Clinical trial NCT05265065: Evaluation of Full Versus Fractional Dose of COVID-19 Vaccine Given as a Booster for the Prevention of COVID-19 in Adults in Mongolia.
Official title: A Randomised Controlled Trial to Assess the Immunogenicity, Safety and Reactogenicity of Standard Dose Versus Fractional Doses of COVID-19 Vaccine (Pfizer-BioNTech) Given as a Booster Dose After Priming With Sinopharm, AstraZeneca or Sputnik in Healthy Adults in Mongolia
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE3
Conditions: COVID-19
Keywords: Booster dose
Pfizer
fractional and standard doses
COVID-19 vaccination
mRNA vaccine
Lead sponsor: Murdoch Childrens Research Institute
Sponsor class: OTHER
Collaborators: name: Coalition for Epidemic Preparedness Innovations
name: The Peter Doherty Institute for Infection and Immunity
First posted: 2022-03-03
Enrollment: 601
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: Study participants who have received two doses of either Sinopharm, AstraZeneca or Sputnik vaccine as their primary vaccine will be randomised into one of two groups. The two groups consist of a standard or fractional dose of Pfizer vaccine.
Primary purpose: PREVENTION

Brief 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.

Detailed description: As per brief summary

Eligibility criteria: 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

Primary outcomes:
measure: Seroresponse
timeFrame: 28-days post booster vaccination
measure: Solicited Grade 3 or 4 Local or Systemic Reaction
timeFrame: 7 days post booster vaccination
Secondary outcomes:
measure: Seroresponse by Priming Vaccine Strata
timeFrame: 28-days post booster vaccination
measure: SARS-CoV-2 Specific IgG Antibodies at Day-28
timeFrame: 28-days post booster vaccination
measure: SARS-CoV-2 Specific IgG Antibodies at Day-28 by Priming Vaccine Strata
timeFrame: 28-days post booster vaccination
measure: SARS-CoV-2 Specific IgG Antibodies at Baseline (Pre Booster), 28- Days, 6- and 12-months Post Booster Vaccination.
timeFrame: Baseline (pre booster), 28 days, 6- and 12-months post booster vaccination
measure: SARS-CoV-2 Specific Neutralising Antibodies at Baseline (Pre Booster), 28 Days-, 6- and 12-months Post Booster Vaccination Measured by Surrogate Virus Neutralization Test (sVNT).
timeFrame: Baseline (pre booster), 28 days-, 6- and 12-months post booster vaccination
measure: SARS-CoV-2 Specific Neutralising Antibodies at Baseline (Pre Booster), 28 Days-, 6- and 12-months Post Booster Vaccination Measured by SARS-CoV-2 Microneutralisation Assay
timeFrame: Baseline (pre booster), 28 days-, 6- and 12-months post booster vaccination
measure: Interferon Gamma (IFNγ) Concentrations in International Units (IU)/mL
timeFrame: Baseline (pre booster), 28 days-, 6- and 12-months post booster vaccination
measure: Number of IFNγ Producing Cells/Million PBMCs
timeFrame: Baseline (pre booster), 28 days-, 6- and 12-months post booster vaccination
measure: Frequency of Cytokine-expressing T Cells
timeFrame: Assessed at 4 time-points (baseline, 28 days, 6 months, and 12 months)
measure: Cellular Immunity: Multiplex Cytokine Assays - Reported as Cytokine Concentrations in pg/ml and Presented as GMC and 95% CI
timeFrame: Baseline (pre booster), 28 days-, 6- and 12-months post booster vaccination
measure: Incidence of Unsolicited Adverse Events (AE)
timeFrame: 28 days-post booster vaccination
measure: Incidence of Medically Attended Adverse Events
timeFrame: 3 months post booster vaccination
measure: Incidence of Serious Adverse Events (SAE)
timeFrame: 12 months post booster vaccination
measure: Incidence of PCR Confirmed COVID-19 Infection
timeFrame: Up to 12 months post booster vaccination
Other outcomes:
Locations:
city: Ulaanbaatar
country: Mongolia
facility: District Health Centre
Study officials:
affiliation: Ministry of Health, Mongolia
name: Tsetsegsaikhan Batmunkh, MD
role: PRINCIPAL_INVESTIGATOR
affiliation: Murdoch Childrens Research Institute
name: Kim Mulholland, MD/Prof
role: PRINCIPAL_INVESTIGATOR
References:
citation: Munro APS, Janani L, Cornelius V, Aley PK, Babbage G, Baxter D, Bula M, Cathie K, Chatterjee K, Dodd K, Enever Y, Gokani K, Goodman AL, Green CA, Harndahl L, Haughney J, Hicks A, van der Klaauw AA, Kwok J, Lambe T, Libri V, Llewelyn MJ, McGregor AC, Minassian AM, Moore P, Mughal M, Mujadidi YF, Murira J, Osanlou O, Osanlou R, Owens DR, Pacurar M, Palfreeman A, Pan D, Rampling T, Regan K, Saich S, Salkeld J, Saralaya D, Sharma S, Sheridan R, Sturdy A, Thomson EC, Todd S, Twelves C, Read RC, Charlton S, Hallis B, Ramsay M, Andrews N, Nguyen-Van-Tam JS, Snape MD, Liu X, Faust SN; COV-BOOST study group. Safety and immunogenicity of seven COVID-19 vaccines as a third dose (booster) following two doses of ChAdOx1 nCov-19 or BNT162b2 in the UK (COV-BOOST): a blinded, multicentre, randomised, controlled, phase 2 trial. Lancet. 2021 Dec 18;398(10318):2258-2276. doi: 10.1016/S0140-6736(21)02717-3. Epub 2021 Dec 2.