An interventional study of COVID-19 vaccinated people in COVID-19, sponsored by Hospices Civils de Lyon. Completed at 1 site in France. Open to participants aged 18 Years to 95 Years. Per ClinicalTrials.gov, last updated 2025-09-03.
Sponsored by Hospices Civils de Lyon · Not applicable, Interventional, and Prevention
Vaccination of the population is crucial in the fight against the COVID-19 pandemic. Although most available vaccines have an estimated efficacy against symptomatic infection of 65-95%, this can be significantly reduced if the patient has co-morbidities such as immunosuppression or if the full vaccination schedule is not followed. Infection with SARS-CoV-2 variants, carrying mutations, notably on the spike protein, may also be associated with escape from immunity acquired by vaccination. Indeed, in vitro studies have shown a decrease in sensitivity to neutralizing antibodies acquired after vaccination or even after infection for certain variants such as variant B.1.351 (beta variant according to the WHO, first detection in South Africa) or variant B.1.617.2. (delta variant according to the WHO, first detection in India). On the other hand, cases of COVID-19 following a full vaccination regimen have recently been reported. With the increasing detection of new variants and in the context of increasing vaccination coverage of the population, one of the priority missions of the National Reference Centre (NRC) for respiratory infection viruses is to clinically and virologically investigate all cases of infection in vaccinated patients. The main objective is to determine whether a particular variant is over-represented in vaccinated patients with an infection. The secondary objective is to study the humoral immune response in COVID-19 vaccinated patients with and without SARS-CoV-2 infection.
7,638 studies on the registry are indexed under COVID-19; 488 are open to participants now.
This study's enrollment of 1,072 is above the median of 100 across 4,098 interventional studies indexed under COVID-19.
Browse COVID-19 studies →Hospices Civils de Lyon is the lead sponsor of 1,826 studies on the registry; 439 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
- Pregnant or lactating woman
Patients with at least one dose of COVID-19 vaccine tested for SARS-CoV-2 infection with RT-PCR on respiratory specimen. RT-PCR, serological testing and viral sequencing will be applied on patient's samples
Distribution of the clade and lineage of SARS-CoV-2 in vaccinated patients
Whole genome sequencing of SARS-CoV-2 RT-PCR positive samples
Time frame: At inclusion
Titers of SARS-CoV-2 antibodies
Measurement of anti-N, anti-S antibody titers with commercial serological tests. Measurement of neutralizing antibody titers with virus neutralization assay
Time frame: At inclusion
Titers of SARS-CoV-2 antibodies
Neutralizing antibody titer measurements for different variants including graded variants of concern by Public Health France.
Time frame: At inclusion
Titers of SARS-CoV-2 antibodies
Measurement of interferon gamma titer by an ELISA method after stimulation with a peptide immunogenic
Time frame: At inclusion
This study is completed, as verified in Aug 2025. You cannot join it, but the record below documents what was studied.
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Hospices Civils de Lyon