September 2021
Safety and long-term immunogenicity of the two-dose heterologous Ad26.ZEBOV and MVA-BN-Filo Ebola vaccine regimen in adults in Sierra Leone: a combined open-label, non-randomised stage 1, and a randomised, double-blind, controlled stage 2 trial
The Ebola epidemics in west Africa and the Democratic Republic of the Congo highlight an urgent need for safe and effective vaccines to prevent Ebola virus disease. This study aimed to assess the safety and long-term immunogenicity of a two-dose heterologous Ad26.ZEBOV and MVA-BN-Filo Ebola vaccine regimen in Sierra Leone, a country previously affected by Ebola.
The study showed that the vaccine regimen was well tolerated and immunogenic, with persistent humoral immune responses, suggesting suitability of this regimen for Ebola virus disease prevention in adults.
Publication: David Ishola, Daniela Manno et al. (September 2021). Safety and long-term immunogenicity of the two-dose heterologous Ad26.ZEBOV and MVA-BN-Filo Ebola vaccine regimen in adults in Sierra Leone: a combined open-label, non-randomised stage 1, and a randomised, double-blind, controlled stage 2 trial. Lancet Infectious Diseases. https://doi.org/10.1016/S1473-3099(21)00125-0
September 2021
Safety and immunogenicity of the two-dose heterologous Ad26.ZEBOV and MVA-BN-Filo Ebola vaccine regimen in children in Sierra Leone: a randomised, double-blind, controlled trial
Children account for a substantial proportion of cases and deaths from Ebola virus disease. This study aimed to assess the safety and immunogenicity of a two-dose heterologous Ad26.ZEBOV and MVA-BN-Filo Ebola vaccine regimen in a paediatric population in Sierra Leone.
The study showed that the vaccine regimen was well tolerated with no safety concerns in children aged 1–17 years, and produced a strong immune response, suggesting suitability of this regimen for Ebola virus disease prevention in children.
Publication: Muhammed Afolabi et al. (September 2021). Safety and immunogenicity of the two-dose heterologous Ad26.ZEBOV and MVA-BN-Filo Ebola vaccine regimen in children in Sierra Leone: a randomised, double-blind, controlled trial. Lancet Infectious Diseases. https://doi.org/10.1016/S1473-3099(21)00128-6
August 2021
Use of Iris Scanning for Biometric Recognition of Healthy Adults Participating in an Ebola Vaccine Trial in the Democratic Republic of the Congo: Mixed Methods Study
A partnership between the University of Antwerp and the University of Kinshasa implemented the EBOVAC3 clinical trial with an Ebola vaccine regimen administered to health care provider participants in Tshuapa Province, Democratic Republic of the Congo. The clinical trial used iris scan technology to identify all health care provider participants enrolled in the vaccine trial, to ensure that the right participant received the right vaccine at the right visit.
This study aimed to assess the acceptability, accuracy, and feasibility of iris scan technology as an identification method within a population of health care provider participants in a vaccine trial in a remote setting. It found that iris scans are highly acceptable as an identification tool in this context and provide a high level of accuracy that can reliably identify individuals.
Publication: Zola Matuvanga T, Johnson G, Larivière Y, Esanga Longomo E, Matangila J, Maketa V, Lapika B, Mitashi P, Mc Kenna P, De Bie J, Van Geertruyden JP, Van Damme P, Muhindo Mavoko H. (August 2021). Use of Iris Scanning for Biometric Recognition of Healthy Adults Participating in an Ebola Vaccine Trial in the Democratic Republic of the Congo: Mixed Methods Study. J Med Internet Res. 23(8):e28573. doi: 10.2196/28573
June 2021
Algorithm for the support of non-related (serious) adverse events in an Ebola vaccine trial in the Democratic Republic of the Congo
Implementing an Ebola vaccine trial in a remote area in the Democratic Republic of the Congo (DRC), and being confronted with a dysfunctional health care system and acute unmet health needs of participants, ethical considerations were made regarding the ancillary care obligations of the sponsor and researchers. Spurred by the occurrence of non-related (serious) adverse events, the Universities of Antwerp and Kinshasa jointly developed an algorithm and related policy, which will be implemented in November 2021.
