Assessing the risks of current COVID-19 challenge trials systematically.

Nir Eyal, David Wendler

Abstract read

In one paragraph

Article in Vaccine, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it

0cells of the map it votes in

1citing papers in PubMed

–field-weighted citation impact

1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

Assessing Risk Thresholds in Controlled Human Infection Models (CHIM).Bioethics · 2026
Article

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

2 authors.

Nir EyalInstitute for Health, School of Public Health, and Department of Philosophy, Rutgers University. 112 Paterson Street, Room 400, New Brunswick, NJ 08901, USA. Electronic address: nir.eyal@rutgers.edu.

David WendlerDepartment of Bioethics, National Institutes of Health, 10 Center Drive, Building 10, Room 1C118, Bethesda, MD 20892, USA. Electronic address: dwendler@cc.nih.gov.

Funding

Research and clinical care without informed consentZIACL010537 · CLC · CLINICAL CENTER · PI WENDLER, DAVID S · 2014 to 2025

$0k

Intramural NIH HHS ZIA CL010537

6 · The paper itself

Abstract

A large international collaboration has started a series of SARS-CoV-2 (COVID) human challenge trials (HCTs). However, critics of previously proposed COVID HCTs deemed them unethical for posing excessive risks to participants. These concerns raise the need to evaluate the risks of the planned COVID HCTs. Systematic analysis reveals that, although the risks of these trials would be high in some populations, they are clearly acceptable for eligible individuals and may even qualify as "minimal" for them. This conclusion is important for evaluating the planned COVID HCTs and highlights the importance of assessing the risks of later COVID HCTs and HCTs in future pandemics systematically.

Indexed as

Clinical Trials as TopicCOVID-19HumansPandemicsRisk AssessmentSARS-CoV-2AssessmentChallenge trialsCoronavirusEthicsMinimal riskRisk benefitSARS-CoV-2 omicron variant

Identifiers

PMID40016019

DOI10.1016/j.vaccine.2025.126877

PMCPMC13553212

What OpenQuestion holds

Textmetadata

Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.