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NCT Number: NCT05543616

A Study to Learn About Variant-Adapted COVID-19 RNA Vaccine Candidate(s) in Healthy Children

The purpose of this clinical trial is to learn about the safety, extent of the side effects, and immune responses of the study vaccine (called variant-adapted BNT162b2 RNA-based vaccine) in healthy children. The trial is divided into 5 individual studies or substudies based on age group and prior history of COVID-19 vaccinations. All participants in each of the 5 sub-studies will receive study vaccine as a shot depending on what group they are in.

* Substudy A design: Phase 1 includes participants 6 months through less than 4 years 3 months of age who have not received a previous coronavirus vaccination (COVID-19 vaccine naïve) and will receive 3 doses of study vaccine as their initial series, followed by a fourth dose of study vaccine. Phase 2/3 includes participants 6 months through less than 5 years of age who have not received a previous coronavirus vaccination (COVID-19 vaccine naive) and will receive 1, 2, or 3 doses of study vaccine, depending on what group they are in. * Substudy B design: includes participants 6 months through less than 5 years of age who have either received 2 or 3 prior doses of BNT162b2 and will receive study vaccine as their third or fourth dose. * Substudy C design: Phase 1 includes participants 6 months through less than 5 years of age who have received 3 prior doses of BNT162b2 and will receive study vaccine as their fourth dose. * Substudy D design: includes participants 5 through less than12 years of age who have received 2 or 3 prior doses of BNT162b2 and will receive study vaccine as their third or fourth dose. * Substudy E design: includes participants 5 through less than 12 years of age who have not received a previous coronavirus vaccination (COVID-19 vaccine naive) and will receive a single dose of study vaccine.

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Key information

Conditions

SARS-CoV-2 Virus COVID-19 Coronaviridae Infections Coronavirus Infections Infections Lung Diseases Nidovirales Infections Pneumonia Pneumonia, Viral RNA Virus Infections Respiratory Tract Diseases Respiratory Tract Infections Severe Acute Respiratory Syndrome Coronavirus 2 Virus Diseases

Age range

6 month–11 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 3

Primary location

Obras Sociais Irma Dulce, Salvador, Estado de Bahia, Brazil

Loading trial locations.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Substudy A

Inclusion criteria

  • Phase 1: Healthy male or female participants ≥6 months to <4 years 3 months of age, at the time of randomization.
  • Phase 2/3: Healthy male or female participants ≥6 months to <5 years of age at the time of randomization/enrollment.

Exclusion criteria

  • Previous or current diagnosis of multisystem inflammatory syndrome in children (MIS-C).
  • History of severe adverse reaction associated with a vaccine and/or severe allergic reaction (eg, anaphylaxis) to any component of the study intervention(s).
  • Immunocompromised individuals with known or suspected immunodeficiency, as determined by history and/or laboratory/physical examination, or individuals who receive treatment with immunosuppressive therapy.
  • Individuals with a history of autoimmune disease or an active autoimmune disease requiring therapeutic intervention, including but not limited to systemic lupus erythematosus. Note: Stable type 1 diabetes and hypothyroidism are permitted.
  • Any history of myocarditis or pericarditis.
  • Previous vaccination with any COVID-19 vaccine.
  • Receipt of systemic treatment with known immunosuppressant medications (including cytotoxic agents or systemic corticosteroids, eg, for cancer) or radiotherapy, within 60 days before enrollment through the conclusion of the study. Systemic corticosteroids (≥2 mg/kg of body weight or ≥20 mg/day of prednisone or equivalent for persons who weigh >10 kg) for ≥14 days is prohibited from 28 days prior to enrollment through 28 days after administration of study intervention.
  • Receipt of blood/plasma products, immunoglobulin, or monoclonal antibodies (except palivizumab), from 60 days before study intervention administration, or receipt of any passive antibody therapy specific to COVID-19 from 90 days before study intervention administration, or planned receipt throughout the study.

Substudy B

Inclusion criteria

  • Healthy male or female participants = ≥6 months to <5 years of age, at the time of enrollment.

