NCT04992182

Brief Summary

Preliminary data suggest that inactivated vaccine-induced neutralizing antibodies against SARS-CoV-2 decrease at six months after vaccination. Observational, unpublished data also indicate that vaccine effectiveness against Covid-19 wanes over time. Thus, the investigators aimed to determine the reactogenicity, safety, and immunogenicity of a homologous or heterologous booster of SARS-CoV-2 vaccines among people already immunized with an inactivated SARS-CoV-2 vaccine. The study focuses on the elderly population and healthcare workers.

Trial Health

43
At Risk

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Enrollment
534

participants targeted

Target at P75+ for phase_2 covid19

Timeline
Completed

Started Jul 2021

Typical duration for phase_2 covid19

Geographic Reach
1 country

2 active sites

Status
unknown

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

July 8, 2021

Completed
25 days until next milestone

First Submitted

Initial submission to the registry

August 2, 2021

Completed
3 days until next milestone

First Posted

Study publicly available on registry

August 5, 2021

Completed
26 days until next milestone

Primary Completion

Last participant's last visit for primary outcome

August 31, 2021

Completed
10 months until next milestone

Study Completion

Last participant's last visit for all outcomes

June 30, 2022

Completed
Last Updated

August 5, 2021

Status Verified

August 1, 2021

Enrollment Period

2 months

First QC Date

August 2, 2021

Last Update Submit

August 4, 2021

Conditions

Covid19

Keywords

covid-19inactivated vaccineboosterChile

Outcome Measures

Primary Outcomes (2)

  • Early humoral response

    Change in SARS-CoV-2 neutralizing antibody levels

    Baseline (90-120 days after second dose of CoronaVac) and 15 days post booster dose

  • Immunogenicity

    Change in SARS-CoV-2 neutralizing antibody levels

    Baseline, 15, 30, 60, and 90 days post booster dose

Secondary Outcomes (2)

  • Reactogenicity

    days 7, 28, and 3 months post booster dose

  • Safety of booster dose

    In addition to the scheduled visits mentioned in Outcome 3, Telephone numbers, including the PI´s cell phone will be available 24/7 throughout the study (1 year) for reporting any unsolicited reaction.

Study Arms (4)

Inactivated vaccine booster

EXPERIMENTAL

One standard IM CoronaVac dose (0.5 mL)

Biological: Inactivated vaccine booster

mRNA vaccine booster

EXPERIMENTAL

One standard IM BNT162b2 dose (0.3 mL)

Biological: mRNA vaccine booster

Viral vector vaccine booster

EXPERIMENTAL

One standard IM ChAdOx1 dose (0.5 mL)

Drug: Viral vector vaccine booster

Placebo

PLACEBO COMPARATOR

Saline solution IM (0.3 mL)

Biological: Placebo

Interventions

PlaceboBIOLOGICAL

0.3 mL IM saline solution

Placebo
Inactivated vaccine boosterBIOLOGICAL

0.5 mL IM

Also known as: CoronaVac
Inactivated vaccine booster
mRNA vaccine boosterBIOLOGICAL

0.3 mL IM

Also known as: BNT162b2
mRNA vaccine booster
Viral vector vaccine boosterDRUG

0.5 mL IM

Also known as: ChAdOx1
Viral vector vaccine booster

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Full immunization with CoronaVac (2 doses; 0,28) prior to April 15, 2021
  • Being a resident of any of the eligible Nursing Homes (located in the Metropolitan Region of Chile)
  • Healthcare workers of one of the eligible Nursing Homes.
  • Healthcare workers of Hospital de Urgencia Asistencia Publica (HUAP, Santiago, Chile)

You may not qualify if:

  • Prior history of Covid-19
  • Not able to consent

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (2)

ELEAMs (Nursing Homes)

Santiago, Chile

Location

Hospital de Urgencia Asistencia Publica

Santiago, Chile

Location

MeSH Terms

Conditions

COVID-19

Interventions

sinovac COVID-19 vaccineBNT162 Vaccine

Condition Hierarchy (Ancestors)

Pneumonia, ViralPneumoniaRespiratory Tract InfectionsInfectionsVirus DiseasesCoronavirus InfectionsCoronaviridae InfectionsNidovirales InfectionsRNA Virus InfectionsLung DiseasesRespiratory Tract Diseases

Intervention Hierarchy (Ancestors)

mRNA VaccinesNucleic Acid-Based VaccinesVaccines, SyntheticRecombinant ProteinsProteinsAmino Acids, Peptides, and ProteinsVaccinesBiological ProductsComplex MixturesCOVID-19 VaccinesViral VaccinesAntigensBiological Factors

Study Design

Study Type
interventional
Phase
phase 2
Allocation
RANDOMIZED
Masking
DOUBLE
Who Masked
PARTICIPANT, INVESTIGATOR
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Assistant Professor of Medicine, Principal Investigator

Study Record Dates

First Submitted

August 2, 2021

First Posted

August 5, 2021

Study Start

July 8, 2021

Primary Completion

August 31, 2021

Study Completion

June 30, 2022

Last Updated

August 5, 2021

Record last verified: 2021-08

Data Sharing

IPD Sharing
Will not share

Owing to data privacy regulations, the individual-level data in this study cannot be shared (Law N19.628).

Locations

CL(2)