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Blanda och matcha covid-19-vaccinet för säkerhet och immunogenicitet (MOSAIC)

8 november 2026 uppdaterad av: Canadian Immunization Research Network

Immunogenicitet och biverkningar efter immunisering (AEFI) med alternativa scheman för covid-19-vacciner i Kanada: är "Mix and Match" av den andra dosen (MOSAIC-1;CT24a) och tredje dosen (MOSAIC-2;CT24b) säker och immunogenic ?

The main goals of this study are to assess the immune response and safety of two different vaccines for first, second, third and fourth doses as well as for differing intervals between the first and second dose of two-dose vaccines.

Studieöversikt

Detaljerad beskrivning

For dose 1 and 2, the currently available mRNA vaccines (Pfizer-BioNTech BNT162b2 and Moderna mRNA-1273) are two dose vaccines which were studied in schedules of either 0 and 21 days or 0 and 28 days, respectively. The ChAdOx1 nCOV-19 (Astra-Zeneca) adenovirus-vectored vaccine is authorized to be given in two doses one month to 12 weeks apart. We will compare the interval 0, 28 days to a 0, 112 days (16 weeks) schedule, and assess the immunogenicity of both heterogeneous and heterologous second doses using the Canadian schedule.

For dose 3, the currently available mRNA vaccines (Pfizer-BioNTech BNT162b2 and Moderna mRNA-1273) and plant-based virus-like particle (Medicago Covifenz) are anticipated to be administered 6 months apart. We will assess the immunogenicity of both heterogeneous and heterologous third doses using the Canadian schedule.

For dose 4, the currently available mRNA vaccines (Pfizer-BioNTech BNT162b2 and Moderna mRNA-1273) and plant-based virus-like particle (Medicago Covifenz) are anticipated to be administered 3 months apart. We will assess the immunogenicity of both heterogeneous and heterologous third doses using the Canadian schedule.

Studietyp

Interventionell

Inskrivning (Faktisk)

669

Fas

  • Fas 2

Kontakter och platser

Det här avsnittet innehåller kontaktuppgifter för dem som genomför studien och information om var denna studie genomförs.

Studieorter

    • British Columbia
      • Kamloops, British Columbia, Kanada
        • Royal Inland Hospital
      • Penticton, British Columbia, Kanada
        • Penticton Regional Hospital
      • Vancouver, British Columbia, Kanada, V5Z 4H4
        • BC Children's Hospital Research Institute
    • Manitoba
      • Winnipeg, Manitoba, Kanada
        • Children's Hospital Research Institute of Manitoba
    • Nova Scotia
      • Halifax, Nova Scotia, Kanada
        • Canadian Center for Vaccinology
    • Ontario
      • Ottawa, Ontario, Kanada
        • Ottawa Hospital Research Institute, University of Ottawa
    • Quebec
      • Montreal, Quebec, Kanada, H9H 4Y6
        • McGill University Health Centre Vaccine Study Centre
      • Québec, Quebec, Kanada
        • CHU de Québec, Université Laval

Deltagandekriterier

Forskare letar efter personer som passar en viss beskrivning, så kallade behörighetskriterier. Några exempel på dessa kriterier är en persons allmänna hälsotillstånd eller tidigare behandlingar.

Urvalskriterier

Åldrar som är berättigade till studier

18 år till 99 år (Vuxen, Äldre vuxen)

Tar emot friska volontärer

Ja

Kön som är behöriga för studier

Allt

Beskrivning

Inclusion Criteria:

  1. Participant is willing and able to give written informed consent to participate in the study
  2. Age 18 years of age or older in good health or with mild or moderate stable co-morbidities at the time of enrolment
  3. Able and willing to complete all the scheduled study procedures during the whole study follow-up period
  4. If female of child-bearing potential and heterosexually active, has practiced adequate contraception for 30 days prior to injection, has a negative pregnancy test on the day of injection, and has agreed to continue adequate contraception until 3 months after the final dose of study vaccine (Please refer to the definition section for a description of child-bearing potential and adequate contraception)
  5. MOSAIC-1 Vaccine-exposed subgroups: have received or are booked to receive the first dose of an authorized COVID-19 vaccine in the 55 days prior to Visit 1 (documentation of receipt required)
  6. MOSAIC -1 Vaccine naïve subgroups: have not received an authorized COVID-19 vaccine at any time
  7. MOSAIC-2 participants have received two doses of COVID-19 vaccines authorized in Canada ≥6 months prior to study vaccine administration (documentation of receipt required)
  8. MOSAIC-3 participants have received three doses of COVID-19 vaccines authorized in Canada ≥3 months prior to study vaccine administration (documentation of receipt required)

Exclusion Criteria:

  1. Inability or unwillingness of participant or legally acceptable representative to give written informed consent
  2. Any confirmed or suspected immunosuppressive or immunodeficient state; asplenia, or immunosuppressant medication within the past 6 months except short term oral steroids (≤14 days duration) or topical steroids
  3. Current diagnosis or treatment for cancer (except basal cell carcinoma of the skin)
  4. Administration of immunoglobulins and/or any blood products within 3 months preceding the first dose of study vaccine and for one month after the last dose of study vaccine
  5. Allergy to any study vaccine or any active substance in a study vaccine
  6. Bleeding disorder or history of significant bleeding following IM injections or venipuncture
  7. Continuous use of anticoagulants
  8. A history of anaphylaxis to a previous vaccine
  9. Pregnancy or intent to become pregnant during the study or within 3 months of the last dose of study vaccine
  10. MOSAIC-1: History of laboratory-confirmed COVID-19 disease prior to enrolment by participant report
  11. Administration of a live virus vaccine within 4 weeks prior to study vaccine receipt.

Studieplan

Det här avsnittet ger detaljer om studieplanen, inklusive hur studien är utformad och vad studien mäter.

Hur är studien utformad?

Designdetaljer

  • Primärt syfte: Förebyggande
  • Tilldelning: Randomiserad
  • Interventionsmodell: Parallellt uppdrag
  • Maskning: Trippel

Vapen och interventioner

Deltagargrupp / Arm
Intervention / Behandling
Aktiv komparator: Group 1: Moderna, Moderna - 28 Days apart

Participants will be blinded and receive two doses (0.20 mg/mL each) of mRNA-1273 SARS-CoV-2 vaccine via intramuscular injection in the deltoid muscle 28 days apart.

Vaccine-exposed participants will only be blinded to, and receive, the second injection.

Contains 1.26 mg of CX-024414 mRNA and 24.38 mg of SM-102 LNP as a white to off-white dispersion in preservative-free diluent buffer at pH 7.5.

Andra namn:
  • Spikevax
  • Covid-19 Vaccin Moderna

Second injection administered 28 days post first injection

Aktiv komparator: Group 2: Moderna, Moderna - 112 days apart

Participants will be blinded and receive two doses (0.20 mg/mL each) of mRNA-1273 SARS-CoV-2 vaccine at 0.20 mg/mL via intramuscular injection in the deltoid muscle 112 days apart.

Vaccine-exposed participants will only be blinded to, and receive, the second injection.

Contains 1.26 mg of CX-024414 mRNA and 24.38 mg of SM-102 LNP as a white to off-white dispersion in preservative-free diluent buffer at pH 7.5.

Andra namn:
  • Spikevax
  • Covid-19 Vaccin Moderna

Second injection administered 112 days post first injection

Aktiv komparator: Group 3: Moderna, Pfizer/BioNTech - 28 days apart

Participants will be blinded and receive one dose (0.20 mg/mL) of mRNA-1273 SARS-CoV-2 vaccine via intramuscular injection in the deltoid muscle followed by one dose (0.3mL) of BNT162b2 vaccine after 28 days.

Vaccine-exposed participants will only be blinded to, and receive, the second injection.

Contains 1.26 mg of CX-024414 mRNA and 24.38 mg of SM-102 LNP as a white to off-white dispersion in preservative-free diluent buffer at pH 7.5.