Publication: Lemey G, Larivière Y, Zola TM, et al. (June 2021). Algorithm for the support of non-related (serious) adverse events in an Ebola vaccine trial in the Democratic Republic of Congo. BMJ Global Health. 6(6). doi:10.1136/bmjgh-2021-005726
December 2020
Nonhuman primate to human immunobridging to infer the protective effect of an Ebola virus vaccine candidate
It has been proven challenging to conduct traditional efficacy trials for Ebola virus (EBOV) vaccines. In the absence of efficacy data, immunobridging is an approach to infer the likelihood of a vaccine protective effect, by translating vaccine immunogenicity in humans to a protective effect, using the relationship between vaccine immunogenicity and the desired outcome in a suitable animal model. The authors of this study propose to infer the protective effect of the Ad26.ZEBOV, MVA-BN-Filo vaccine regimen with an 8-week interval in humans by immunobridging.
The study finds that, based on the immunobridging analysis, the EBOV GP-specific-binding antibody levels elicited by the Ad26.ZEBOV, MVA-BN-Filo vaccine regimen in humans will likely provide protection against EBOV disease.
Publication: Roozendaal R, Hendriks J, van Effelterre T, et al. (December 2020). Nonhuman primate to human immunobridging to infer the protective effect of an Ebola virus vaccine candidate. NPJ Vaccines. 5(1), 112. https://doi.org/10.1038/s41541-020-00261-9
November 2020
Comparative ethnographies of medical research: materiality, social relations, citizenship and hope in Tanzania and Sierra Leone
This paper by the EBOVAC Social Science team brings together ethnographic research carried out during two clinical prevention trials as part of the EBOVAC-Salone study to explore identities, relations and political imaginations that were brought to life by these different technologies. It highlights the ways in which critical anthropological engagement in clinical trials can help us radically reconsider the parameters and standards of medical research.
Publication: Enria L, Lees S. (November 2020). Comparative ethnographies of medical research: materiality, social relations, citizenship and hope in Tanzania and Sierra Leone. Int Health. 12(6), 575-583. https://doi.org/10.1093/inthealth/ihaa071
October 2020
Implementation of accelerated research: strategies for implementation as applied in a phase 1 Ad26.ZEBOV, MVA-BN-Filo two-dose Ebola vaccine clinical trial in Uganda
The 2013–2016 Ebola epidemic in West Africa is the worst ever caused by Ebolaviruses with over 28,000 human cases and 11,325 deaths. The World Health Organisation (WHO) declared the epidemic a public health crisis that required accelerated development of novel interventions including vaccines. The Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit (MRC/UVRI & LSHTM Uganda Research Unit) was among the African research sites that implemented the VAC52150EBL1004 Ebola vaccine trial.
This paper reports on the strategies utilised by the Unit and sponsor in ensuring expedited clinical trial approval and accelerated conduct.
Publication: Kitonsa J, Ggayi AB, Anywaine Z, et al. (October 2020). Implementation of accelerated research: strategies for implementation as applied in a phase 1 Ad26.ZEBOV, MVA-BN-Filo two-dose Ebola vaccine clinical trial in Uganda. Glob Health Action. 13(1), 1829829. https://doi.org/10.1080/16549716.2020.1829829
June 2019
Dynamics of the humoral immune response to a prime-boost Ebola vaccine: quantification and sources of variation
The Ebola vaccine based on Ad26.ZEBOV/MVA-BN-Filo prime-boost regimens is being evaluated in multiple clinical trials. The long-term immune response to the vaccine is unknown, including factors associated with the response and variability around the response. This study analysed data from three phase 1 trials performed by the EBOVAC1 Consortium in four countries: the United Kingdom, Kenya, Tanzania, and Uganda.
Publication: Chloé Pasin, Irene Balelli, Thierry Van Effelterre, Viki Bockstal, Laura Solforosi, Mélanie Prague, Macaya Douoguih, Rodolphe Thiébaut, for the EBOVAC1 Consortium. (June 2019). Dynamics of the humoral immune response to a prime-boost Ebola vaccine: quantification and sources of variation. Journal of Virology. 93 (18). https://doi.org/10.1128/JVI.00579-19
April 2019
Determinants of Transmission Risk During the Late Stage of the West African Ebola Epidemic
Understanding risk factors for Ebola transmission is key for effective prediction and design of interventions. This EBOVAC modelling study used data on 860 cases in 129 chains of transmission from the latter half of the 2013–2016 Ebola epidemic in Guinea. Using negative binomial regression, the study determined characteristics associated with the number of secondary cases resulting from each infected individual. The analysis highlights the key role that age, receiving treatment, and safe burial played in the spread of EVD.
