MedTrace Logo

Evaluation of Full Versus Fractional Dose of COVID-19 Vaccine Given as a Booster for the Prevention of COVID-19 in Adults in Mongolia.

NCT05265065 · Status: COMPLETED · Phase: PHASE3 · Type: INTERVENTIONAL · Enrollment: 601

Last updated 2026-03-24

Study results available
· View outcomes & findings →

Summary

This clinical trial is a single-blind, randomised study to determine the reactogenicity and immunogenicity of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) vaccine (Pfizer-BioNTech) as booster dose in adults, who have previously received either Sinopharm (BBIBP-CorV®), AstraZeneca (ChAdOx1-S, or Vaxzevria®) or Sputnik V (Gam-COVID-Vac®) as their primary doses 6 to 9 months earlier. Both standard and fractional doses will be tested.

Participants are healthy adults aged 18 years or older, with no upper age limit. Procedures will be implemented to ensure participants of all ages (aged 18 and above) are included and that there is an even age distribution (\<50 and ≥50 years) in each group. There will be a total of 6 groups (Sinopharm-standard dose Pfizer, Sinopharm-fractional dose Pfizer, AstraZeneca-standard dose Pfizer, AstraZeneca-fractional dose Pfizer, Sputnik - standard dose Pfizer, Sputnik - fractional dose Pfizer), with 200 participants per group for Sinopharm and 100 for AstraZeneca and Sputnik.

Conditions

Interventions

BIOLOGICAL

Tozinameran - Standard Dose

Tozinameran is a single-stranded, 5'-capped messenger RNA (mRNA) produced using a cellfree in vitro transcription from the corresponding DNA templates, encoding the viral spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Dose - 30 µg in 0.3 ml. Liquid for injection. Single dose.

BIOLOGICAL

Tozinameran - Fractional Dose

Tozinameran is a single-stranded, 5'-capped messenger RNA (mRNA) produced using a cellfree in vitro transcription from the corresponding DNA templates, encoding the viral spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Dose - 15 µg in 0.15 ml. Liquid for injection. Single dose.

Sponsors & Collaborators

  • Coalition for Epidemic Preparedness Innovations

    collaborator OTHER

  • The Peter Doherty Institute for Infection and Immunity

    collaborator OTHER

  • Murdoch Childrens Research Institute

    lead OTHER

Principal Investigators

  • Tsetsegsaikhan Batmunkh, MD · Ministry of Health, Mongolia

  • Kim Mulholland, MD/Prof · Murdoch Childrens Research Institute

Study Design

Allocation
RANDOMIZED
Purpose
PREVENTION
Masking
QUADRUPLE
Model
PARALLEL

Eligibility

Min Age
18 Years
Sex
ALL
Healthy Volunteers
Yes

Timeline & Regulatory

Start
2022-05-27
Primary Completion
2022-09-30
Completion
2024-11-06
FDA Drug
Yes

Countries

  • Mongolia

Study Locations

More Related Trials

Entities

Diseases

Read the full study record

This page highlights key information. For complete eligibility criteria, study locations, investigator contacts, and the full protocol, visit the original record on ClinicalTrials.gov.

View NCT05265065 on ClinicalTrials.gov