Andra namn:
  • Spikevax
  • Covid-19 Vaccin Moderna

Second injection administered 28 days post first injection

A white to off-white, sterile, preservative-free, frozen suspension for intramuscular injection, supplied with 0.9% sodium chloride diluent for injection plastic ampoules.

Andra namn:
  • Comirnaty
  • Pfizer-BioNTech COVID-19-vaccin
Aktiv komparator: Group 4: Moderna, Pfizer/BioNTech - 112 days apart

Participants will be blinded and receive one dose (0.20 mg/mL) of mRNA-1273 SARS-CoV-2 vaccine via intramuscular injection in the deltoid muscle followed by one dose (0.3mL) of BNT162b2 vaccine after 112 days.

Vaccine-exposed participants will only be blinded to, and receive, the second injection.

Contains 1.26 mg of CX-024414 mRNA and 24.38 mg of SM-102 LNP as a white to off-white dispersion in preservative-free diluent buffer at pH 7.5.

Andra namn:
  • Spikevax
  • Covid-19 Vaccin Moderna

Second injection administered 112 days post first injection

A white to off-white, sterile, preservative-free, frozen suspension for intramuscular injection, supplied with 0.9% sodium chloride diluent for injection plastic ampoules.

Andra namn:
  • Comirnaty
  • Pfizer-BioNTech COVID-19-vaccin
Aktiv komparator: Group 5: Pfizer/BioNTech, Pfizer/BioNTech - 28 days apart

Participants will be blinded and receive two doses (0.3mL each) of BNT162b2 vaccine via intramuscular injection in the deltoid muscle 28 days apart.

Vaccine-exposed participants will only be blinded to, and receive, the second injection.

Second injection administered 28 days post first injection

A white to off-white, sterile, preservative-free, frozen suspension for intramuscular injection, supplied with 0.9% sodium chloride diluent for injection plastic ampoules.

Andra namn:
  • Comirnaty
  • Pfizer-BioNTech COVID-19-vaccin
Aktiv komparator: Group 6: Pfizer/BioNTech, Pfizer/BioNTech - 112 days apart

Participants will be blinded and receive two doses (0.3mL each) of BNT162b2 vaccine via intramuscular injection in the deltoid muscle 112 days apart.

Vaccine-exposed participants will only be blinded to, and receive, the second injection.

Second injection administered 112 days post first injection

A white to off-white, sterile, preservative-free, frozen suspension for intramuscular injection, supplied with 0.9% sodium chloride diluent for injection plastic ampoules.

Andra namn:
  • Comirnaty
  • Pfizer-BioNTech COVID-19-vaccin
Aktiv komparator: Group 7: Pfizer/BioNTech, Moderna - 28 days apart

Participants will be blinded and receive one dose (0.3mL) of BNT162b2 vaccine via intramuscular injection in the deltoid muscle followed by one dose (0.20 mg/mL) of mRNA-1273 SARS-CoV-2 vaccine after 28 days.

Vaccine-exposed participants will only be blinded to, and receive, the second injection.

Contains 1.26 mg of CX-024414 mRNA and 24.38 mg of SM-102 LNP as a white to off-white dispersion in preservative-free diluent buffer at pH 7.5.

Andra namn:
  • Spikevax
  • Covid-19 Vaccin Moderna

Second injection administered 28 days post first injection

A white to off-white, sterile, preservative-free, frozen suspension for intramuscular injection, supplied with 0.9% sodium chloride diluent for injection plastic ampoules.

Andra namn:
  • Comirnaty
  • Pfizer-BioNTech COVID-19-vaccin
Aktiv komparator: Group 8: Pfizer/BioNTech, Moderna - 112 days apart

Participants will be blinded and receive one dose (0.3mL) of BNT162b2 vaccine via intramuscular injection in the deltoid muscle followed by one dose (0.20 mg/mL) of mRNA-1273 SARS-CoV-2 vaccine after 112 days.

