72157798 true A Phase Ia randomised double-blinded placebo-controlled study of a Bundibugyo virus disease vaccine, ChAdOx1 Ebola BDBV Vaccine (Recombinant), in healthy volunteers aged 18–55 years in the UK BD-Ebov-01 Primary Objective: To assess the safety and tolerability profile of a single dose of ChAdOx1 Ebola BDBV Vaccine (Recombinant) in healthy volunteers Secondary Objective: To assess the immunogenicity of a single dose of ChAdOx1 Ebola BDBV Vaccine (Recombinant) in healthy volunteers Background and study aims On 17th May 2026, the World Health Organisation declared a public health emergency of international concern after cases of severe fever and death were detected in the Democratic Republic of the Congo (DRC). The emergency is being caused by Bundibugyo virus (BVD), which is a species of Ebola virus, and like all species of Ebola, it causes a severe and often fatal infection in humans. Normally carried by fruit bats, it can cross over into humans through contact with infected animals. Once this occurs, it can then spread from person to person through direct contact with infected body fluids. Unlike another species of Ebola (Zaire ebolavirus), there are no licensed vaccines or medications to protect against BDBV infection. It is therefore vital that we develop a safe and effective vaccine against Bundibugyo virus disease (BVD) as soon as possible. Who can participate? Volunteers aged between 18 and 55 years old and in good health What does the study involve? The first 10 participants to be enrolled will all get a single dose of the vaccine. The next 40 participants will either receive a single dose of the vaccine or a saltwater placebo – neither they nor the study team will know which they have received until the end of the study. In addition, the first 10 participants to be enrolled will get a booster dose of the vaccine 6 months after the first dose. All participants will be followed up for a year and will attend a number of visits where safety can be checked and blood tests taken. The main purpose of this study is to assess the safety and tolerability of the study vaccine (ChAdOx1 Ebola BDBV Vaccine [Recombinant]), meaning researchers will carefully monitor any side effects, symptoms or changes in health that occur after vaccination and determine how well participants tolerate the vaccine. What are the possible benefits and risks of participating? The recruitment population will not directly benefit from participation in the study, as the clinical efficacy of the ChAdOx1 Ebola BDBV Vaccine (Recombinant) has not been established and will not be established by this study. Participants will be informed that they should not anticipate any protection from potential future BDBV infection following participation in this study. No specific additional medical care will be provided through participation, and medical procedures are performed with the aim of determining eligibility and safety during the trial. Specific risks related to the ChAdOx1 Ebola BDBV Vaccine (Recombinant): The most likely side effects that recipients of the ChAdOx1 Ebola BDBV Vaccine (Recombinant) may experience are short-lived local reactions (primarily injection site tenderness or pain) and systemic reactions (fatigue, headache, malaise, and feverishness) that resolve completely within days. Very rare serious reactions have been identified as part of post-marketing surveillance of ChAdOx1 nCoV-19 (Oxford/AstraZeneca COVID-19 vaccine). These include vaccine-induced thrombocytopenia and thrombosis (VITT), immune thrombocytopenic purpura, Guillain-Barré syndrome, transverse myelitis, capillary leak syndrome and anaphylaxis. It is currently unknown whether these very rare reactions occur with other ChAdOx vaccines. As the ChAdOx1 Ebola BDBV Vaccine (Recombinant) is similar to ChAdOx1 nCoV-19, participants will be informed about these conditions as part of the informed consent process for the trial. Investigators will be aware of potential signs of these conditions. Given existing safety data which supports the use of ChAdOx1 nCoV-19 in pregnant women, there is no reason to believe the ChAdOx1 Ebola BDBV Vaccine (Recombinant) would be harmful to women or the foetus during pregnancy. However, as yet there are no data on the use of the ChAdOx1 Ebola BDBV Vaccine (Recombinant) in pregnancy. Therefore, pregnant women will be excluded from the trial, and women of childbearing potential will be required to use highly effective contraception to take part. Other trial-related risks: Blood sampling during the trial may cause slight pain, bruising, light-headedness or fainting. The volume of blood given in the trial is less than that taken by regular blood donors over the same period, so it should not compromise healthy participants. Intramuscular injections carry a risk of bleeding in patients with very low platelet counts or coagulopathies. A baseline full blood count (with a platelet count) taken prior to vaccination would allow exclusion of volunteers with this risk. Where is the study run from? Oxford Vaccine Group, Churchill Hospital (UK) When is the study starting and how long is it expected to run for? July 2026 to December 2027 Who is funding the study? The Coalition for Epidemic Preparedness Innovations (CEPI) Who is the main contact? info@ovg.ox.ac.uk Occurrence of solicited local and systemic reactogenicity signs and symptoms the electronic diary provided to participants for 7 days following vaccination Occurrence of unsolicited adverse events (AEs) self-report by participants in the eDiary up to 7 days following each vaccination, or collected visits up to 28 days following each vaccination Occurrence of abnormal safety laboratory measures the electronic clinical database for the duration of the study period Occurrence of serious adverse events (SAEs) and adverse events of special interest (AESIs) collection visits until the end of the study Ethics approval required London-Brent Research Ethics Committee