Exclusion criteria

  • Previous or current diagnosis of MIS-C.
  • History of severe adverse reaction associated with a vaccine and/or severe allergic reaction (eg, anaphylaxis) to any component of the study intervention(s).
  • Immunocompromised individuals with known or suspected immunodeficiency, as determined by history and/or laboratory/physical examination, or individuals who receive treatment with immunosuppressive therapy.
  • Individuals with a history of autoimmune disease or an active autoimmune disease requiring therapeutic intervention, including but not limited to systemic lupus erythematosus.
  • Prior receipt of any COVID 19 vaccine other than BNT162b2.
  • Receipt of systemic treatment with known immunosuppressant medications (including cytotoxic agents or systemic corticosteroids, eg, for cancer) or radiotherapy, within 60 days before enrollment through the conclusion of the study. Systemic corticosteroids (≥2 mg/kg of body weight or ≥20 mg/day of prednisone or equivalent for persons who weigh >10 kg) for ≥14 days is prohibited from 28 days prior to enrollment through 28 days after administration of study intervention.
  • Receipt of blood/plasma products, immunoglobulin, or monoclonal antibodies (except palivizumab), from 60 days before study intervention administration, or receipt of any passive antibody therapy specific to COVID-19 from 90 days before study intervention administration, or planned receipt throughout the study.

Substudy C

Inclusion criteria

  • Healthy male or female participants ≥6 months to <5 years of age, at the time of randomization/enrollment.

Exclusion criteria

  • Previous or current diagnosis of MIS-C.
  • History of severe adverse reaction associated with a vaccine and/or severe allergic reaction (eg, anaphylaxis) to any component of the study intervention(s).
  • Immunocompromised individuals with known or suspected immunodeficiency, as determined by history and/or laboratory/physical examination, or individuals who receive treatment with immunosuppressive therapy.
  • Individuals with a history of autoimmune disease or an active autoimmune disease requiring therapeutic intervention, including but not limited to systemic lupus erythematosus.
  • Prior receipt of any COVID 19 vaccine other than BNT162b2.
  • Receipt of systemic treatment with known immunosuppressant medications (including cytotoxic agents or systemic corticosteroids, eg, for cancer) or radiotherapy, within 60 days before enrollment through the conclusion of the study. Systemic corticosteroids (≥2 mg/kg of body weight or ≥20 mg/day of prednisone or equivalent for persons who weigh >10 kg) for ≥14 days is prohibited from 28 days prior to enrollment through 28 days after administration of study intervention.
  • Receipt of blood/plasma products, immunoglobulin, or monoclonal antibodies (except palivizumab), from 60 days before study intervention administration, or receipt of any passive antibody therapy specific to COVID-19 from 90 days before study intervention administration, or planned receipt throughout the study.

Substudy D

Inclusion criteria

  • Healthy male or female participants ≥5 years to <12 years of age, at the time of enrollment.

Exclusion criteria

  • Previous or current diagnosis of MIS-C.
  • History of severe adverse reaction associated with a vaccine and/or severe allergic reaction (eg, anaphylaxis) to any component of the study intervention(s).
  • Immunocompromised individuals with known or suspected immunodeficiency, as determined by history and/or laboratory/physical examination, or individuals who receive treatment with immunosuppressive therapy.
  • Individuals with a history of autoimmune disease or an active autoimmune disease requiring therapeutic intervention, including but not limited to systemic lupus erythematosus.
  • Female who is pregnant or breastfeeding.
  • Prior receipt of any COVID 19 vaccine other than BNT162b2.
  • Receipt of systemic treatment with known immunosuppressant medications (including cytotoxic agents or systemic corticosteroids, eg, for cancer) or radiotherapy, within 60 days before enrollment through the conclusion of the study. Systemic corticosteroids (≥2 mg/kg of body weight or ≥20 mg/day of prednisone or equivalent for persons who weigh >10 kg) for ≥14 days is prohibited from 28 days prior to enrollment through 28 days after administration of study intervention.
  • Receipt of blood/plasma products, immunoglobulin, or monoclonal antibodies (except palivizumab), from 60 days before study intervention administration, or receipt of any passive antibody therapy specific to COVID-19 from 90 days before study intervention administration, or planned receipt throughout the study.

Substudy E

Inclusion criteria

  • Healthy male or female participants ≥5 years to <12 years of age, at the time of enrollment.