Vaccine-exposed participants will only be blinded to, and receive, the second injection.

Contains 1.26 mg of CX-024414 mRNA and 24.38 mg of SM-102 LNP as a white to off-white dispersion in preservative-free diluent buffer at pH 7.5.

Andra namn:
  • Spikevax
  • Covid-19 Vaccin Moderna

Second injection administered 112 days post first injection

A white to off-white, sterile, preservative-free, frozen suspension for intramuscular injection, supplied with 0.9% sodium chloride diluent for injection plastic ampoules.

Andra namn:
  • Comirnaty
  • Pfizer-BioNTech COVID-19-vaccin
Aktiv komparator: Group 9: Astra Zeneca, Moderna - 28 days apart

Participants will be blinded and receive one dose (0.5 ml) of ChAdOx1-S [recombinant] vaccine via intramuscular injection in the deltoid muscle followed by one dose (0.20 mg/mL) of mRNA-1273 SARS-CoV-2 vaccine after 28 days.

Vaccine-exposed participants will only be blinded to, and receive, the second injection.

Contains 1.26 mg of CX-024414 mRNA and 24.38 mg of SM-102 LNP as a white to off-white dispersion in preservative-free diluent buffer at pH 7.5.

Andra namn:
  • Spikevax
  • Covid-19 Vaccin Moderna

Second injection administered 28 days post first injection

A colourless to slightly brown, clear to slightly opaque solution containing 5 x 1010 viral particles (not less than 2.5 x 108 infectious units).

Andra namn:
  • Vaxzevria
  • Astra Zeneca COVID-19-vaccin
  • COVISHIELD AstraZeneca COVID-19-vaccin
Aktiv komparator: Group 10: Astra Zeneca, Moderna - 112 days apart

Participants will be blinded and receive one dose (0.5 ml) of ChAdOx1-S [recombinant] vaccine via intramuscular injection in the deltoid muscle followed by one dose (0.20 mg/mL) of mRNA-1273 SARS-CoV-2 vaccine after 112 days.

Vaccine-exposed participants will only be blinded to, and receive, the second injection.

Contains 1.26 mg of CX-024414 mRNA and 24.38 mg of SM-102 LNP as a white to off-white dispersion in preservative-free diluent buffer at pH 7.5.

Andra namn:
  • Spikevax
  • Covid-19 Vaccin Moderna

Second injection administered 112 days post first injection

A colourless to slightly brown, clear to slightly opaque solution containing 5 x 1010 viral particles (not less than 2.5 x 108 infectious units).

Andra namn:
  • Vaxzevria
  • Astra Zeneca COVID-19-vaccin
  • COVISHIELD AstraZeneca COVID-19-vaccin
Aktiv komparator: Group 11: Astra Zeneca, Pfizer/BioNTech - 28 days apart

Participants will be blinded and receive one dose (0.5 ml) of ChAdOx1-S [recombinant] vaccine via intramuscular injection in the deltoid muscle followed by one dose (0.3 mL) of BNT162b2 vaccine after 28 days.

Vaccine-exposed participants will only be blinded to, and receive, the second injection.

Second injection administered 28 days post first injection

A white to off-white, sterile, preservative-free, frozen suspension for intramuscular injection, supplied with 0.9% sodium chloride diluent for injection plastic ampoules.

Andra namn:
  • Comirnaty
  • Pfizer-BioNTech COVID-19-vaccin

A colourless to slightly brown, clear to slightly opaque solution containing 5 x 1010 viral particles (not less than 2.5 x 108 infectious units).

Andra namn:
  • Vaxzevria
  • Astra Zeneca COVID-19-vaccin
  • COVISHIELD AstraZeneca COVID-19-vaccin
Aktiv komparator: Group 12: Astra Zeneca, Pfizer/BioNTech - 112 days apart

Participants will be blinded and receive one dose (0.5 ml) of ChAdOx1-S [recombinant] vaccine via intramuscular injection in the deltoid muscle followed by one dose (0.3 mL) of BNT162b2 vaccine after 112 days.

