NCT04824638

BNT162b2 Vaccination With 2 Doses in COVID-19 Negative Volunteers and With a Single Dose in COVID-19 Positive Volunteers

A Phase II Trial Assessing Immunogenicity and Safety of COVID-19 mRNA Vaccine BNT162b2 in Adult Volunteers With no History of SARS-CoV-2 Infection Administered With Two Doses of Vaccine (D1-D29) and in Adult Volunteers With Documented History of SARS-CoV-2 Infection (of More Than 5 Months) Administered With Only One Dose of Vaccine

• Status: Completed
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 267 (actual)
• Sponsor: ANRS, Emerging Infectious Diseases · Other Government
• Sex: All
• Age: 18 Years
• Healthy volunteers: Accepted

Summary

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.

Detailed description

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.

Conditions

• Healthy
• Immunization; Infection

Interventions

Type	Name	Description
BIOLOGICAL	3 doses of BNT162b2 vaccine	Administration of BNT162 b2 vaccine (30µg in 0.3mL) at D1 D29 and M8, intramuscularly (participants without antecedent of SARS-CoV-2 infection)
BIOLOGICAL	2 dose of BNT162b2 vaccine	Administration of BNT162 b2 vaccine (30µg in 0.3mL) at D1 and M8, intramuscularly (participants with antecedent of SARS-CoV-2 infection)

Timeline

• Start date: 2021-03-08
• Primary completion: 2021-06-30
• Completion: 2023-12-02
• First posted: 2021-04-01
• Last updated: 2026-04-03

Locations

11 sites across 1 country: France