2 Redman Place Stratford

London United Kingdom E20 1JQ 26/LO/0481 10.1186/ISRCTN72157798 1014429 CPMS: 74638 1014429 74638 Interventional Randomized controlled trial Blinded (masking used) Placebo Single Prevention Not applicable 2027-12-31T00:00:00.000Z United Kingdom England Oxford Vaccine Group

Churchill Hospital, Annexe Reception, Centre for Clinical Vaccinology and Tropical Medicine

Oxford England OX3 7LE true 1. Adults aged between 18 and 55 years (inclusive) at the time of screening. 2. Medically healthy, such that according to investigator judgement, hospitalisation within the study period is not anticipated, and the participant appears likely to be able to remain a study participant through the end of protocol-specified follow-up. Planned elective procedures for pre-existing conditions are allowable. 3. Able to attend the scheduled visits and to comply with all study procedures, including internet access for the recording of electronic diary cards. 4. Willing and able to give informed consent for participation in the study. 5. Willing to allow confirmation of past medical history either through provision of or access to a medical record summary or other medical documentation or allowing investigators to obtain a copy of their medical history from their GP practice or access it via electronic patient records. 6. Willing to allow their GP and/or consultant, if appropriate, to be notified of participation in the study. 7. Willing to provide their national insurance number or passport number to be registered on The Over-Volunteering Prevention System (TOPS). 8. Agreement to refrain from blood donation during the study. 9. For participants of childbearing potential only: willing to use highly effective contraception for the duration of the study AND to have a pregnancy test on the days of screening and vaccination and at the final visit. The pregnancy tests taken prior to vaccination must be negative. Adult 18 Years 55 Years All 50 0 1. Receipt of an investigational product within 12 weeks prior to enrolment or planned within the trial period. 2. Participation in another research study, in which procedures performed could compromise the integrity of this study, such as exposure to a different study IMP or significant volumes of blood taken, or are planning to do so within the trial period. 3. History of previous confirmed or suspected filovirus infection. 4. History of travel within 42 days of enrolment, or planned travel within study period, to countries currently reporting filovirus outbreaks as declared by the WHO (e.g., the Democratic Republic of the Congo and Uganda) 5. Prior receipt of a vaccine targeting filoviruses, including licensed and investigational vaccines 6. Prior receipt of a ChAdOx1- or ChAdOx2-vectored vaccine 7. Administration of immunoglobulins and/or any blood products within 3 months preceding the planned administration of the vaccine candidate. 8. Any confirmed or suspected immunosuppressive or immunodeficient state, including HIV infection; asplenia; severe infection(s); receipt of immunosuppressive therapy such as anti-cancer chemotherapy or radiation therapy within the preceding 12 months; or long-term systemic corticosteroid therapy (including for more than 7 consecutive days within three months preceding the planned administration of the vaccine candidate). 9. History of anaphylaxis or severe reaction in relation to vaccination. 10. History of allergic disease or reactions likely to be exacerbated by any component of the vaccine, including hypersensitivity to the active substance or to any of the excipients of the IMP. 11. History of hereditary angioedema, acquired angioedema, or idiopathic angioedema. 12. History of cancer (except basal cell carcinoma of the skin and cervical carcinoma in situ). 