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

Murdoch Childrens Research Institute

Status and phase: Completed; Phase 3

Conditions: COVID-19

Treatments: Biological: Tozinameran - Fractional Dose; Biological: Tozinameran - Standard Dose

Study type: Interventional

Funder types: Other

Identifiers

NCT05265065

81800

Details and patient eligibility

About

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.

Full description

As per brief summary

Enrollment: 601 patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

1. Have completed two doses of Sinopharm, AstraZeneca or Sputnik vaccines with the recommended schedule 6 months prior to the date of enrolment
2. Willing and able to give written informed consent
3. Aged 18 years or above
4. Willing to complete the follow-up requirements of the study

Exclusion criteria

1. Received 3 doses of COVID-19 vaccine
2. Received 2 doses of COVID-19 less than 6 months prior to the start of the trial
3. Currently on immunosuppressive medication or anti-cancer chemotherapy
4. HIV infection
5. Congenital immune deficiency syndrome
6. Has received immunoglobulin or other blood products in the 3 months prior to vaccination
7. Study staff and their relatives
8. Have a history of a severe allergic reaction to any COVID-19 vaccines or have a medical exception to receiving further COVID-19 vaccines

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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601 participants in 2 patient groups

Standard Pfizer-BioNTech booster group

Active Comparator group

Description:

Biological/Vaccine: Tozinameran - Standard Dose Other Names: BNT162b2 Comirnaty Pfizer Covid-19 vaccine 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.

Treatment:

Biological: Tozinameran - Standard Dose

Fractional Pfizer-BioNTech booster group

Experimental group

Description:

Biological/Vaccine: Tozinameran - Standard Dose Other Names: BNT162b2 Comirnaty Pfizer Covid-19 vaccine 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 0.3 ml. Liquid for injection. Single dose.

Treatment:

Biological: Tozinameran - Fractional Dose