Publication: Alexis Robert, W John Edmunds, Conall H Watson, Ana Maria Henao-Restrepo, Pierre-Stéphane Gsell, Elizabeth Williamson, Ira M Longini, Jr. Keïta Sakoba, Adam J Kucharski, Alhassane Touré, Sévérine Danmadji Nadlaou, Boubacar Diallo, Mamamdou Saidou, Barry Thierno, Oumar Fofana, Louceny Camara, Ibrahima Lansana, Kaba Lansana, Sylla Mohamed, Lamine Diaby, Ousmane Soumah, Abdourahime Diallo, Amadou Niare, Abdourahmane Diallo, Rosalind M Eggo. (April 2019). Determinants of Transmission Risk During the Late Stage of the West African Ebola Epidemic. American Journal of Epidemiology. 188 (7), 1319-1327. https://doi.org/10.1093/aje/kwz090
March 2019
Control of Ebola virus disease outbreaks: comparison of health care worker-targeted and community vaccination strategies
Health care workers (HCW) are at risk of infection during Ebola virus disease outbreaks and therefore may be targeted for vaccination before or during outbreaks. The effect of these strategies depends on the role of HCW in transmission which is understudied. To evaluate the effect of HCW-targeted or community vaccination strategies, this EBOVAC modelling study used a transmission model to explore the relative contribution of HCW and the community to transmission.
Publication: Robert A, Camacho A, Edmunds WJ, Baguelin M, Muyembe J, Rosello A, Keita S, Eggo R. (March 2019). Control of Ebola virus disease outbreaks: comparison of health care worker-targeted and community vaccination strategies. Epidemics. ISSN 1755-4365. https://doi.org/10.1016/j.epidem.2019.03.001
February 2019
Safety and Immunogenicity of a 2-Dose Heterologous Vaccine Regimen With Ad26.ZEBOV and MVA-BN-Filo Ebola Vaccines: 12-Month Data From A Phase 1 Randomized Clinical Trial in Uganda and Tanzania
This phase 1 study assessed safety, tolerability, and immunogenicity of heterologous two-dose Ad26.ZEBOV, MVA-BN-Filo vaccination regimens in the Lake Victoria Basin of Tanzania and Uganda in mid-level altitude, malaria-endemic settings. The study showed that this vaccine regimen is well tolerated and immunogenic in healthy volunteers (aged 18-50 years).
Publication: AnywaineZ, Whitworth H, Kaleebu P, Praygod G, Shukarev G, Manno M, Kapiga S, Grosskurth H, Kalluvya S, Brockstal V, Anumendem D, Luhn K, Robinson C, Douoguih M, Watson-Jones D. (February 2019). Safety and Immunogenicity of a 2-Dose Heterologous Vaccine Regimen With Ad26.ZEBOV and MVA-BN-Filo Ebola Vaccines: 12-Month Data From A Phase 1 Randomized Clinical Trial in Uganda and Tanzania. The Journal of Infectious Diseases. https://doi.org/10.1093/infdis/jiz070.
February 2019
Safety and Immunogenicity of a 2-Dose Heterologous Vaccine Regimen With Ad26.ZEBOV and MVA-BN-Filo Ebola Vaccines: 12-Month Data From a Phase 1 Randomized Clinical Trial in Nairobi, Kenya
During the 2014 West African Ebola outbreak, Ebola vaccine development was accelerated. The phase 1 VAC52150EBL1003 study was performed to investigate 2-dose heterologous vaccination with Ad26.ZEBOV and MVA-BN-Filo in an African population located in a high-altitude setting in Nairobi, Kenya.
The study found that two-dose heterologous vaccination with Ad26.ZEBOV and MVA-BN-Filo was well tolerated and highly immunogenic against Ebola virus glycoprotein.
