity study in horses PoC for multivalent immunogenicity Challenge studies in horses PoC for multivalent protection Full development Production of GMP seed material √ Prodution of pilot batches Dose titration studies in horses Development & validation of QC procedures √ Production of industrial batches Product Shelflife Full regulatory safety study in horses Regulatory efficacy studies in horses Duration of immunity Field safety and Efficacy Registration Dossier preparation & submission Agreement OBP-HKJC

HKJC has granted OBP GBP100,000 as contribution toward the development of the inact AHS vaccine

Funding to be used toward the Immunogenicity in horses Proof of Concept clinical study Vector-protected animal facility

Facility required by DAFF for vector-born animal clinical studies

Required for immunogenicity, challenge and other regulatory clinical studies

Currently being established at OBP DIVA Diagnostics • ELISA format • Based on ratio of anti-NS3 vs anti-VP7 antibodies • NS3 varies between serotypes • Determine minimum NS3 antigens to react with anti- NS3 antibodies of all serotypes • Validation • Determine analytical sensitivity and specificity • Establish diagnostic specificity

• RT-PCR • Targeting any serogroup specific gene • e.g. Segment 7 Way forward…

• South African African horse sickness vaccine working group (SA AHS VWG) established since 28th June 2019 • Some of the major activities: • Review of the TPP for AHS vaccines • Draft guidelines for selection of seed strains for AHS vaccines • Draft guidelines for multivalent immunogenicity studies in horses • Standards for the design and operation of vector protected facilities for the keeping of animals for experimental infections with vector-borne animal pathogens • Fundraising… THANK YOU