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

Healthy Clinical Trial

Official title: 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

Clinical Trial 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.

Clinical Trial 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. ;

Related Conditions & MeSH terms

• Healthy
• Immunization; Infection
• Infections

• NCT number: NCT04824638
• Study type: Interventional
• Source: ANRS, Emerging Infectious Diseases
• Status: Completed
• Phase: Phase 2
• Start date: March 8, 2021
• Completion date: December 2, 2023