Vaccine-exposed participants will only be blinded to, and receive, the second injection.

Second injection administered 112 days post first injection

A white to off-white, sterile, preservative-free, frozen suspension for intramuscular injection, supplied with 0.9% sodium chloride diluent for injection plastic ampoules.

Andra namn:
  • Comirnaty
  • Pfizer-BioNTech COVID-19-vaccin

A colourless to slightly brown, clear to slightly opaque solution containing 5 x 1010 viral particles (not less than 2.5 x 108 infectious units).

Andra namn:
  • Vaxzevria
  • Astra Zeneca COVID-19-vaccin
  • COVISHIELD AstraZeneca COVID-19-vaccin
Aktiv komparator: Group 1b

Participants will be blinded and receive one dose (0.3mL) of BNT162b2 vaccine via intramuscular injection in the deltoid muscle.

A white to off-white, sterile, preservative-free, frozen suspension for intramuscular injection, supplied with 0.9% sodium chloride diluent for injection plastic ampoules.

Andra namn:
  • Comirnaty
  • Pfizer-BioNTech COVID-19-vaccin
Aktiv komparator: Group 2b

Participants will be blinded and receive one half dose (0.25mL) of mRNA-1273 vaccine via intramuscular injection in the deltoid muscle.

Contains 1.26 mg of CX-024414 mRNA and 24.38 mg of SM-102 LNP as a white to off-white dispersion in preservative-free diluent buffer at pH 7.5.

Andra namn:
  • Spikevax
  • Covid-19 Vaccin Moderna
Aktiv komparator: Group 3b

Participants will be blinded and receive one half dose (0.25mL) of mRNA-1273 vaccine via intramuscular injection in the deltoid muscle.

Contains 1.26 mg of CX-024414 mRNA and 24.38 mg of SM-102 LNP as a white to off-white dispersion in preservative-free diluent buffer at pH 7.5.

Andra namn:
  • Spikevax
  • Covid-19 Vaccin Moderna
Aktiv komparator: Group 4b

Participants will be blinded and receive one dose (0.3mL) of BNT162b2 vaccine via intramuscular injection in the deltoid muscle.

A white to off-white, sterile, preservative-free, frozen suspension for intramuscular injection, supplied with 0.9% sodium chloride diluent for injection plastic ampoules.

Andra namn:
  • Comirnaty
  • Pfizer-BioNTech COVID-19-vaccin
Aktiv komparator: Group 5b

Participants will be blinded and receive one half dose (0.25mL) of mRNA-1273 vaccine via intramuscular injection in the deltoid muscle.

Contains 1.26 mg of CX-024414 mRNA and 24.38 mg of SM-102 LNP as a white to off-white dispersion in preservative-free diluent buffer at pH 7.5.

Andra namn:
  • Spikevax
  • Covid-19 Vaccin Moderna
Aktiv komparator: Group 6b

Participants will be blinded and receive one dose (0.3mL) of BNT162b2 vaccine via intramuscular injection in the deltoid muscle.

A white to off-white, sterile, preservative-free, frozen suspension for intramuscular injection, supplied with 0.9% sodium chloride diluent for injection plastic ampoules.

Andra namn:
  • Comirnaty
  • Pfizer-BioNTech COVID-19-vaccin
Aktiv komparator: Group 7b

Participants will be blinded and receive one dose (0.3mL) of BNT162b2 vaccine via intramuscular injection in the deltoid muscle.

A white to off-white, sterile, preservative-free, frozen suspension for intramuscular injection, supplied with 0.9% sodium chloride diluent for injection plastic ampoules.

Andra namn:
  • Comirnaty
  • Pfizer-BioNTech COVID-19-vaccin
Aktiv komparator: Group 8b

Participants will be blinded and receive one half dose (0.25mL) of mRNA-1273 vaccine via intramuscular injection in the deltoid muscle.

Contains 1.26 mg of CX-024414 mRNA and 24.38 mg of SM-102 LNP as a white to off-white dispersion in preservative-free diluent buffer at pH 7.5.

