Ethical Challenges and Lessons Learned During the Clinical Development of a Group A Meningococcal Conjugate Vaccine

Conducting an Ebola vaccine trial in a remote area of the Democratic Republic of the Congo: Challenges, mitigations, and lessons learned

Conducting a vaccine trial in a low- and middle-income country (LMIC) can present unique challenges and lessons learned. This Ebola vaccine trial, enrolling 699 healthcare providers and frontliners and jointly set up by the University of Antwerp (Sponsor) and the University of Kinshasa (Principal Investigator (PI)), was conducted in Boende, a remote city in the Democratic Republic of the Congo (DRC), between December 2019 and October 2022 (ClinicalTrials.gov: NCT04186000). While being bound by strict ICH-GCP and international funder regulations, this trial, exemplary for being a public-private partnership, required collaboration between several international stakeholders (e.g., two universities, a pharmaceutical company, and a clinical research organization), local communities and government agencies. Here we address several logistical and administrative challenges, cultural differences, language barriers and regulatory, political, and ethical considerations over the trial's 2.5-year duration, while tailoring and adapting the study to the specific local context. Lessons learned include the importance of clear communication with participants in all phases of the study, but also within the study team and among different stakeholders. Challenges, mitigations, and lessons learned are presented in nine categories (e.g., safety management; trial documentation, tools, and materials; communication, staff training and community engagement/sensitization; financial and administrative hurdles; and more). Ultimately, to reach the successful end of the vaccine trial in this remote Ebola endemic area in the DRC, careful planning, collaboration, and great flexibility and adaptability was often required from all involved partners. Despite the encountered challenges, the vaccine trial discussed in this paper was able to obtain high participant retention rates (i.e., 92% of participants completed the study). We hope that other international teams aspiring to conduct similar trials in remote areas of LMICs can learn from the way our challenges were addressed, mitigations developed, and lessons were learned.

Meningococcal vaccines and protein-energy undernutrition in children in the African meningitis belt

BACKGROUND

Vaccines to prevent meningococcal meningitis in the African meningitis belt include PsACWY, a polysaccharide-only vaccine; and PsA-TT, a polysaccharide-protein conjugate vaccine. Protein-energy undernutrition, a condition where children do not receive enough macro- or micronutrients, is related to increased risk of infectious diseases and poor immune function. Reduced immune function could affect vaccine immunogenicity. We investigated connections between protein-energy undernutrition and vaccine immunogenicity and antibody waning to PsACWY and PsA-TT in children in the African meningitis belt.

METHODS

This is a secondary analysis of data collected as part of four clinical trials testing the safety and efficacy of PsA-TT in children in Mali, Ghana, and Senegal. We identified whether anthropometric growth indices (low height-for-age, weight-for-height, or weight-for-age Z-score categories) were related to reduced vaccine-elicited antibody (measured with rabbit complement) from pre- to 1 month post-vaccination, in linear regression models. We also identified whether these growth indices were related to increased waning for vaccine-elicited antibody over time, in linear regression models.

RESULTS

A total of 697 children were included in our analysis, of which 350 (50.2%) were female; the mean (SD) age was 1.0 (1.1) years, and 578 (83.0%) received PsA-TT. In linear regression models, no consistent statistical relationship was seen between pre-vaccination anthropometric Z-score categories and vaccine immunogenicity, or decline in antibody over time, for either vaccine, although children with low weight-for-height had a greater decline in antibody from 1 to 6 months post-vaccination.

CONCLUSIONS

Our analysis did not find protein-energy undernutrition to be associated with immunogenicity or waning of PsACWY- or PsA-TT-elicited antibody in children living in the African meningitis belt. Future studies should consider measuring antibody titers at additional time points post-vaccination, and for longer periods of time, to determine if the rate of antibody waning over a period of several years is associated with protein-energy undernutrition.

Cultural considerations for informed consent in paediatric research in low/middle-income countries: a scoping review

INTRODUCTION

Conducting research with children in low/middle-income countries (LMIC) requires consideration of socioeconomic inequalities and cultural and linguistic differences. Our objective was to survey the literature on informed consent in paediatric LMIC research, assessing for practical guidance for culturally and linguistically appropriate procedures.