Exclusion criteria

  • Previous or current diagnosis of MIS-C.
  • History of severe adverse reaction associated with a vaccine and/or severe allergic reaction (eg, anaphylaxis) to any component of the study intervention(s).
  • Immunocompromised individuals with known or suspected immunodeficiency, as determined by history and/or laboratory/physical examination, or individuals who receive treatment with immunosuppressive therapy.
  • Individuals with a history of autoimmune disease or an active autoimmune disease requiring therapeutic intervention, including but not limited to systemic lupus erythematosus.
  • Any history of myocarditis or pericarditis.
  • Female who is pregnant or breastfeeding.
  • Previous vaccination with any COVID 19 vaccine.
  • Receipt of systemic treatment with known immunosuppressant medications (including cytotoxic agents or systemic corticosteroids, eg, for cancer) or radiotherapy, within 60 days before enrollment through the conclusion of the study. Systemic corticosteroids (≥2 mg/kg of body weight or ≥20 mg/day of prednisone or equivalent for persons who weigh >10 kg) for ≥14 days is prohibited from 28 days prior to enrollment through 28 days after administration of study intervention.
  • Receipt of blood/plasma products, immunoglobulin, or monoclonal antibodies (except palivizumab), from 60 days before study intervention administration, or receipt of any passive antibody therapy specific to COVID-19 from 90 days before study intervention administration, or planned receipt throughout the study.

Treatment and study plan

Bivalent BNT162b2 (original/Omicron BA.4/BA.5) 3 microgram dose

Biological

Injection in the muscle

Bivalent BNT162b2 (original/Omicron BA.4/BA.5) 6 microgram dose

Biological

Injection in the muscle

Bivalent BNT162b2 (original/Omicron BA.4/BA.5) 10 microgram dose

Biological

Injection in the muscle

Variant-adapted BNT162b2 (Omicron XBB.1.5) 3 microgram dose

Biological

Injection in the muscle

Variant-adapted BNT162b2 (Omicron XBB.1.5) 6 microgram dose

Biological

Injection in the muscle

Variant-adapted BNT162b2 (Omicron XBB.1.5) 10 microgram dose

Biological

injection in the muscle

Variant-adapted BNT162b2 (Omicron KP.2) 10 microgram dose

Biological

Injection in the muscle

Primary outcomes

  1. Substudy A (SSA) - Ph 1 dose finding, percentage of participants reporting local reactions

    Time frame: for up to 7 days following Dose 1, Dose 2, Dose 3 and Dose 4

    Participants ≥6 months to <2 years of age: tenderness at the injection site, redness, and swelling as self-reported on electronic diaries Participants ≥2 to <5 years of age: pain at the injection site, redness, and swelling as self-reported on electronic diaries

  2. SSA - Ph 1 dose finding, percentage of participants reporting systemic events

    Time frame: for up to 7 days following Dose 1, Dose 2, Dose 3 and Dose 4

    Participants ≥6 months to <2 years of age: fever, decreased appetite, drowsiness, and irritability as self-reported on electronic diaries Participants ≥2 to <5 years of age: fever, fatigue, headache, chills, vomiting, diarrhea, new or worsened muscle pain, and new or worsened joint pain as self-reported on electronic diaries

  3. SSA - Ph 1 dose finding, percentage of participants reporting adverse events

    Time frame: from Dose 1 to 1 month after Dose 3 and from Dose 4 to 1 month after Dose 4

    as elicited by investigational site staff

  4. SSA - Ph 1 dose finding, percentage of participants reporting serious adverse events

    Time frame: from Dose 1 to 6 months after the last dose

    as elicited by investigational site staff

  5. SSA - Ph 2/3, percentage of participants reporting local reactions

    Time frame: for up to 7 days following Dose 1 (for Groups 1 through 6), Dose 2 (for Groups 1, 2, 3, and 6), and Dose 3 (for Group 3)

    Participants ≥6 months to <2 years of age: tenderness at the injection site, redness, and swelling as self-reported on electronic diaries Participants ≥2 to <5 years of age: pain at the injection site, redness, and swelling as self-reported on electronic diaries

  6. SSA - Ph 2/3, percentage of participants reporting systemic events

    Time frame: for up to 7 days following Dose 1 (for Groups 1 through 6), Dose 2 (for Groups 1, 2, 3, and 6), and Dose 3 (for Group 3)