Andra namn:
  • Spikevax
  • Covid-19 Vaccin Moderna
Experimentell: Group 9b

Participants will receive one dose (0.5mL) of Covifenz vaccine via intramuscular injection in the deltoid muscle.

COVIFENZ is an emulsion for intramuscular injection. The 3.75 mcg antigen component of COVIFENZ is a suspension, which must be mixed 1:1 with the 0.25 mL AS03 adjuvant emulsion component prior to administration

Andra namn:
  • Medicago COVID-19-vaccin
Aktiv komparator: Group 1c

Participants will be blinded and receive one dose (0.3mL) of BNT162b2 vaccine via intramuscular injection in the deltoid muscle.

A white to off-white, sterile, preservative-free, frozen suspension for intramuscular injection, supplied with 0.9% sodium chloride diluent for injection plastic ampoules.

Andra namn:
  • Comirnaty
  • Pfizer-BioNTech COVID-19-vaccin
Aktiv komparator: Group 2c

Participants will be blinded and receive one dose (0.5mL) of Covifenz vaccine via intramuscular injection in the deltoid muscle.

COVIFENZ is an emulsion for intramuscular injection. The 3.75 mcg antigen component of COVIFENZ is a suspension, which must be mixed 1:1 with the 0.25 mL AS03 adjuvant emulsion component prior to administration

Andra namn:
  • Medicago COVID-19-vaccin
Aktiv komparator: Group 3c

Participants will be blinded and receive one half dose (0.25mL) of mRNA-1273 vaccine via intramuscular injection in the deltoid muscle.

Contains 1.26 mg of CX-024414 mRNA and 24.38 mg of SM-102 LNP as a white to off-white dispersion in preservative-free diluent buffer at pH 7.5.

Andra namn:
  • Spikevax
  • Covid-19 Vaccin Moderna
Aktiv komparator: Group 4c

Participants will be blinded and receive one dose (0.5mL) of Covifenz vaccine via intramuscular injection in the deltoid muscle.

COVIFENZ is an emulsion for intramuscular injection. The 3.75 mcg antigen component of COVIFENZ is a suspension, which must be mixed 1:1 with the 0.25 mL AS03 adjuvant emulsion component prior to administration

Andra namn:
  • Medicago COVID-19-vaccin
Aktiv komparator: Group 5c

Participants will be blinded and receive either one dose (0.3mL) of BNT162b2 or one half dose (0.25mL) of mRNA-1273 via intramuscular injection in the deltoid muscle.

Contains 1.26 mg of CX-024414 mRNA and 24.38 mg of SM-102 LNP as a white to off-white dispersion in preservative-free diluent buffer at pH 7.5.

Andra namn:
  • Spikevax
  • Covid-19 Vaccin Moderna

A white to off-white, sterile, preservative-free, frozen suspension for intramuscular injection, supplied with 0.9% sodium chloride diluent for injection plastic ampoules.

Andra namn:
  • Comirnaty
  • Pfizer-BioNTech COVID-19-vaccin
Aktiv komparator: Group 6c

Participants will be blinded and receive one dose (0.5mL) of Covifenz vaccine via intramuscular injection in the deltoid muscle.

COVIFENZ is an emulsion for intramuscular injection. The 3.75 mcg antigen component of COVIFENZ is a suspension, which must be mixed 1:1 with the 0.25 mL AS03 adjuvant emulsion component prior to administration

Andra namn:
  • Medicago COVID-19-vaccin
Experimentell: Group 7c

Participants will receive one dose (0.5mL) of Covifenz vaccine via intramuscular injection in the deltoid muscle.

COVIFENZ is an emulsion for intramuscular injection. The 3.75 mcg antigen component of COVIFENZ is a suspension, which must be mixed 1:1 with the 0.25 mL AS03 adjuvant emulsion component prior to administration

Andra namn:
  • Medicago COVID-19-vaccin

Vad mäter studien?