METHODS

We conducted a scoping review on informed consent in paediatric LMIC research searching the PubMed, Web of Science and PsycINFO databases. Eligible articles were published in English, from any date range, of any study design or format.

RESULTS

The search identified 2027 references, of which 50 were included in the analysis following full-text review. Reviewed guidelines emphasised individual, informed and voluntary consent from parents and caregivers. Reviewed articles provided detailed practical guidance on adapting these guiding principles to LMIC settings, including considerations for community engagement, verbal or other alternative consent procedures for low-literacy settings or less commonly spoken languages and guarding against therapeutic misconception by caregivers. There was uncertainty, however, on how to best protect individual autonomy, especially when influenced by gender dynamics, leadership hierarchies or the social status of researchers themselves. There was, furthermore, limited research discussing the special case of research involving adolescents or of procedures for documenting assent by participating children.

CONCLUSIONS

A scoping review of paediatric research in LMICs revealed substantial guidance on several features of culturally appropriate informed consent. However, additional research and guidance is needed, especially in the areas of gender imbalances, research with adolescents and children's own assent to participate in research.

Lessons from the Meningitis Vaccine Project

From 2001 to 2017 the Meningitis Vaccine Project (MVP), a Gates Foundation funded partnership between PATH and the World Health Organization (WHO), successfully developed, tested, licensed, and introduced an affordable new Group A meningococcal conjugate vaccine, MenAfriVac, in sub-Saharan Africa. The vaccine was well received, and from 2010 to 2016, over 260 million Africans have received a dose of the vaccine in campaigns largely directed at 1–29-year olds. The public health impact has been dramatic with the elimination of Group A meningococcal infections wherever the vaccine has been used at public health scale. Over its 16-year life span, MVP faced many challenges, and lessons were learned that may be of interest to other groups seeking to develop vaccine products for resource-poor countries. We have chosen to highlight six elements that were keys to the success of the project: (a) country and African regional engagement during all phases of the project; (b) the evolution of the WHO/PATH partnership; (c) funding the introduction of MenAfriVac in meningitis belt countries; (d) regulatory challenges; (e) clinical trials in Africa and India; and (f ) the realities of vaccine development partnerships.

New ethical considerations in vaccine trials

Known and novel pathogens continue to afflict the world's population, and we deploy existing and new vaccines - the best type of weapon we've got - against them. One consequence is that we are accumulating steadily more experience of both the scientific and the ethical requirements of conducting vaccine trials in people. Good science is itself an ethical requirement, as it is meaningless to apply ethical principles to a scientifically flawed product or plan. Bad science can only be bad ethics. And we have learned that ethical principles are a necessity when we apply the benefits of science to the improving of human health. Recent epidemics have provided opportunities to expand our understanding of this field and of the many components of it that we recognize to be necessary to the ethical assessment of vaccines.

Community Perspectives Associated With the African PsA-TT (MenAfriVac) Vaccine Trials

Background. The Meningitis Vaccine Project (MVP) was established to address epidemic meningitis as a public health problem in sub-Saharan Africa and, to that end, worked to develop a group A meningococcal conjugate vaccine, PsA-TT.

Methods. Experiences in 4 clinical trial sites are described. Culturally sensitive collaborative strategies were adopted to manage acceptable communication methods, peculiarities with the consent process, participant medical issues, community care, and death.

Results. The clinical trials were completed successfully through community acceptance and active community collaboration. The trials also strengthened the capacities in the participating communities, and actively worked to resolve community problems.

Conclusions. The understanding and integration of sociocultural realities of communities were major assets in the conduct and acceptance of these trials. MVP succeeded in these sites and provided a sound example for future clinical studies in Africa.

Clinical Trials Registration. ISRTCN78147026 (PsA-TT 002); ISRCTN87739946 (PsA-TT 003); ISRCTN82484612 (PsA-TT 004); PACTR ATMR2010030001913177 (PsA-TT 006); and PACTR201110000328305 (PsA-TT 007).