    Participants ≥6 months to <2 years of age: fever, decreased appetite, drowsiness, and irritability as self-reported on electronic diaries Participants ≥2 to <5 years of age: fever, fatigue, headache, chills, vomiting, diarrhea, new or worsened muscle pain, and new or worsened joint pain as self-reported on electronic diaries

  7. SSA - Ph 2/3, percentage of participants reporting adverse events

    Time frame: from Dose 1 to 1 month after the last dose

    as elicited by investigational site staff

  8. SSA - Ph 2/3, percentage of participants reporting serious adverse events

    Time frame: from Dose 1 to 6 months after the last dose

    as elicited by investigational site staff

  9. SSA - Ph 2/3, noninferiority with respect to ratio of the geometric mean of SARS-CoV-2 Omicron XBB.1.5-neutralizing titers in participants ≥6 months to <2 years of age

    Time frame: At 1 month after 2 doses of BNT162b2 (Omicron XBB.1.5) 10 microgram (on a 0- and 8-week schedule) to 1 month after 3 doses (on a 0-, 3-, and 11-week schedule) of BNT162b2 (Omicron XBB.1.5) 3 microgram

    As measured at the central laboratory

  10. SSA - Ph 2/3, noninferiority with respect to seroresponse rate to the Omicron XBB.1.5 strain titers in participants ≥6 months to <2 years of age

    Time frame: At 1 month after 2 doses of BNT162b2 (Omicron XBB.1.5) 10 microgram (on a 0- and 8-week schedule) and at 1 month after 3 doses (on a 0-, 3-, and 11-week schedule) of BNT162b2 (Omicron XBB.1.5) 3 microgram

    As measured at the central laboratory

  11. SSA - Ph 2/3, noninferiority with respect to ratio of the geometric mean of SARS-CoV-2 Omicron XBB.1.5-neutralizing titers in participants ≥2 to <5 years of age

    Time frame: At 1 month after 1 dose of BNT162b2 (Omicron XBB.1.5) 10 microgram in participants ≥2 to <5 years of age to 1 month after 3 doses (on a 0/3/11-week schedule) of BNT162b2 (Omicron XBB.1.5) 3 microgram in participants ≥6 months to <2 years of age

    As measured at the central laboratory

  12. SSA - Ph 2/3, noninferiority with respect to seroresponse rate to the Omicron XBB.1.5 strain in participants ≥2 to <5 years of age

    Time frame: At 1 month after 1 dose of BNT162b2 (Omicron XBB.1.5) 10 microgram in participants ≥2 to <5 years of age and at 1 month after 3 doses (0/3/11-week schedule) of BNT162b2 (Omicron XBB.1.5) 3 microgram in participants ≥6 months to <2 years of age

    As measured at the central laboratory

  13. Substudy B (SSB) - percentage of participants reporting local reactions

    Time frame: for up to 7 days following Dose 1 (for Groups 1, 2 and 3) and Dose 2 (for Group 1)

    Participants ≥6 months to <2 years of age: tenderness at the injection site, redness, and swelling as self-reported on electronic diaries Participants ≥2 to <5 years of age: pain at the injection site, redness, and swelling as self-reported on electronic diaries

  14. SSB - percentage of participants reporting systemic events

    Time frame: for up to 7 days following Dose 1 (for Groups 1, 2 and 3) and Dose 2 (for Group 1)

    Participants ≥6 months to <2 years of age: fever, decreased appetite, drowsiness, and irritability as self-reported on electronic diaries Participants ≥2 to <5 years of age: fever, fatigue, headache, chills, vomiting, diarrhea, new or worsened muscle pain, and new or worsened joint pain as self-reported on electronic diaries

  15. SSB - percentage of participants reporting adverse events

    Time frame: from the first study vaccination to 1 month after the first study vaccination (for Groups 1, 2, and 3), and from the second study vaccination to 1 month after the second study vaccination (for Group 1 only)

    as elicited by investigational site staff

  16. SSB - percentage of participants reporting serious adverse events

    Time frame: from Dose 1 to 6 months after the last dose

    as elicited by investigational site staff

  17. SSB - superiority with respect to ratio of the geometric mean of SARS-CoV-2 Omicron BA.4/BA.5-neutralizing titers in participants ≥6 months to <5 years of age

    Time frame: at 1 month after Dose 4 for Group 2 participants who received 3 prior doses of BNT162b2 3 µg and a fourth dose of bivalent BNT162b2 to 1 month after Dose 3 in Study C4591007 participants ≥6 months to <5 years of age who received 3 doses of BNT162b2 3 µg

