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A Study to Learn About New COVD-19 RNA Vaccine Candidates for New Variants in Healthy Individuals

A PHASE 2/3 PROTOCOL TO INVESTIGATE THE SAFETY, TOLERABILITY, AND IMMUNOGENICITY OF BNT162b2 RNA-BASED VACCINE CANDIDATES FOR SARS-CoV-2 NEW VARIANTS IN HEALTHY INDIVIDUALS

Status
Completed
Phases
Phase 2Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05997290
Enrollment
1051
Registered
2023-08-18
Start date
2023-08-10
Completion date
2025-03-13
Last updated
2026-04-28

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

COVID-19, SARS-CoV-2 Infection

Keywords

COVID-19, Coronavirus, Vaccine, SARS-CoV-2, RNA Vaccine, Vaccine-naïve

Brief summary

The purpose of this clinical protocol is to learn about the safety, tolerability, and immunogenicity of new BNT162b2 RNA-based vaccine candidates targeting new variants of SARS-CoV-2 in healthy people. Substudy A: * This study will evaluate the safety, tolerability, and immunogenicity of BNT162b2 (Omi XBB.1.5) given as a single 30 µg dose, * in people who are 12 years of age and older, * who previously received at least 3 doses of a US-authorized mRNA COVID-19 vaccine, with the most recent dose being an Omicron BA.4/BA.5-adapted bivalent vaccine received at least 150 days before the study vaccination (Visit 1). * The study is about 6 months long for each participant. * Participants will have at least 5 visits to the clinic. * At each clinic visit a blood sample will be taken. * At least 1 nasal swab will taken. Substudy B: * This study will evaluate the safety, tolerability, and immunogenicity of BNT162b2 (Omi XBB.1.5) given as a single 30 µg dose, * in people who are 12 years of age and older, * who are COVID-19 vaccine-naïve * who have had any positive SARS-CoV-2 test result \>28 days before study vaccine administration. * The study is about 6 months long for each participant. * Participants will have at least 5 visits to the clinic. * At each clinic visit a blood sample will be taken. * At least 1 nasal swab will taken. Substudy C: * This study will evaluate the safety, tolerability, and immunogenicity of BNT162b2 (Omi JN.1) and BNT162b2 (Omi KP.2) given as a single 30 µg dose to: * Cohort 1: people who are 18 years of age and older, who will receive BNT162b2 (Omi JN.1), and, * Cohort 2: people who are 12 years of age and older, who will receive BNT162b2 (Omi JN.1), and, * Cohort 3: people who are 18 years of age and older who will receive BNT162b2 (Omi KP.2). * Participants may have never received a COVID-19 vaccine or, may have previously received COVID-19 vaccine(s), with the most recent dose received at least 150 days before the study vaccination (Visit 1). * The study is about 6 months long for each participant. * Participants will have at least 6 visits (Cohorts 1 and 3) or at least 5 visits (Cohort 2) to the clinic. * At each clinic visit a blood sample will be taken. * At least 1 nasal swab will taken.

Interventions

BNT162b2 monovalent (Omicron XBB.1.5)

BIOLOGICALBNT162b2 (Omi JN.1)

BNT162b2 monovalent (Omicron JN.1)

BIOLOGICALBNT162b2 (Omi KP.2)

BNT162b2 monovalent (Omicron KP.2)

Sponsors

BioNTech SE
Lead SponsorINDUSTRY
Pfizer
CollaboratorINDUSTRY

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
PREVENTION
Masking
NONE

Masking description

Open-label

Intervention model description

Phase 2/3, controlled study

Eligibility

Sex/Gender
ALL
Age
12 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

SSA Inclusion Criteria: * Received at least 3 prior doses of a US-authorized mRNA COVID-19 vaccine, with the most recent dose being a US-authorized Omicron BA.4/BA.5-adapted bivalent vaccine received at least 150 days before Visit 1 (Day 1). * 12 years of age and older * Healthy participants (stable pre-existing disease permitted). * Willing and able to comply with all scheduled visits/contacts, study procedures and lifestyle considerations. * Capable of giving, or parent(s)/legal guardian capable of giving, signed informed consent.

