As previously shown, individuals who experienced COVID-19 have developed some protective immunity to reinfection. The magnitude and duration of protection from reinfection conferred by the infection may be weaker after an asymptomatic infection as it is after a symptomatic COVID-19 episode. Moreover, it is known that immunity decreases among older adults compared to younger individuals often referred to as ''immune senescence,'' and leading to a decreased efficacy of vaccination. This study raises the question of whether a single administration of BNT162b2 in participants with prior SARS-CoV-2 infection leads to sufficient and durable immune response. We propose to evaluate the level of the single BNT162b2 vaccine dose response according to the severity of the previous SARS-CoV-2 infection in young and elderly participants with the same immunogenicity analyses to assess this response in participants receiving the two-dose vaccination regimen.
This is a national open phase II trial, assessing the immunogenicity and safety of vaccine candidate Pfizer - BNT162b2 against SARS-CoV-2 in participants with no history of SARS-CoV-2 infection receiving two doses of vaccine and in participants with history SARS-CoV-2 infection of more than 5 months and receiving only one dose of vaccine. A total of 300 volunteers will be included and vaccinated in 2 groups: Group 1: Adults with no history of SARS-CoV-2 infection(N=150) * Sub-group 1A: 18 - 45 years old: 50 volunteers * Sub-group 1B: 65 - 74 years old: 50 volunteers\* (minimum of 45) * Sub-group 1C: At least 75 years old: 50 volunteers\* (minimum of 45) Group 2: Adults with history of SARS-CoV-2 infection of more than 6 months (N=150) * Sub-group 2A: 18 - 45 years old: 50 volunteers * Sub-groupe 2B : 65 ans et plus: 100 participants Within each subgroup of the group 2, a distribution will be respected including: * 1/3 volunteers with asymptomatic COVID-19 infection, * 1/3 volunteers with mild COVID-19 infection ((symptomatic but not hospitalized or hospitalized but no oxygen required) and * 1/3 volunteers with severe COVID-19 infection (hospitalization and oxygen required). Participants within the group 1 will receive BNT162b2 (Comirnaty®) intramuscularly as a 2-dose series spaced 28 days apart at a dose of 30 µg each, then a booster dose (30µg) at M8. Participants within the group 2 will receive BNT162b2 intramuscularly as a single dose of 30 µg, then a booster dose (30µg) at M8. Analyses of humorale and saliva immune responses will be performed in differents centralized laboratories blinded for the trial group, by ELISA at Day -6/D0 (pre-vaccination sample), D29, D57, M6, M12, and M24. T and B cell analyses will be performed in a sub-group of participants Immunosenescence will be analysed in pre-vaccination samples.
Study Type
INTERVENTIONAL
Allocation
NON_RANDOMIZED
Purpose
PREVENTION
Masking
NONE
Enrollment
267
Administration of BNT162 b2 vaccine (30µg in 0.3mL) at D1 D29 and M8, intramuscularly (participants without antecedent of SARS-CoV-2 infection)
Administration of BNT162 b2 vaccine (30µg in 0.3mL) at D1 and M8, intramuscularly (participants with antecedent of SARS-CoV-2 infection)
CIC1412, CHRU Brest
Brest, France
Centre de Recherche Clinique, CHU Côte de Nacre
Caen, France
CIC 1405 , CHU Clermont-Ferrand
Clermont-Ferrand, France
CIC1430, Hôpital Henri Mondor
Créteil, France
CIC1413 , Hôtel Dieu - CHU Nantes
Nantes, France
Service des maladies infectieuses, CHU de Caremeau
Nîmes, France
CIC1417, hôpital Cochin
Paris, France
CIC 1427, Hopital Saint-Louis
Paris, France
URCI, Hôpital Lyon Sud
Pierre-Bénite, France
CIC1434, Nouvel Hôpital Civil - Hôpitaux Universitaires de Strasbourg
Strasbourg, France
...and 1 more locations
IgG humoral response to vaccine 28 days post vaccination
Anti SARS-CoV-2 Spike IgG (ELISA test) 28 days after the last injection i.e. at Day 57 in adult volunteers receiving 2 vaccine doses (group 1, without documented history of SARS-CoV-2 infection) and at Day 29 in adult volunteers receiving 1 vaccine dose (group 2, with documented history of SARS-CoV-2 infection).