    As measured at the central laboratory

  18. SSB - noninferiority with respect to seroresponse rate to the Omicron BA.4/BA.5 strain in participants ≥6 months to <5 years of age

    Time frame: at 1 month after Dose 4 for Group 2 participants who received 3 prior doses of BNT162b2 3 µg and a fourth dose of bivalent BNT162b2 to 1 month after Dose 3 in Study C4591007 participants ≥6 months to <5 years of age who received 3 doses of BNT162b2 3 µg

    As measured at the central laboratory

  19. Substudy C (SSC) - Ph 1 dose finding, percentage of participants reporting local reactions

    Time frame: for up to 7 days following Dose 1

    Participants ≥6 months to <2 years of age: tenderness at the injection site, redness, and swelling as self-reported on electronic diaries Participants ≥2 to <5 years of age: pain at the injection site, redness, and swelling as self-reported on electronic diaries

  20. SSC - Ph 1 dose finding, percentage of participants reporting systemic events

    Time frame: for up to 7 days following Dose 1

    Participants ≥6 months to <2 years of age: fever, decreased appetite, drowsiness, and irritability as self-reported on electronic diaries Participants ≥2 to <5 years of age: fever, fatigue, headache, chills, vomiting, diarrhea, new or worsened muscle pain, and new or worsened joint pain as self-reported on electronic diaries

  21. SSC - Ph 1 dose finding, percentage of participants reporting adverse events

    Time frame: 1 month after Dose 1

    as elicited by investigational site staff

  22. SSC - Ph 1 dose finding, percentage of participants reporting serious adverse events

    Time frame: 6 months after Dose 1

    as elicited by investigational site staff

  23. SSC - Ph 1 dose finding - geometric mean titers elicited by prophylactic bivalent BNT162b2 at each dose level given as a fourth dose in participants ≥6 months to <5 years of age

    Time frame: At baseline (before Dose 1) and 1 month after Dose 1

    As measured at the central laboratory

  24. SSC - Ph 1 dose finding - geometric mean fold rise elicited by prophylactic bivalent BNT162b2 at each dose level given as a fourth dose in participants ≥6 months to <5 years of age

    Time frame: At baseline (before Dose 1) and 1 month after Dose 1

    As measured at the central laboratory

  25. SSC - Ph 1 dose finding - percentage of participants with seroresponse elicited by prophylactic bivalent BNT162b2 at each dose level given as a fourth dose in participants ≥6 months to <5 years of age

    Time frame: At baseline (before Dose 1) and 1 month after Dose 1

    As measured at the central laboratory

  26. Substudy D (SSD) - percentage of participants reporting local reactions

    Time frame: for up to 7 days following Dose 1

    pain at the injection site, redness, and swelling as self-reported on electronic diaries

  27. SSD - percentage of participants reporting systemic events

    Time frame: for up to 7 days following Dose 1

    fever, fatigue, headache, chills, vomiting, diarrhea, new or worsened muscle pain, and new or worsened joint pain as self-reported on electronic diaries

  28. SSD - percentage of participants reporting adverse events

    Time frame: 1 month after Dose 1

    as elicited by investigational site staff

  29. SSD - percentage of participants reporting serious adverse events

    Time frame: 6 months after Dose 1

    as elicited by investigational site staff

  30. SSD - the ratio of the geometric mean of SARS-CoV-2 Omicron BA.4/BA.5-neutralizing titers in participants ≥5 to <12 years of age

    Time frame: at 1 month after Dose 4 for participants who received 3 prior doses of BNT162b2 10 μg and a fourth dose of bivalent BNT162b2 to those at 1 month after Dose 3 for Study C4591007 Phase 2/3 participants who received 3 doses of BNT162b2 10 μg

    As measured at the central laboratory

  31. SSD - difference in percentages of participants with seroresponse to the Omicron BA.4/BA.5 strain in participants ≥5 to <12 years of age

    Time frame: at 1 month after bivalent BNT162b2 as a fourth dose for participants who received 3 prior doses of BNT162b2 10 µg and at 1 month after a third dose of BNT162b2 10 µg for Study C4591007 Phase 2/3 participants who received 3 doses of BNT162b2 10 µg