Primära resultatmått

Resultatmått
Åtgärdsbeskrivning
Tidsram
Antibody response to SARS-CoV-2 S protein after 2 doses
Tidsram: Day 56

The co-primary outcome for the non-inferiority comparison of 0, 28-day schedules with heterologous second dose is the immune response to SARS-CoV-2 at day 56 (28 days after the second dose of vaccine) based on anti-spike antibody titers.

Day 56
Antibody response to SARS-CoV-2 S protein after 2 doses
Tidsram: Day 140

The co-primary outcome for the non-inferiority comparison of schedules in which the timing of the second dose of vaccine is different (0, 28 days v 0, 112 days) is the immune response to SARS-CoV-2 at day 140 (28 days after the last dose in the 0, 112 day schedule) based on anti-spike antibody titers.

Day 140
Antibody response to SARS-CoV-2 S protein after 3 doses
Tidsram: Day 28

To determine if a vaccination schedule with a heterologous third dose of a COVID-19 vaccine induces a non-inferior serum immune response to SARS-CoV-2, compared to a third dose/booster with a homologous vaccine.

Day 28
Antibody response to SARS-CoV-2 S protein after 4 doses
Tidsram: Day 28

To determine if a vaccination schedule with a heterologous fourth dose of a COVID-19 vaccine induces a non-inferior serum immune response to SARS-CoV-2, compared to a third dose/booster with a homologous vaccine.

Day 28

Sekundära resultatmått

Resultatmått
Åtgärdsbeskrivning
Tidsram
Durability of antibody response to SARS-CoV-2 S over 12 months after 2 doses
Tidsram: Baseline and Days 28, 56, 112, 140, 365

Assess durability of immune responses in each study group over 12 months based on anti-spike antibody titers and pseudoneutralization assay.

Baseline and Days 28, 56, 112, 140, 365
Pseudoneutralization assay, T cell testing, Antibody dependent cellular cytotoxicity (ADCC), Antibody avidity, RNA seq after 2 doses
Tidsram: Days 28, 56, 112, 140, 365

Characterization of the immune response to COVID-19 vaccines in schedules with 0, 28 days versus 0, 112 days dosing and heterologous schedules to day 365.

Days 28, 56, 112, 140, 365
Incidence of grade 3 solicited local and systemic adverse events, SAEs, AEFIs, MAAEs, AESIs in the 7 days following vaccine receipt after 2 doses
Tidsram: From time of first study injection through Day 365.

Description of safety outcomes over 12 months post-vaccination including SAEs (serious adverse events), provincially reportable AEFIs (adverse events following immunization), MAAEs (medically attended adverse events), AESIs (adverse events of special interest).

From time of first study injection through Day 365.
Incidence of grade 3 solicited local and systemic adverse events, SAEs, AEFIs, MAAEs, AESIs in the 7 days following vaccine receipt after 3 doses
Tidsram: From time of first study injection through Day 365.

Description of safety outcomes over 12 months post-vaccination including SAEs (serious adverse events), provincially reportable AEFIs (adverse events following immunization), MAAEs (medically attended adverse events), AESIs (adverse events of special interest).

From time of first study injection through Day 365.
Acceptability of vaccines as determined by participant-completed questionnaire after 2 doses
Tidsram: Days 56, 140, and 365

Four 5 point likert scale type questions asking whether they would want to receive the vaccine again, recommend it to a friend, whether they were anxious about receiving it, and whether they would prefer a more painful injection if it conferred better protection.

Days 56, 140, and 365
Acceptability of vaccines as determined by participant-completed questionnaire after 3 doses
Tidsram: Days 28, 180

Four 5 point likert scale type questions asking whether they would want to receive the vaccine again, recommend it to a friend, whether they were anxious about receiving it, and whether they would prefer a more painful injection if it conferred better protection.

Days 28, 180
Antibody to SARS-CoV-2 S and N, RBD after 3 doses
Tidsram: Days 180 and 365

Assess durability of the immune responses in each study group over 12 months after the study vaccine.