Exclusion criteria

* History of severe adverse reaction associated with a vaccine and/or severe allergic reaction (eg, anaphylaxis) to any component of the study vaccines. * Immunocompromised with known or suspected immunodeficiency, as determined by history and/or laboratory/physical examination. * Bleeding diathesis or condition associated with prolonged bleeding that would, in the opinion of the investigator, contraindicate intramuscular injection. * Women who are pregnant or breastfeeding. * Any medical or psychiatric condition, or laboratory abnormality that may increase the risk of study participation or, in the investigator's judgment, make the participant inappropriate for the study. * History of myocarditis or pericarditis. * Receipt of systemic treatment with known immunosuppressant medications (including cytotoxic agents or systemic corticosteroids, eg, for cancer or an autoimmune disease), or radiotherapy, within 60 days before enrollment or planned receipt through conclusion of the study. * Receipt of blood/plasma products, immunoglobulin, or monoclonal antibodies, used for the treatment or prevention of COVID-19 or those that are considered immunosuppressive, from 60 days before study vaccination or planned receipt throughout the study. * Participation in other studies involving receipt of other study intervention within 28 days before enrollment. Anticipated participation in other studies involving other study intervention from enrollment through the end of this study. * Investigator site staff directly involved in the conduct of the study and their family members, site staff otherwise supervised by the investigator, and sponsor and sponsor delegate employees directly involved in the conduct of the study and their family members. SSB Inclusion Criteria: * COVID-19 vaccine-naïve. * Any positive SARS-CoV-2 test result \>28 days before study intervention administration. * 12 years of age and older. * Healthy participants (stable pre-existing disease permitted). * Willing and able to comply with all scheduled visits/contacts, study procedures and lifestyle considerations. * Capable of giving or parent(s)/legal guardian capable of giving, signed informed consent.