    As measured at the central laboratory

  32. Substudy E (SSE) - percentage of participants reporting local reactions

    Time frame: for up to 7 days following Dose 1

    pain at the injection site, redness, and swelling as self-reported on electronic diaries

  33. SSE - percentage of participants reporting systemic events

    Time frame: for up to 7 days following Dose 1

    fever, fatigue, headache, chills, vomiting, diarrhea, new or worsened muscle pain, and new or worsened joint pain as self-reported on electronic diaries

  34. SSE - percentage of participants reporting adverse events

    Time frame: from Dose 1 to 1 month after Dose 1

    as elicited by investigational site staff

  35. SSE - percentage of participants reporting serious adverse events

    Time frame: from Dose 1 to 6 months after Dose 1

    as elicited by investigational site staff

  36. SSE - Ratio of the geometric mean of SARS-CoV-2 Omicron XBB.1.5-neutralizing titers

    Time frame: At 1 month after 1 dose of BNT162b2 (Omi XBB.1.5) 10 microgram in participants ≥5 to 12 years of age to 1 month after 1 dose of BNT162b2 (Omi XBB.1.5) 30 microgram in participants ≥12 years of age from study C4591054 Substudy A

    As measured at the central laboratory

  37. SSE - difference in percentage of participants with seroresponse to Omicron XBB.1.5

    Time frame: At 1 month after 1 dose of BNT162b2 (Omi XBB.1.5) 10 microgram in participants ≥5 to 12 years of age and 1 month after 1 dose of BNT162b2 (Omi XBB.1.5) 30 microgram in participants ≥12 years of age from study C4591054 Substudy A

    As measured at the central laboratory

Secondary outcomes

  1. SSA - Ph 1 dose finding, geometric mean titers elicited by prophylactic variant-adapted BNT162b2 at each dose level and variant vaccine type (if applicable) in COVID-19 vaccine-naïve participants ≥6 months to <5 years of age

    Time frame: At baseline (before Dose 1), 1 month after Dose 2, 1 month after Dose 3, and 1 month after Dose 4

    As measured at the central laboratory

  2. SSA - Ph 1 dose finding, geometric mean fold rise elicited by prophylactic variant-adapted BNT162b2 at each dose level and variant vaccine type (if applicable) in COVID-19 vaccine-naïve participants ≥6 months to <5 years of age

    Time frame: At baseline (before Dose 1), 1 month after Dose 2, and 1 month after Dose 3

    As measured at the central laboratory

  3. SSA - Ph 1 dose finding, percentage of participants with seroresponse elicited by prophylactic variant-adapted BNT162b2 at each dose level and variant-adapted vaccine type in COVID-19 vaccine-naïve participants ≥6 months to <5 years of age

    Time frame: At baseline (before Dose 1), 1 month after Dose 2, and 1 month after Dose 3

    As measured at the central laboratory

  4. SSA - Ph 2/3, geometric mean titers elicited by variant-adapted BNT162b2 (Omicron XBB.1.5) in COVID-19 vaccine-naive participants ≥6 months to <5 years of age

    Time frame: At baseline (before Dose 1), 1 month after Dose 1 (Groups 2 and 4), 1 month after Dose 2 (Group 1), and 1 month after Dose 3 (Group 3)

    As measured at the central laboratory

  5. SSA - Ph 2/3, geometric mean fold rise elicited by variant-adapted BNT162b2 (Omicron XBB.1.5) in COVID-19 vaccine naive participants ≥6 months to <5 years of age

    Time frame: At baseline (before Dose 1), 1 month after Dose 1 (Groups 2 and 4), 1 month after Dose 2 (Group 1), and 1 month after Dose 3 (Group 3)

    As measured at the central laboratory

  6. SSA - Ph 2/3, percentages of participants with seroresponse elicited by variant-adapted BNT162b2 (Omicron XBB.1.5) in COVID-19 vaccine-naive participants ≥6 months to <5 years of age

    Time frame: At baseline (before Dose 1), 1 month after Dose 1 (Groups 2 and 4), 1 month after Dose 2 (Group 1), and 1 month after Dose 3 (Group 3)

    As measured at the central laboratory

  7. SSB - geometric mean titers elicited by bivalent BNT162b2 given as third and/or fourth dose in participants ≥6 months <5 years of age