13. History of any serious psychiatric condition likely to affect participation in the study. 14. Participants who are pregnant, breastfeeding or lactating or are planning pregnancy during the study. 15. History of a bleeding disorder (e.g., Factor deficiency, coagulopathy, or platelet disorder) or prior history of significant bleeding or bruising following IM injections or venepuncture. 16. History of confirmed major thrombotic event (including cerebral venous sinus thrombosis, deep vein thrombosis, pulmonary embolism); history of antiphospholipid syndrome; or history of heparin-induced thrombocytopenia. 17. History of capillary leak syndrome. 18. History of Guillian-Barre syndrome, transverse myelitis or other neuroinflammatory syndrome. 19. History of currently active autoimmune conditions of any severity requiring treatment or on-going medical follow 20. Moderate, severe and/or uncontrolled cardiovascular disease, respiratory disease, gastrointestinal disease, liver disease, renal disease, haematological, immunological, endocrine disorder, or neurological illness. Well-controlled comorbidities in a healthy participant are acceptable as judged by the Investigator. 21. Suspected or known current alcohol abuse, as per investigator’s discretion. 22. Suspected or known injecting drug use within the 5 years preceding enrolment. 23. Acute or chronic hepatitis B or hepatitis C infection. 24. Any clinically significant finding on screening that is either unlikely to resolve or does not resolve (for example, on repeat testing at the discretion of an Investigator) within the recruitment timeline of the study. 25. Any other significant disease, disorder or finding which may significantly increase the risk to the volunteer if included in the study, affect the ability of the volunteer to participate in the study, or impair interpretation of the study data. 26. Study staff or a partner or dependent child of study staff. 2026-07-20T00:00:00.000Z 2026-09-30T00:00:00.000Z Bundibugyo ebolavirus Infections and Infestations This is a first-in-human Phase Ia trial to assess the safety, tolerability, and immunogenicity of the ChAdOx1 Ebola BDBV Vaccine (Recombinant) in healthy volunteers aged 18-55 years. The trial will consist of two phases. In phase A, an initial open-label cohort (cohort 1) of 10 participants will all receive a single dose of the ChAdOx1 Ebola BDBV Vaccine (Recombinant). Cohort 1 will be followed by a participant-observer blinded cohort of 40 participants (cohort 2), randomised 3:1 to receive either a single dose of the ChAdOx1 Ebola BDBV Vaccine (Recombinant) or a saline placebo. In phase B, the 10 healthy volunteers from Cohort 1 of the main study will receive a booster dose of the ChAdOx1 Ebola BDBV Vaccine (Recombinant) at 6 months following prime vaccination to achieve exploratory trial objectives. Participants in cohort 1 will have a screening visit, two vaccination visits and nine in-person follow-up visits. Cohort 2 will have a screening visit, one vaccination visit and six in-person follow-up visits. Biological/Vaccine Phase I ChAdOx1 Ebola BDBV Vaccine (Recombinant) Not expected to be made available a88d0fa0-5867-4dc4-8e8d-d3949c05609b bb99b68e-8472-43a7-a276-fac686b62d82 2459f3d9-231c-4a9c-aec2-f4505e85c195 f0d26c9b-65d1-4510-b068-01f9ddd91bb2 No Reyna Sara Quintero Barceinas Public Scientific

Oxford Vaccine Group, Department of Paediatrics, Centre for Clinical Vaccinology and Tropical Medicine, Churchill Hospital, University of Oxford

Oxford United Kingdom OX3 7LE +44 (0)1865611400 sara.quinterobarceinas@paediatrics.ox.ac.uk Public Katrina Pollock Principal investigator

Oxford Vaccine Group, Department of Paediatrics, Centre for Clinical Vaccinology and Tropical Medicine, Churchill Hospital, University of Oxford