Time frame: at Day 57 for patients of the group1 and at Day 29 for patient of the group 2
humoral response to vaccine
Anti SARS-CoV-2 specific IgG at Day1, Day29 (group1), Day57 (group2), \[Month8, Month8+3days\*, Month8+15 days\*, Month8+28 days (participants (\*50%)having received the additional vaccine dose)\], Month 6, Month8+6months and Month24. Anti SARS-CoV-2 IgA and IgM at Day1, Day29, Day57, Month6, Month8+6months and Month24 (all participants); Month8, Month8+28days (participants that received the additional vaccine dose).Specific neutralizing antibody to SARS-CoV-2 (all participants) and its variants (30 participants per group) by classical in vitro neutralisation assay at Day1, Day29, Day57, Month6, Month8+6months, Month24; Specific neutralizing antibody to SARS-CoV-2 at Month8, Month 8+3days\*, Month8+15days\* and Month8+28days (participants (\*50%) that received the additional vaccine dose). Specific neutralizing antibody to SARS-CoV-2 at day1, Day29, Day57, Month6, Month8+6months, Month24) (all participants). Specific neutralizing antibody to SARS-CoV-2 variants (30 participants per group
Time frame: Day 1, Day 29, Day 57, Month 6, Month 8, Month 8+3days, Month 8+15days, Month 8+28 days, Month 8+6 month, Month 24
T cells response to vaccine
Fluorospot assays (TH1, TH2, TH17, Cytotoxicity) Phenotyping of antigen specific T-Cells via Mass cytometry at Day 1 and Month24 selected from results of Fluorospot assay
Time frame: Fluorospot assays : Day 1, Day 29, Day 57, Month 6, Month 8+6months, Month 24 (all participants) and at Month 8, Month 8+28days (participants having received the additional vaccine dose). Phenotyping of antigen specific T-Cells : Day 1 and Month 24
Mucosal response to vaccine
Mucosal SARS-CoV-2 -specific antibody via measure of IgA, IgM and IgG in saliva by specific home-made and commercially available ELISA assays for salivary IgA and IgG
Time frame: Day 1, Day29, Day57, Month6, Month12, Month24 (all participants) [and Month 8, Month 8+28days, Month 8+6months (participants having received the additional vaccine dose)]
B cell response to vaccine
Determination of the epitope profiling and B Elispots as well as B cell repertoire (stereotype clonotype) of the humoral response
Time frame: Determination of the epitope profiling and B Elispots: Day1, Day57 and Month24. Determination of the B cell repertoire: Day1, Day57 [and Month8, Month8+28days (participants selected for this analysis and having received an additional dose of vaccine]
predictive determinants of vaccine response
Pre-existing serology for SARS-CoV-2 or other coronavirus, clinical profile of COVID 19 for group 2, immunosenescence profile, transcriptomic analysis, immune cell phenotype
Time frame: at screening visit : (Day -6) and at the latest day (Day 0) before the inclusion visit (Day 1)
Safety of BNT162b2 vaccine
All grade adverse reactions: * Immediate reactogenicity defined as any adverse reactions * Local and systemic reactogenicity, all grade, measured by solicited adverse reactions * Unsolicited adverse reactions Others adverse events: * Any AEs of grade ≥ 2, . * AEs leading to withdrawal . * Medically significant AEs * SAEs
Time frame: through 28 days after each dose of vaccine for reactions; throughout the study period (27 months) for others adverse events
SARS-CoV-2 infection
Occurrence of confirmed SARS-CoV-2 infection.
Time frame: during study period (27 months)
Immunological parameters
Specific neutralizing antibody to SARS-CoV-2 ; Anti SARS-CoV-2(specific to RBD) by Elisa ; Mucosal SARS-CoV-2 -specific antibody via measure of IgA and IgM in saliva ( ELISA test and specific ultrasensitive test); Fluorospot T cell assays.
Time frame: at the time of the infection to SARS Cov-2 during study period (27 months)
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