    Time frame: Group 1: At baseline (before Dose 1), 1 month after Dose 1 and 1 month after Dose 2; Groups 2 and 3: At baseline (before Dose 1) and 1 month after Dose 1

    As measured at the central laboratory

  8. SSB - geometric mean fold rise elicited by bivalent BNT162b2 given as third and/or fourth dose in participants ≥6 months <5 years of age

    Time frame: Group 1: At baseline (before Dose 1), 1 month after Dose 1 and 1 month after Dose 2; Groups 2 and 3: At baseline (before Dose 1) and 1 month after Dose 1

    As measured at the central laboratory

  9. SSB - percentages of participants with seroresponse elicited by bivalent BNT162b2 given as third and/or fourth dose in participants ≥6 months <5 years of age

    Time frame: Group 1: At baseline (before Dose 1), 1 month after Dose 1 and 1 month after Dose 2; Groups 2 and 3: At baseline (before Dose 1) and 1 month after Dose 1

    As measured at the central laboratory

  10. SSB - noninferiority with respect to ratio of the geometric mean of SARS-CoV-2 reference strain-neutralizing titers in participants ≥6 months to <5 years of age

    Time frame: at 1 month after Dose 4 for participants who received 3 prior doses of BNT162b2 3 µg and a fourth dose of bivalent BNT162b2 to Study C4591007 participants ≥6 months to <5 years of age who received 3 doses of BNT162b2 3 µg

    As measured at the central laboratory

  11. SSB - noninferiority with respect to seroresponse rate to the reference strain in participants ≥6 months to <5 years of age

    Time frame: at 1 month after Dose 4 for participants who received 3 prior doses of BNT162b2 3 µg and a fourth dose of bivalent BNT162b2 to Study C4591007 participants ≥6 months to <5 years of age who received 3 doses of BNT162b2 3 µg

    As measured at the central laboratory

  12. SSD - geometric mean titers elicited by bivalent BNT162b2 given as a fourth dose in participants ≥5 to <12 years of age

    Time frame: At baseline (before Dose 1) and 1 month after Dose 1

    As measured at the central laboratory

  13. SSD - geometric mean fold rise elicited by bivalent BNT162b2 given as a fourth dose in participants ≥5 to <12 years of age

    Time frame: At baseline (before Dose 1) and 1 month after Dose 1

    As measured at the central laboratory

  14. SSD - percentages of participants with seroresponse elicited by bivalent BNT162b2 given as a fourth dose in participants ≥5 to <12 years of age

    Time frame: At baseline (before Dose 1) and 1 month after Dose 1

    As measured at the central laboratory

  15. SSE - geometric mean titers elicited by BNT162b2 (Omicron XBB.1.5) given as a single 10 microgram dose in participants ≥5 to <12 years of age and as a single 30 microgram dose in Study C4591054 Substudy A participants ≥12 years of age

    Time frame: At baseline (before Dose 1) and 1 month after Dose 1

    As measured at the central laboratory

  16. SSE - geometric mean fold rise elicited by BNT162b2 (Omicron XBB.1.5) given as a single 10 microgram dose in participants ≥5 to <12 years of age and as a single 30 microgram dose in Study C4591054 Substudy A participants ≥12 years of age

    Time frame: At baseline (before Dose 1) and 1 month after Dose 1

    As measured at the central laboratory

  17. SSE - percentage of participants with seroresponse elicited by BNT162b2 (Omicron XBB.1.5) given as a single 10 microgram dose in participants ≥5 to <12 years of age and as a single 30 mcg dose in Study C4591054 Substudy A participants ≥12 years of age

    Time frame: At baseline (before Dose 1) and 1 month after Dose 1

    As measured at the central laboratory

Sponsors and collaborators

Lead sponsor

BioNTech SE

Industry

Collaborators

  • Pfizer

Registry information

Official study title

A MASTER PHASE 1/2/3 PROTOCOL TO INVESTIGATE THE SAFETY, TOLERABILITY, AND IMMUNOGENICITY OF VARIANT-ADAPTED BNT162b2 RNA-BASED VACCINE CANDIDATE(S) IN HEALTHY CHILDREN

Important dates

Study start
2022
Primary completion
2026
Study completion
2026
First posted
Sep 16, 2022
Registry last updated
Apr 13, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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