PREVAIL I Cluster Vaccination Study With rVSVΔG-ZEBOV-GP as Part of a Public Health Response in Liberia.

OBJECTIVE: In November 2015, a 15-year-old boy received a diagnosis of Ebola virus disease (EVD) at the John F. Kennedy Medical Center in Monrovia, Liberia. Two additional family members received a diagnosis of EVD. The protocol for a phase 2 placebo-controlled trial of 2 Ebola vaccines was amended and approved; in 4 days, a single-arm cluster vaccination trial using the Merck rVSVΔG-ZEBOV-GP vaccine was initiated. Here, we evaluate the safety and immunogenicity of the vaccine and discuss challenges for its implementation in a small Ebola outbreak. METHOD: We conducted a ring vaccination study among contacts and contacts of close contacts of EVD cases a in Monrovia. Participants were evaluated 1 and 6 months after vaccination. RESULTS: Among 650 close contacts and contacts of close contacts of EVD cases, 210 (32%) consented and were vaccinated with rVSVΔG-ZEBOV-GP. Of those vaccinated, 189 (90%) attended the month 1 follow-up visit; 166 (79%) attended the month 6 visit. No serious adverse events were reported. Among 88 participants without an elevated antibody level at baseline, 77.3% (95% confidence interval, 68.5-86.1) had an antibody response at 1 month. CONCLUSIONS: The Merck rVSVΔG-ZEBOV-GP vaccine appeared to be safe and immunogenic among the vaccinated individuals. However, fewer than one third of eligible individuals consented to vaccination. These data may help guide implementation decisions for of cluster vaccination programs in an Ebola cluster outbreak response situation.

Design of an observational multi-country cohort study to assess immunogenicity of multiple vaccine platforms (InVITE).

In response to the COVID-19 pandemic, COVID-19 vaccines have been developed, and the World Health Oraganization (WHO) has granted emergency use listing to multiple vaccines. Studies of vaccine immunogenicity data from implementing COVID-19 vaccines by national immunization programs in single studies spanning multiple countries and continents are limited but critically needed to answer public health questions on vaccines, such as comparing immune responses to different vaccines and among different populations.

Community-based hospitals: New partners for government-sponsored clinical research during public health emergencies.

In the United States, clinical trials of COVID-19 vaccines and therapeutics quickly exhausted available clinical research capacity at large medical centers. The NIAID Division of Clinical Research tapped community hospitals to help fill the gap.

Conventional Wisdom versus Actual Outcomes: Challenges in the Conduct of an Ebola Vaccine Trial in Liberia during the International Public Health Emergency.

Clinical trials are challenging endeavors. Planning and implementing an investigational vaccine trial in Liberia, in the midst of an Ebola virus disease (EVD) epidemic that World Health Organization classified a public health emergency of international concern, presented extraordinary challenges. Normally, years of preparation and a litany of tasks lay the groundwork for a successful, randomized, blinded, placebo-controlled trial focused on safety and efficacy. Difficult research settings, unpredictable events, and other unique circumstances can add complexity. The setting in Liberia was especially problematic due to an infrastructure still badly damaged following a lengthy civil war and a very fragile health-care system that was further devastated by the EVD outbreak. The Partnership for Research on Vaccines in Liberia I EVD vaccine trial was planned and implemented in less than 3 months by a Liberian and U.S. research partnership, and its Phase II substudy was fully enrolled 3 months later. Contrasting conventional wisdom with trial outcomes offers an opportunity to compare early assumptions, barriers encountered, and adaptive strategies used, with end results. Understanding what was learned can inform future trial responses when disease outbreaks, especially in resource-poor locations with minimal infrastructure, pose a significant threat to public health.

Post-trial access to tested interventions: the views of IRB/REC chair, investigators, and research participants in a multinational HIV/AIDS study.

Controversy exists regarding an ethical requirement to make products proven effective in research available after the trial. Little is known about the views of several stakeholders. Phone or self-administered questionnaires were completed by 65 IRB/REC chairs, 117 investigators, and 500 research participants in a multinational HIV trial to assess their views about posttrial access to interventions proven effective in the study. A total of 83% of research participants, 29% of IRB/REC chairs, and 42% of researchers (p = 0.046) thought IL-2 should be guaranteed for every HIV-infected person in the world if proven effective. Most European and Latin American research participants thought IL-2 should be provided free, while North American, Australian, and Thai participants commonly said at a price the average person could afford (p < 0.001). Most IRB/REC chairs and researchers thought the CIOMS "reasonable availability" requirement applied to people in the country where the study was conducted and meant a drug should be available at a price the average person could afford and that host country governments had primary responsibility for making it available. Most research participants believe an HIV drug proven effective in research should be made available to everyone in the world who needs it. IRB/REC chairs and researchers were less expansive both in who and how they thought a drug should be guaranteed.

Regulatory approvals in a large multinational clinical trial: the ESPRIT experience.

While accepted as serving an important function to safeguard human subjects, the process of obtaining regulatory approvals to conduct clinical trials is generally regarded as cumbersome and time-consuming. For large multinational trials, U.S. federally sponsored human subject research abroad involves specific U.S. regulatory requirements, in addition to those of the host country, that act as further hurdles. These requirements may include obtaining an Assurance of Protection for Human Subjects from the Office of Human Research Protection of the U.S. Department of Health and Human Services, maintaining specific Ethics Committee/Institutional Review Board (EC/IRB) composition, and incorporating mandated elements in informed consents, all of which may differ from local policies and guidelines. Specific examples of issues that led to delays in regulatory approvals for sites participating in the multinational clinical trial entitled Evaluation of Subcutaneous Proleukin in a Randomized International Trial (ESPRIT) are presented here. While the goal of these requirements is to protect the rights and welfare of human subjects, they may create substantial delays and engender resentment over the notion of lack of respect for individual country sovereignty. Substudies within ESPRIT have been undertaken to obtain feedback from EC/IRB chairpersons, site personnel responsible for processing the required assurances, ESPRIT investigators, and study participants regarding aspects of current U.S. regulatory requirements related to human subject protection and ethical issues in multinational research. The purpose of these substudies is to compare the attitudes and experiences across countries regarding important ethical issues associated with conducting ESPRIT. One objective of the substudies is to gather additional insight to the impact of U.S. regulatory processes. Another is to help to inform the debate about how to best maximize the rights and welfare of clinical trial participants without delaying the initiation of research, while respecting the importance of national sensitivities.