Design outcomes

Primary

MeasureTime frameDescription
Percentage of Participants With Local Reactions Within 7 Days After Vaccination: SSADay 1 to Day 7 after vaccinationLocal reactions: pain at injection site, redness and swelling were recorded by participants in an electronic diary (e-diary) or as adverse events (AEs) in the case report form (CRF). Redness and swelling were recorded in measuring device units (mdu) (range: 1 to 21), 1 mdu =0.5 centimeter (cm) and were graded as mild (greater than \[\>\] 2.0 to 5.0 cm), moderate (\>5.0 to 10.0 cm), severe (\>10.0 cm) and Grade 4 (necrosis \[swelling\] and necrosis or exfoliative dermatitis \[redness\]). Pain at injection site was graded as mild (did not interfere with activity), moderate (interfered with activity), severe (prevented daily activity) and Grade 4 (emergency room \[ER\] visit or hospitalization for severe pain at injection site). Grade 4 local reactions were classified by investigator or medically qualified person.
Percentage of Participants With Systemic Events Within 7 Days After Vaccination: SSADay 1 to Day 7 after vaccinationSystemic events were recorded by participants in an e-diary or as AEs in the CRF. Fever: defined as oral temperature more than or equal to (\>=38) degree Celsius (C) and categorized as \>= 38.0 to 38.4 degree C, \>38.4 to 38.9 degree C, \>38.9 to 40.0 degree C and \>40.0 degree C. Fatigue, headache, chills, new or worsened muscle pain and joint pain were graded as: mild (did not interfere with activity), moderate (some interference with activity), severe (prevented daily routine activity). Vomiting: mild: 1-2 times in 24 hours (h), moderate: \>2 times in 24h, severe: required intravenous (IV) hydration. Diarrhea was graded as: mild: 2-3 loose stools in 24h, moderate: 4-5 loose stools in 24h, severe: 6 or more loose stools in 24h. Grade 4 for all events except fever: ER visit/hospitalization. Grade 4 systemic events were classified by investigator or medically qualified person.
Percentage of Participants With Adverse Events (AEs) From Vaccination Through 1 Month After Vaccination: SSAFrom vaccination on Day 1 up to 1 month after vaccinationAn AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with use of study intervention, whether or not considered related to study intervention. A serious AE (SAE) was defined as any untoward medical occurrence at any dose that resulted in any of the following outcomes: death; life-threatening; required inpatient hospitalization or prolongation of existing hospitalization; persistent or significant disability/incapacity; congenital anomaly/birth defect, any other event pre-specified in protocol of the study; or considered as an important medical event. AEs included both SAEs and all non-SAEs. Only AEs collected by non-systematic assessment (i.e., excluding local reactions and systemic events) were reported in this outcome measure.
Percentage of Participants With SAEs From Vaccination Through 6 Months After the Study Vaccination: SSAFrom vaccination on Day 1 up to 6 months after vaccinationAn AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. A SAE was defined as any untoward medical occurrence at any dose that resulted in any of the following outcomes: death; life-threatening; required inpatient hospitalization or prolongation of existing hospitalization; persistent or significant disability/incapacity; congenital anomaly/birth defect, any other event pre-specified in protocol of the study; or considered as an important medical event.
Geometric Mean Titers (GMT) of SARS-CoV-2 Omi XBB.1.5-Neutralizing Titers at 1 Month After Vaccination: SSA and Historical Control of the Bivalent BNT162b2 (WT/Omi BA.4/BA.5) Group From Study C4591044At 1 month after vaccinationGMTs and 2-sided 95 percentage (%) confidence interval (CIs) were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). Assay results below the lower limit of quantitation (LLOQ) were set to 0.5\*LLOQ.
GMT of SARS-CoV-2 Omi BA.4/BA.5-Neutralizing Titers at 1 Month After Vaccination: SSA and Historical Control of the Bivalent BNT162b2 (WT/Omi BA.4/BA.5) Group From Study C4591044At 1 month after vaccinationGMTs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ were set to 0.5\*LLOQ.
Geometric Mean Fold Rise (GMFR) of SARS-CoV-2 Omi XBB.1.5-Neutralizing Titers From Before Study Vaccination to 1 Month After Vaccination: SSA and Historical Control of Bivalent BNT162b2 (WT/Omi BA.4/BA.5) Group From Study C4591044From before vaccination on Day 1 up to 1 month after vaccinationGMFRs were defined as geometric mean ratios of the results after vaccination to the results before vaccination. GMFR and 2-sided 95% CI were calculated by exponentiating the mean logarithm of fold rises and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ were set to 0.5\*LLOQ.
GMFR of SARS-CoV-2 Omi BA.4/BA.5-Neutralizing Titers From Before Vaccination to 1 Month After Vaccination: SSA and Historical Control of the Bivalent BNT162b2 (WT/Omi BA.4/BA.5) Group From Study C4591044From before vaccination on Day 1 up to 1 month after vaccinationGMFRs were defined as geometric mean ratios of the results after vaccination to the results before vaccination. GMFR and 2-sided 95% CI were calculated by exponentiating the mean logarithm of fold rises and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ were set to 0.5\*LLOQ.