Oxford United Kingdom OX3 7LE +44 (0)1865611400 katrina.pollock@paediatrics.ox.ac.uk Public University of Oxford https://ror.org/052gg0110 Non-commercial Coalition for Epidemic Preparedness Innovations http://dx.doi.org/10.13039/100016302 13512597 true Seroprevalence of Marburg virus infection and other WHO-priority pathogens in Cameroon, Guinea, and Uganda SeroMARV The study’s main aim is to assess previous exposure to Marburg virus (MARV) Infection in the general population in three countries in Africa, determined by measuring circulating IgG antibodies. Also, to estimate MARV force of infection (FOI), which is a measure of the risk of infection/level of pathogen circulation that can be used to determine the burden of MARV infection and disease. Primary objectives: 1. To assess previous exposure to Marburg Virus (MARV) Infection in the general population in three African countries, determined by measuring circulating IgG antibodies. 2. To estimate MARV force of infection (FOI) in the three African countries. 3. To develop a platform for the implementation of seroprevalence of WHO priority pathogens in Africa Secondary objectives: 1. To characterize age-specific and gender-specific seroprevalence trends. 2. To determine risk factors associated with prior infection with MARV in the three African countries. 3. To assess host genetic factors, including single-nucleotide polymorphism (SNP) of candidate genes that could be associated with susceptibility/protection from infection with MARV and other outbreak-worthy pathogens. 4. To estimate the seroprevalence of other WHO priority filovirus pathogens, including Ebola virus (EBOV), Sudan virus (SUDV), Bundibugyo virus (BDBV , and Taï Forest virus (TAFV), Ravn virus (RAVN) etc. Background and study aims Infectious diseases affect millions of people around the world every year. Most cases are mild, but some people become very unwell. There is a great deal that we do not understand about existing infections, and new infectious diseases continue to appear. Marburg Virus Disease is a rare but serious health threat in Africa. This research study seeks to find out the proportion of people who may have been exposed at some point. This will help us gain important information in order to better understand the disease so we can try to find better ways to manage and treat this infection in the future. Who can participate? Individuals aged 10 years and above who have lived in selected households for more than 3 months before the study began are eligible to participate. Households are chosen randomly within selected communities using population maps and GPS. Participation is entirely voluntary, and choosing not to take part will not affect you in any way. What does the study involve? If participants agree to take part, their basic information will be collected including their health and household. This includes details such as your age, sex, medical and travel history, exposure to infections, and household living conditions. A small blood volume sample (about 10 ml or two teaspoons) will be drawn to test for antibodies against Marburg virus and the other WHO-priority pathogens. The entire visit will take about 15 minutes. Data and samples will be handled confidentially and stored securely. Personal information will be coded and only used by authorized research staff. With participants’ permission, part of their samples will be stored for future approved research. What are the possible benefits and risks of participating? Participants may not receive direct personal benefits from participating but will be given feedback on their antibody test results, which can show if they have been exposed to the virus before. The study’s findings may help improve understanding of the infection and support future public health efforts. There are minimal risks involved. Drawing blood may cause slight pain or discomfort, but this will be done by trained professionals to reduce any discomfort. All participants’ information will be kept anonymous and confidential. Where is the study run from? The study is coordinated by the ALERRT consortium through the Global Health and Infectious Diseases Research Group at the Kumasi Centre for Collaborative Research in Tropical Medicine (KCCR) in Kumasi, Ghana, in collaboration with partner institutions in each participating country: 1. The University of Yaoundé 1, Biotechnology Center in Cameroon 2. The Centre of Excellence for the Prevention and Control of Transmissible Diseases (CEA-PCMT), University of Conakry (UGANC) in Guinea 3. The Uganda Virus Research Institute in Uganda. When is the study starting, and how long is it expected to run for? July 2025 to December 2025 Who is funding the study? The study is funded through the African coaLition for Epidemic Research, Response and Training (ALERRT) Consortium and the European and Developing Countries Clinical Trials Partnership Who is the main contact? Prof. John Humphrey Amuasi, amuas001@umn.edu Determination of MARV-specific IgG antibodies measured using Luminex Magpix -based multiplex immunoassay from plasma samples collected during participant enrolment 1. Quantitative levels of pathogen-specific IgG antibodies against selected candidate WHO-priority pathogens, measured using Luminex Magpix -based multiplex immunoassay from plasma samples collected during participant enrolment 2. Correlation of antibody titers with potential exposure histories or risk factors, assessed using questionnaire-derived demographic and exposure data collected during participant enrolment. Ethics approval required Comité Régional d'Ethique de la recherche en Santé Humaine du Sud (CRERSH SUD)

8 Rue 3038 quartier du Lac (Yaoundé III)

Ebolowa Cameroon 237 05/CRERSH SUD/SE/2025 Comité National d'Ethique de la Recherche en Santé (CNERS)

Conakry

Conakry Guinea 224 108/CNERS/25 Uganda National Council for Science and Technology