Publication: Mutua G, Anzala O, Luhn K, Robinson C, Bockstal V, Anumendem D, Douoguih M. (February 2019). Safety and Immunogenicity of a 2-Dose Heterologous Vaccine Regimen With Ad26.ZEBOV and MVA-BN-Filo Ebola Vaccines: 12-Month Data From a Phase 1 Randomized Clinical Trial in Nairobi, Kenya. The Journal of Infectious Diseases. 220(1), 57-67. https://doi.org/10.1093/infdis/jiz071
February 2019
Health care worker vaccination against Ebola: Vaccine acceptance and employment duration in Sierra Leone
Health care workers (HCW) are at high risk of Ebola virus disease (EVD) infection during epidemics and may contribute to onward transmission, and therefore HCW-targeted prophylactic vaccination strategies are being considered as interventions. To assess the feasibility of preventive HCW vaccination, the EBOVAC modelling team conducted a pilot survey on staff turnover and vaccine acceptance amongst 305 HCW in Freetown and Kambia districts of Sierra Leone.
The study found that vaccinating HCW against EVD could be feasible as employment appeared stable and vaccine acceptance high. However, even with high vaccine efficacy and long-lasting immunity, repeated campaigns or vaccination at employment start may be necessary to maintain high coverage.
Publication: Jendrossek M, Edmunds WJ, Rohan H, Clifford S, Mooney T, Eggo R. (February 2019). Health care worker vaccination against Ebola: Vaccine acceptance and employment duration in Sierra Leone. Vaccine. 37(8), 1101-1108. https://doi.org/10.1016/j.vaccine.2018.12.060
September 2018
Defining political subjectivities through encounters with biomedicine during the Ebola epidemic in Sierra Leone
In this article, the EBOVAC Social Science team revisits discussions about how unprecedented encounters with biomedicine during the West African Ebola outbreak have featured in Sierra Leoneans’ understandings of citizenship and belonging, using the case study of an Ebola vaccine trial taking place in Kambia District (EBOVAC Salone).
Analysing ethnographic material in conversation with a historical analysis of notions of belonging and citizenship, the study shows how participation in a vaccine trial in a moment of crisis allowed people to tell stories about themselves as political subjects and to situate themselves in a conversation about the nature of citizenship that both pre-dates and post-dates the epidemic.
Publication: Enria L, Lees S. (September 2018). Defining political subjectivities through encounters with biomedicine during the Ebola epidemic in Sierra Leone. Medicine Anthropology Theory. 5(4), 30-55. https://doi.org/10.17157/mat.5.4.512
September 2018
Prevac researchers highlight Ebola vaccine progress and suggest next steps in viewpoint published in The Lancet
Against the backdrop of a second Ebola outbreak in Democratic Republic of Congo in 2018, PREVAC researchers have taken stock of advances in Ebola vaccine research in a Viewpoint article for The Lancet, and highlighted the importance of continuing clinical trials.
Publication: Y Lévy et al. Prevention of Ebola virus disease through vaccination: where we are in 2018. (August 2018). The Lancet. 392(10149), 787-790. https://doi.org/10.1016/S0140-6736(18)31710-0
August 2018
Stability and suitability for storage and distribution of Ad26.ZEBOV/MVA-BN®-Filo heterologous prime-boost Ebola vaccine
The stability profile of a vaccine has important implications for storage, cold chain management and field deployment. The heterologous prime-boost Janssen Ebola vaccine regimen demonstrated an acceptable safety profile and durability of Ebola-specific immune responses in Phase I studies in healthy adults.
The findings of this study indicated that the stability of the Ad26.ZEBOV/MVA-BN-Filo is likely suitable for field deployment in regions at risk of Ebola outbreaks, where cold chain maintenance is challenging owing to infrastructure and resource limitations.
Publication: Martinus A.H.Capelle,Lara Babich, J.P. Els van Deventer-Troost, Doris Salerno, Kelly Krijgsman, Ulrike Dirmeier, Britt Raaby, Janik Adriaansen. (August 2018). Stability and suitability for storage and distribution of Ad26.ZEBOV/MVA-BN®-Filo heterologous prime-boost Ebola vaccine. European Journal of Pharmaceutics and Biopharmacetics. Vol 129, 215-221. https://doi.org/10.1016/j.ejpb.2018.06.001
June 2018
EBOVAC-Salone: lessons learned from implementing an Ebola vaccine trial in an Ebola-affected country
During the 2014–2016 West African Ebola epidemic, clinical trials were fast-tracked in order to identify prophylactic vaccines and experimental treatments that might be useful in preventing or treating Ebola. These trials included the ongoing EBOVAC-Salone study, which was established and implemented in Sierra Leone to assess the safety and immunogenicity of the Ad26.ZEBOV/MVA-BN-Filo prime-boost Ebola vaccine regimen.