Percentage of Participants With Seroresponse to SARS-CoV-2 Omi XBB.1.5-Neutralizing Titers at 1 Month After Vaccination: SSA and Historical Control of the Bivalent BNT162b2 (WT/Omi BA.4/BA.5) Group From Study C4591044At 1 month after vaccinationSeroresponse was defined as achieving \>= 4-fold rise from baseline (before the study vaccination). If the baseline measurement was below the LLOQ, the postvaccination assay result of \>= 4\* LLOQ was considered a seroresponse.
Percentage of Participants With Seroresponse to SARS-CoV-2 Omi BA.4/BA.5-Neutralizing Titers at 1 Month After Vaccination: SSA and Historical Control of the Bivalent BNT162b2 (WT/Omi BA.4/BA.5) Group From Study C4591044At 1 month after vaccinationSeroresponse was defined as achieving \>= 4-fold rise from baseline (before the study vaccination). If the baseline measurement was below the LLOQ, the postvaccination assay result of \>= 4\* LLOQ was considered a seroresponse.
Percentage of Participants With Local Reactions Within 7 Days After Vaccination: SSBDay 1 to Day 7 after vaccinationLocal reactions: pain at injection site, redness and swelling were recorded by participants in an e-diary or as AEs in the CRF. Redness and swelling were recorded in mdu (range:1 to 21), 1 mdu= 0.5 cm and were graded as mild (\>2.0 to 5.0 cm), moderate (\>5.0 to 10.0 cm), severe (\>10.0 cm) and Grade 4 (necrosis \[swelling\] and necrosis or exfoliative dermatitis \[redness\]). Pain at injection site was graded as mild (did not interfere with activity), moderate (interfered with activity), severe (prevented daily activity) and Grade 4 (ER visit or hospitalization for severe pain at injection site). Grade 4 local reactions were classified by investigator or medically qualified person.
Percentage of Participants With Systemic Events Within 7 Days After Vaccination: SSBDay 1 to Day 7 after vaccinationSystemic events were recorded by participants in an e-diary or as AEs in the CRF. Fever: defined as oral temperature \>=38 degree C and categorized as \>= 38.0 to 38.4 degree C, \>38.4 to 38.9 degree C, \>38.9 to 40.0 degree C and \>40.0 degree C. Fatigue, headache, chills, new or worsened muscle pain and joint pain were graded as: mild (didn't interfere with activity), moderate (some interference with activity), severe (prevented daily routine activity). Vomiting: mild: 1-2 times in 24h, moderate: \>2 times in 24h, severe: required IV hydration. Diarrhea were graded as: mild: 2-3 loose stools in 24h, moderate: 4-5 loose stools in 24h, severe: 6 or more loose stools in 24h. Grade 4 for all events except fever: ER visit/hospitalization. Grade 4 systemic events were classified by investigator or medically qualified person.
Percentage of Participants With AEs From Vaccination Through 1 Month After Vaccination: SSBFrom vaccination on Day 1 up to 1 month after vaccinationAn AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with use of study intervention, whether or not considered related to study intervention. A SAE was defined as any untoward medical occurrence at any dose that resulted in any of the following outcomes: death; life-threatening; required inpatient hospitalization or prolongation of existing hospitalization; persistent or significant disability/incapacity; congenital anomaly/birth defect, any other event pre-specified in protocol of the study; or considered as an important medical event. AEs included both SAEs and all non-SAEs. Only AEs collected by non-systematic assessment (i.e., excluding local reactions and systemic events) were reported in this outcome measure.
Percentage of Participants With SAEs From Vaccination Through 6 Months After the Study Vaccination: SSBFrom vaccination on Day 1 up to 6 months after vaccinationAn AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. A SAE was defined as any untoward medical occurrence at any dose that resulted in any of the following outcomes: death; life-threatening; required inpatient hospitalization or prolongation of existing hospitalization; persistent or significant disability/incapacity; congenital anomaly/birth defect, any other event pre-specified in protocol of the study; or considered as an important medical event.
Geometric Mean Ratio (GMR) of the SARS-CoV-2 XBB.1.5-Neutralizing Titers 1 Month After BNT162b2 (Omi XBB.1.5) COVID-19 Vaccine-Naive Participants in SSB Versus Vaccine-Experienced Participants in SSAAt 1 month after vaccinationGMTs / GMRs and 2-sided 95% CIs were calculated by exponentiating the least square (LS) means / difference of LS means and the corresponding CIs based on analysis of log-transformed assay results using a linear regression model with baseline assay results (log scale), age and vaccine group as covariates. Assay results below the LLOQ were set to 0.5\*LLOQ. GMT was reported in descriptive section and GMR was reported in statistical analysis section