Days 180 and 365
Pseudoneutralization assay, T cell testing, Antibody dependent cellular cytotoxicity after 3 doses
Tidsram: Day 365

Further characterize the immune response to COVID-19 vaccine in schedules with homologous and heterologous third doses to day 365

Day 365
Incidence of grade 3 solicited local and systemic adverse events, SAEs, AEFIs, MAAEs, AESIs in the 7 days following vaccine receipt after 4 doses
Tidsram: From time of first study injection through Day 365.

Description of safety outcomes over 12 months post-vaccination including SAEs (serious adverse events), provincially reportable AEFIs (adverse events following immunization), MAAEs (medically attended adverse events), AESIs (adverse events of special interest).

From time of first study injection through Day 365.
Acceptability of vaccines as determined by participant-completed questionnaire after 4 doses
Tidsram: Days 28, 180

Four 5 point likert scale type questions asking whether they would want to receive the vaccine again(Yes, definitely; Yes, probably; I don't know; No, probably not; No, definitely not), recommend it to a friend(Yes, definitely; Yes, probably; I don't know; No, probably not; No, definitely not), whether they were anxious about receiving it(Not at all; A little; Moderately; Very; Extremely), and whether they would prefer a more painful injection if it conferred better protection(Vaccine A; Vaccine B; No preference; Unsure/don't know).

Days 28, 180
Antibody to SARS-CoV-2 S and N, RBD after 4 doses
Tidsram: Days 180 and 365

Assess durability of the immune responses in each study group over 12 months after the study vaccine.

Days 180 and 365
Antibody dependent cellular cytotoxicity after 4 doses
Tidsram: Day 365

Further characterize the immune response to COVID-19 vaccine in schedules with homologous and heterologous third doses to day 365

Day 365
Pseudoneutralization assay after 4 doses
Tidsram: Day 365

Measuring the 50% Neutralization Titer to further characterize the immune response to COVID-19 vaccine in schedules with homologous and heterologous third doses to day 365

Day 365
T cell testing after 4 doses
Tidsram: Day 365

Measuring the number of T cells to further characterize the immune response to COVID-19 vaccine in schedules with homologous and heterologous third doses to day 365

Day 365

Andra resultatmått

Resultatmått
Åtgärdsbeskrivning
Tidsram
Exploratory assessment of interval between dose 1 and 2 on immune response after 3 or 4 doses
Tidsram: From time of first study injection through Day 365.

Assess the role of intervals between first and second doses of the primary immunization schedule, and between 2nd and 3rd doses, on immune responses after the third dose over the study period.

From time of first study injection through Day 365.

Samarbetspartners och utredare

Det är här du hittar personer och organisationer som är involverade i denna studie.

Studieavstämningsdatum

Dessa datum spårar framstegen för inlämningar av studieposter och sammanfattande resultat till ClinicalTrials.gov. Studieposter och rapporterade resultat granskas av National Library of Medicine (NLM) för att säkerställa att de uppfyller specifika kvalitetskontrollstandarder innan de publiceras på den offentliga webbplatsen.

Studera stora datum

Studiestart (Faktisk)

11 juni 2021

Primärt slutförande (Faktisk)

25 juli 2022

Avslutad studie (Faktisk)

16 juni 2023

Studieregistreringsdatum

Först inskickad

18 maj 2021

Först inskickad som uppfyllde QC-kriterierna

19 maj 2021

Första postat (Faktisk)

20 maj 2021

Uppdateringar av studier

Senaste uppdatering publicerad (Faktisk)

10 november 2026

Senaste inskickade uppdateringen som uppfyllde QC-kriterierna

8 november 2026

Senast verifierad

1 oktober 2026

Mer information

Denna information hämtades direkt från webbplatsen clinicaltrials.gov utan några ändringar. Om du har några önskemål om att ändra, ta bort eller uppdatera dina studieuppgifter, vänligen kontakta register@clinicaltrials.gov. Så snart en ändring har implementerats på clinicaltrials.gov, kommer denna att uppdateras automatiskt även på vår webbplats .

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