Plot 6, Kimera Road, Ntinda, PO Box 6884

Kampala United Arab Emirates 256 HS6241ES 10.1186/ISRCTN13512597 Multicenter population-based household cross-sectional survey employing a two-stage sampling approach Observational Cross sectional study Screening 2025-12-18T00:00:00.000Z Cameroon Guinea Uganda Centre de Biotechnologie, Université de Yaoundé 1 CAMEROUN

Université de Yaoundé 1, PO Box 337

Yaoundé Cameroon 237 Uganda Virus Research Institute

Plot No: 51 -59 Nakiwogo Road

Entebbe Uganda 256 Centre d’Excellence d’Afrique pour la Prévention et le Contrôle des Maladies Transmissibles (CEA-PCMT)

University of Conakry (UGANC) Campus Hadja Mafory Rue Dixinn 261, Route de Donka BP : 1017

Conakry Guinea 224 Population 1. Individuals aged 10 years and above 2. Member of the visited household 3. Resides in household for more than 3 months before study start 4. Willingness to participate in the study demonstrated by a signed or thumbprinted informed consent or assent form Mixed 10 Years 100 Years All 2116 3013 Known pathology or a health problem contraindicated with blood sample collection 2025-07-02T00:00:00.000Z 2025-12-18T00:00:00.000Z Marburg virus infection Infections and Infestations This is a household-based cross-sectional survey using a two-stage sampling method. First, communities are conveniently selected and divided into clusters using population data. GPS coordinates are randomly generated in clusters, guiding selection of nearby households. From each household, one individual is chosen based on age and gender distribution; some homes provide multiple participants. The approach ensures representative sampling and enables infection rate and transmission estimates. If participants agree to take part, their basic information will be collected including their health and household. This includes details such as your age, sex, medical and travel history, exposure to infections, and household living conditions. A small blood volume sample (about 10 ml or two teaspoons) will be drawn to test for antibodies against Marburg virus and the other WHO-priority pathogens. The entire visit will take about 15 minutes. Data and samples will be handled confidentially and stored securely. Personal information will be coded and only used by authorized research staff. With participants’ permission, part of their samples will be stored for future approved research. Other Data sharing for the SeroMARV study will follow the ALERRT Master Data Management Plan. Participant-level data will be made available for sharing within 1 and 2 years upon study completion, in line with the EDCTP Data Sharing Policy, FAIR principles (ensuring data are Findable, Accessible, Interoperable, and Reusable), and the PANDORA/ALERRT Data Sharing Principles emphasizing Fairness, Ethics, Equity, Quality, Usability, Transparency, and Timeliness. The SeroMARV data will be anonymized and accompanied by metadata and documentation, including the study protocol, and codebook with the data dictionary. Data sharing will be coordinated by the lead data management team and require approval from the Lead Principal Investigator to share the data with the Health Research Data West Africa platform. Available on request 73fc3917-b47a-44b7-9b2e-c292c975918c 4a3688cb-4acf-4d9c-a05e-441fec89a965 b2c28ad4-71e5-480e-95c3-706e868c9740 efa6d9ea-3fb7-4453-a7c0-06c8a4989fac ef8aff72-bdbe-4691-af9d-17d94757756b 15a804c5-538a-4914-8cb3-dd1c55213e9c Yes John Humphrey Amuasi https://orcid.org/0000-0002-8640-2662 Principal investigator

Kumasi Centre for Collaborative Research in Tropical Medicine South-end Asuogya Road KNUST

Kumasi Ghana 233 +233 (0)20 6300405 amuas001@umn.edu Public Anthony Afum-Adjei Awuah https://orcid.org/0000-0002-8912-9673 Scientific

Kumasi Centre for Collaborative Research in Tropical Medicine South-end Asuogya Road KNUST

Kumasi Ghana 233 +233 (0)24 210 7721 afumadjeiawuah@kccr.de Public Alexander Owusu Boakye https://orcid.org/0009-0006-1559-7673 Public

Kumasi Centre for Collaborative Research in Tropical Medicine South-end Asuogya Road KNUST

Kumasi Ghana 233 +233 (0)56 174 1866 a.boakye@kccr.de Public Kumasi Centre for Collaborative Research in Tropical Medicine Research organisation https://ror.org/032d9sg77 Non-commercial European and Developing Countries Clinical Trials Partnership http://dx.doi.org/10.13039/501100001713 African coaLition for Epidemic Research, Response and Training (ALERRT)