Percentage of Participants and Difference in Percentage of Participants With Seroresponse to the XBB.1.5 Strain 1 Month After BNT162b2 (Omi XBB.1.5) COVID-19 Vaccine Naive Participants in SSB Versus Vaccine-Experienced Participants in SSAAt 1 month after vaccinationSeroresponse was defined as achieving \>=4-fold rise from baseline (before the study vaccination). If the baseline measurement was below the LLOQ, the postvaccination assay result of \>= 4\* LLOQ was considered a seroresponse. Percentage of participants with seroresponse were reported in descriptive section and difference in percentage of participants with seroresponse in SSB: All Age Groups (Vaccine Naive)- SSA: All Age Groups (Vaccine Experienced Control) were reported in statistical analysis section.
Percentage of Participants With Local Reactions Within 7 Days After Vaccination: SSC Cohort 2; SSC Cohort 1 and 2 CombinedDay 1 to Day 7 after vaccinationLocal reactions: pain at injection site, redness and swelling were recorded by participants in an e-diary or as AEs in the CRF. Redness and swelling were recorded in mdu (range:1 to 21), 1 mdu= 0.5 cm and were graded as mild (\>2.0 to 5.0 cm), moderate (\>5.0 to 10.0 cm), severe (\>10.0 cm) and Grade 4 (necrosis \[swelling\] and necrosis or exfoliative dermatitis \[redness\]). Pain at injection site was graded as mild (did not interfere with activity), moderate (interfered with activity), severe (prevented daily activity) and Grade 4 (ER visit or hospitalization for severe pain at injection site). Grade 4 local reactions were classified by investigator or medically qualified person.
Percentage of Participants With Systemic Events Within 7 Days After Vaccination: SSC Cohort 2; SSC Cohort 1 and 2 CombinedDay 1 to Day 7 after vaccinationSystemic events were recorded by participants in an e-diary or as AEs in the CRF. Fever: defined as oral temperature \>=38 degree C and categorized as \>= 38.0 to 38.4 degree C, \>38.4 to 38.9 degree C, \>38.9 to 40.0 degree C and \>40.0 degree C. Fatigue, headache, chills, new or worsened muscle pain and joint pain were graded as: mild (didn't interfere with activity), moderate (some interference with activity), severe (prevented daily routine activity). Vomiting: mild: 1-2 times in 24h, moderate: \>2 times in 24h, severe: required IV hydration. Diarrhea were graded as: mild: 2-3 loose stools in 24h, moderate: 4-5 loose stools in 24h, severe: 6 or more loose stools in 24h. Grade 4 for all events except fever: ER visit/hospitalization. Grade 4 systemic events were classified by investigator or medically qualified person.
Percentage of Participants With AEs From Vaccination Through 1 Month After Vaccination: SSC Cohort 2; SSC Cohort 1 and 2 CombinedFrom vaccination on Day 1 up to 1 month after vaccinationAn AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with use of study intervention, whether or not considered related to study intervention. A SAE was defined as any untoward medical occurrence at any dose that resulted in any of the following outcomes: death; life-threatening; required inpatient hospitalization or prolongation of existing hospitalization; persistent or significant disability/incapacity; congenital anomaly/birth defect, any other event pre-specified in protocol of the study; or considered as an important medical event. AEs included both SAEs and all non-SAEs. Only AEs collected by non-systematic assessment (i.e., excluding local reactions and systemic events) were reported in this outcome measure.
Percentage of Participants With SAEs From Vaccination Through 6 Months After the Study Vaccination: SSC Cohort 2; SSC Cohort 1 and 2 CombinedFrom vaccination on Day 1 up to 6 months after vaccinationAn AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. A SAE was defined as any untoward medical occurrence at any dose that resulted in any of the following outcomes: death; life-threatening; required inpatient hospitalization or prolongation of existing hospitalization; persistent or significant disability/incapacity; congenital anomaly/birth defect, any other event pre-specified in protocol of the study; or considered as an important medical event.
Percentage of Participants With Local Reactions Within 7 Days After Vaccination: SSC Cohort 3Day 1 to Day 7 after vaccinationLocal reactions: pain at injection site, redness and swelling were recorded by participants in an e-diary or as AEs in the CRF. Redness and swelling were recorded in mdu (range:1 to 21), 1 mdu= 0.5 cm and were graded as mild (\>2.0 to 5.0 cm), moderate (\>5.0 to 10.0 cm), severe (\>10.0 cm) and Grade 4 (necrosis \[swelling\] and necrosis or exfoliative dermatitis \[redness\]). Pain at injection site was graded as mild (did not interfere with activity), moderate (interfered with activity), severe (prevented daily activity) and Grade 4 (ER visit or hospitalization for severe pain at injection site). Grade 4 local reactions were classified by investigator or medically qualified person.