This article describes the experiences of the EBOVAC-Salone social science research team in setting up and implementing the trial and provides recommendations for research teams aiming to conduct clinical trials in future outbreak situations.
Publication: Thomas Mooney, Elizabeth Smout, Bailah Leigh, Brian Greenwood, Luisa Enria, David Ishola, Daniela Manno, Mohamed Samai, Macaya Douoguih, Deborah Watson-Jones. (June 2018). EBOVAC-Salone: lessons learned from implementing an Ebola vaccine trial in an Ebola-affected country. Clinical Trials. 15(5), 436-443. https://doi.org/10.1177/1740774518780678
April 2018
“We are the heroes because we are ready to die for this country”: Participants’ Decision-making and Grounded Ethics in an Ebola vaccine clinical trial
The 2014–2016 Ebola epidemic presented a challenging setting in which to carry out clinical trials. This paper, produced by the EBOVAC Social Science team, reports findings from social science research carried out in Kambia, Northern Sierra Leone during first year of an Ebola vaccine trial (August 2015–July 2016).
Publication: Tengbeh A, Enria L, Smout E, Mooney T, Callaghan M, Ishola D, Leigh B, Watson-Jones D, Greenwood B, Larson H, Lees S . (April 2018). “We are the heroes because we are ready to die for this country”: Participants’ Decision-making and Grounded Ethics in an Ebola vaccine clinical trial. Social Science & Medicine. 203, 35-42. https://doi.org/10.1016/j.socscimed.2018.03.008
March 2018
Real-time forecasting of infectious disease dynamics with a stochastic semi-mechanistic model
Real-time forecasts of infectious diseases can help public health planning, especially during outbreaks. This paper, published as by the EBOVAC modelling team, presents a semi-mechanistic model of infectious disease dynamics that was used in real time during the 2013–2016 West African Ebola epidemic and assesses the performance of the model in different situations, identifying strengths and shortcomings of the approach. The study finds that models which combine the power of mechanistic models with the flexibility to include uncertainty about the precise outbreak dynamics, may be an important tool in combating future outbreaks.
Publication: Sebastian Funk, Anton Camacho, Adam J Kucharski, Rosalind M Eggo, W John Edmunds. (March 2018). Real-time forecasting of infectious disease dynamics with a stochastic semi-mechanistic model. Epidemics. Vol 22. 56-61. http://dx.doi.org/10.1016/j.epidem.2016.11.003
March 2017
Immune Responses to Novel Adenovirus Type 26 and Modified Vaccinia Virus Ankara–Vectored Ebola Vaccines at 1 Year
The Ebola virus vaccine strategies evaluated by the World Health Organization in response to the 2014-2016 outbreak in West Africa included a heterologous primary and booster vaccination schedule of the adenovirus type 26 vector vaccine encoding Ebola virus glycoprotein (Ad26.ZEBOV) and the modified vaccinia virus Ankara vector vaccine, encoding glycoproteins from Ebola, Sudan, Marburg, and Tai Forest viruses nucleoprotein (MVA-BN-Filo).
This paper reports the 1-year data for the study of the Ad26.ZEBOV and MVA-BN-Filo vaccines, the longest duration follow-up for any heterologous primary and booster Ebola vaccine schedule to date.
Publication: Winslow R, Milligan I, Voysey M, Luhn K, Shukarev G, Douoguih M, Snape M. (March 2017). Immune Responses to Novel Adenovirus Type 26 and Modified Vaccinia Virus Ankara–Vectored Ebola Vaccines at 1 Year. Journal of the American Medical Association. 317(10), 1075-1077. http://dx.doi.org/10.1001/jama.2016.20644
January 2017
Persistence and clearance of Ebola virus RNA from seminal fluid of Ebola virus disease survivors: a longitudinal analysis and modelling study
By January 2016, all known transmission chains of the Ebola virus disease (EVD) outbreak in West Africa had been stopped. However, there is concern about persistence of Ebola virus in the reproductive tract of men who have survived EVD. This study aimed to use biostatistical modelling to describe the dynamics of Ebola virus RNA load in seminal fluid, including clearance parameters.
Publication: Daouda Sissoko et al. (January 2017). Persistence and clearance of Ebola virus RNA from seminal fluid of Ebola virus disease survivors: a longitudinal analysis and modelling study. Lancet Global Health. 5(1), 80-88. http://dx.doi.org/10.1016/S2214-109X(16)30243-1
January 2017
Real-time dynamic modelling for the design of a cluster-randomized phase 3 Ebola vaccine trial in Sierra Leone
Declining incidence and spatial heterogeneity complicated the design of phase 3 Ebola vaccine trials during the tail of the 2013–16 Ebola virus disease (EVD) epidemic in West Africa. Mathematical models can provide forecasts of expected incidence through time and can account for both vaccine efficacy in participants and effectiveness in populations. EBOVAC modelling work shows that determining expected disease incidence was critical to calculating power and determining trial sample size.
Publication: A. Camacho, R.M. Eggo, N. Goeyvaerts, A. Vandebosch, R. Mogg, S. Funk, A.J. Kucharski, C.H. Watson, T. Vangeneugden, W.J. Edmunds. (January 2017). Real-time dynamic modelling for the design of a cluster-randomized phase 3 Ebola vaccine trial in Sierra Leone. Vaccine. 35(4) http://dx.doi.org/10.1016/j.vaccine.2016.12.019
January 2017
A two-dose heterologous prime-boost vaccine regimen eliciting sustained immune responses to Ebola Zaire could support a preventive strategy for future outbreaks
Implementation of an effective vaccination program for the containment of Ebola outbreaks necessitates a vaccine providing durable immunity. This paper reports that preliminary Phase 1 data suggest that Ad26.ZEBOV/MVA-BN-Filo, an investigational Ebola Zaire vaccine regimen that uses the heterologous prime-boost approach, confers durable immunity for at least 240 d and is well-tolerated with a good safety profile. This regimen may therefore be suitable for prophylactic use in a regional or targeted population vaccination strategy and could potentially aid prevention and control of future Ebola outbreaks.
Publication: Shukarev G, Callendret B, Luhn K, Douoguih M & the EBOVAC1 consortium. (January 2017). A two-dose heterologous prime-boost vaccine regimen eliciting sustained immune responses to Ebola Zaire could support a preventive strategy for future outbreaks. Human Vaccines & Immunotherapeutics. 13(2), 266-270. http://dx.doi.org/10.1080/21645515.2017.1264755
November 2016
Power, Fairness and Trust: understanding and engaging with vaccine trial participants and communities in the setting up the EBOVAC-Salone vaccine trial in Sierra Leone
This paper, published by the EBOVAC Social Science team, discusses the establishment of a clinical trial of an Ebola vaccine candidate in Kambia District, Northern Sierra Leone during the epidemic, and analyses the role of social science research in ensuring that lessons from the socio-political context, the recent experience of the Ebola outbreak, and learning from previous clinical trials were incorporated in the development of community engagement strategies. The paper aims to provide a case study of an integrated social science and communications system in the start-up phase of the clinical trial.
Publication: Enria L, Lees S, Smout E, Mooney T, Tengbeh A.F, Leigh B, Larson H. (November 2016). Power, Fairness and Trust: understanding and engaging with vaccine trial participants and communities in the setting up the EBOVAC-Salone vaccine trial in Sierra Leone. BMC Public Health. 16(1140). https://doi.org/10.1186/s12889-016-3799-x
April 2016
Safety and immunogenicity of Novel Adenovirus Type 26 and Modified Vaccinia Ankara-Vectored Ebola Vaccines: A Randomised Clinical Trial
The aim of this study was to evaluate an adenovirus type 26 vector vaccine encoding Ebola glycoprotein (Ad26.ZEBOV) and a modified vaccinia Ankara vector vaccine, encoding glycoproteins from Ebola virus, Sudan virus, Marburg virus, and Tai Forest virus nucleoprotein (MVA-BN-Filo).
In this phase 1 study of healthy volunteers, immunisation with Ad26.ZEBOV or MVA-BN-Filo did not result in any vaccine-related serious adverse events. An immune response was observed after primary immunisation with Ad26.ZEBOV; boosting by MVA-BN-Filo resulted in sustained elevation of specific immunity. These vaccines are being further assessed in phase 2 and 3 studies.
Publication: Milligan ID, Gibani MM, Sewell R, Clutterbuck EA, Campbell D, Plested E, Nuthall E, Voysey M, Silva-Reyes L, McElrath MJ, De Rosa SC, Frahm N, Cohen KW, Shukarev G, Orzabal N, van Duijnhoven W, Truyers C, Bachmayer N, Splinter D, Samy N, Pau MG, Schuitemaker H, Luhn K, Callendret B, Van Hoof J, Douoguih M, Ewer K, Angus B, Pollard AJ, Snape MD. (April 2016). Safety and immunogenicity of Novel Adenovirus Type 26 and Modified Vaccinia Ankara-Vectored Ebola Vaccines: A Randomised Clinical Trial. Journal of the American Medical Association. 315(15), 1610-1623. http://dx.doi.org/10.1001/jama.2016.4218
February 2016
Simulation-guided phase 3 trial design to evaluate vaccine effectiveness to prevent Ebola virus disease infection: Statistical considerations, design, rationale, and challenges
Starting in December 2013, West Africa was overwhelmed with the deadliest outbreak of Ebola virus known to date, resulting in more than 27,500 cases and 11,000 deaths. In response to the epidemic, development of a heterologous prime-boost vaccine regimen was accelerated and involved preparation of a phase 3 effectiveness study.
This manuscript, published by the EBOVAC modelling team, presents the statistical and modelling considerations, design rationale and challenges encountered due to the emergent, epidemic setting that led to the selection of a cluster-randomised phase 3 study design under field conditions.
Publication: An Vandebosch, Robin Mogg, Nele Goeyvaerts, Carla Truyers, Brian Greenwood, Debby Watson-Jones, Guillermo Herrera-Taracena, Wim Parys, Tony Vangeneugden. (February 2016). Simulation-guided phase 3 trial design to evaluate vaccine effectiveness to prevent Ebola virus disease infection: Statistical considerations, design, rationale, and challenges. Clinical Trials. 13(1), 57-65. https://doi.org/10.1177/1740774515621059
January 2016
Effectiveness of Ring Vaccination as Control Strategy for Ebola Virus Disease
Using an Ebola virus disease transmission model, this EBOVAC modelling study found that addition of ring vaccination at the outset of the West Africa epidemic might not have led to containment of this disease. However, in later stages of the epidemic or in outbreaks with less intense transmission or more effective control, this strategy could help eliminate the disease.
Publication: Adam J. Kucharski, Rosalind M. Eggo, Conall H. Watson, Anton Camacho, Sebastian Funk, W. John Edmunds. (January 2016). Effectiveness of Ring Vaccination as Control Strategy for Ebola Virus Disease. Emerging Infectious Diseases. 22(1). http://dx.doi.org/10.3201/eid2201.151410
December 2015
Duration of Ebola virus RNA persistence in semen of survivors: population-level estimates and projections
Ebola virus can persist in semen after recovery, potentially for months, which may impact the duration of enhanced surveillance required after interruption of transmission. This EBOVAC modelling study combined recent data on viral RNA persistence with weekly disease incidence to estimate the current number of semen-positive men in affected West African countries. It found that the number is low, and since few reported sexual transmission events have occurred, the future risk is also likely low, although sexual health promotion remains critical.
Publication: RM Eggo, CH Watson, A Camacho, AJ Kucharski, S Funk, WJ Edmunds. (December 2015). Duration of Ebola virus RNA persistence in semen of survivors: population-level estimates and projections. Euro surveillance. 20(48). http://dx.doi.org/10.2807/1560-7917.ES.2015.20.48.30083
December 2015
Estimating the probability of demonstrating vaccine efficacy in the declining Ebola epidemic: a Bayesian modelling approach
This article, published by the EBOVAC modelling team, reports on a study investigating the chance of demonstrating Ebola vaccine efficacy in an individually randomised controlled trial implemented in the declining epidemic of Forécariah prefecture, Guinea.
Publication: Anton Camacho, Rosalind M Eggo, Sebastian Funk, Conall H Watson, Adam J Kucharski, W John Edmunds. (December 2015). Estimating the probability of demonstrating vaccine efficacy in the declining Ebola epidemic: a Bayesian modelling approach. BMJ Open. 5(12). http://dx.doi.org/10.1136/bmjopen-2015-009346