Percentage of Participants With Systemic Events Within 7 Days After Vaccination: SSC Cohort 3Day 1 to Day 7 after vaccinationSystemic events were recorded by participants in an e-diary or as AEs in the CRF. Fever: defined as oral temperature \>=38 deg C and categorized as \>= 38.0-38.4 deg C, \>38.4-38.9 deg C, \>38.9-40.0 deg C and \>40.0 deg C. Fatigue, headache, chills, new or worsened muscle pain and joint pain: mild (didn't interfere with activity), moderate (some interference with activity), severe (prevented daily routine activity). Vomiting: mild: 1-2 times in 24h, moderate: \>2 times in 24h, severe: required IV hydration. Diarrhea: mild: 2-3 loose stools in 24h, moderate: 4-5 loose stools in 24h, severe: 6 or more loose stools in 24h. Grade 4 for all events except fever: ER visit/hospitalization. Grade 4 events were classified by investigator or medically qualified person.
Percentage of Participants With AEs From Vaccination Through 1 Month After Vaccination: SSC Cohort 3From vaccination on Day 1 up to 1 month after vaccinationAn AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with use of study intervention, whether or not considered related to study intervention. A SAE was defined as any untoward medical occurrence at any dose that resulted in any of the following outcomes: death; life-threatening; required inpatient hospitalization or prolongation of existing hospitalization; persistent or significant disability/incapacity; congenital anomaly/birth defect, any other event pre-specified in protocol of the study; or considered as an important medical event. AEs included both SAEs and all non-SAEs. Only AEs collected by non-systematic assessment (i.e., excluding local reactions and systemic events) were reported in this outcome measure.
Percentage of Participants With SAEs From Vaccination Through 6 Months After the Study Vaccination: SSC Cohort 3From vaccination on Day 1 up to 6 months after vaccinationAn AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. A SAE was defined as any untoward medical occurrence at any dose that resulted in any of the following outcomes: death; life-threatening; required inpatient hospitalization or prolongation of existing hospitalization; persistent or significant disability/incapacity; congenital anomaly/birth defect, any other event pre-specified in protocol of the study; or considered as an important medical event.
GMTs of SARS-CoV-2 Omi JN.1 and XBB.1.5 Variant-Neutralizing Titers at 1 Month After Vaccination in SSC Cohorts 1 + 2 Combined and Historical Control Group From SSAAt 1 month after vaccinationGMTs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ were set to 0.5\*LLOQ.
GMFR of SARS-CoV-2 Omi JN.1 and XBB.1.5 Variant-Neutralizing Titers From Before Vaccination to 1 Month After Vaccination in SSC Cohorts 1 + 2 Combined and Historical Control Group From SSAFrom before Vaccination to 1 month after VaccinationGMFRs were defined as geometric mean ratios of the results after vaccination to the results before vaccination. GMFRs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of fold rises and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ were set to 0.5\*LLOQ in the analysis.
Percentage of Participants With Seroresponse to SARS-CoV-2 OMI JN.1 and XBB.1.5 Variant-Neutralizing Titers at 1 Month After Vaccination in SSC Cohorts 1 + 2 Combined and Historical Control Group From SSAAt 1 month after vaccinationSeroresponse was defined as achieving a \>=4-fold rise from baseline (before the study vaccination). If the baseline measurement was below the LLOQ, a postvaccination assay result \>=4 \*LLOQ is considered a seroresponse.
GMTs of SARS-CoV-2 Omi KP.2 and Omi JN.1 Variant-Neutralizing Titers at 1 Month After Vaccination in SSC Cohort 3 and SSC Cohorts 1 + 2 Combined as ControlAt 1 month after vaccinationGMTs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ were set to 0.5\*LLOQ.
GMFR of SARS-CoV-2 Omi KP.2 and Omi JN.1 Variant-Neutralizing Titers From Before Vaccination to 1 Month After Vaccination in SSC Cohort 3 and Cohorts 1 + 2 Combined as ControlFrom before vaccination on Day 1 up to 1 month after vaccinationGMFRs were defined as geometric mean ratios of the results after vaccination to the results before vaccination. GMFRs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of fold rises and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ were set to 0.5\*LLOQ in the analysis.
Percentage of Participants With Seroresponse to SARS-CoV-2 Omi KP.2 and Omi JN.1 Variant-Neutralizing Titers at 1 Month After Vaccination in SSC Cohort 3 and Cohorts 1 + 2 Combined as ControlAt 1 month after vaccinationSeroresponse was defined as achieving a \>=4-fold rise from baseline (before the study vaccination). If the baseline measurement was below the LLOQ, a postvaccination assay result \>=4 \*LLOQ is considered a seroresponse.

Countries

United States

Contacts

STUDY_DIRECTORPfizer CT.gov Call Center

Pfizer

Participant flow

Recruitment details

In this study there were 3 sub-studies: sub-study A (SSA), sub-study B (SSB), and sub-study C (SSC).

Pre-assignment details

SSA: A total of 417 participants were assigned, out of which 412 were vaccinated. SSB: A total of 311 participants were assigned and vaccinated. SSC: A total of 321 participants were assigned, out of which 318 were vaccinated. As per study objectives, arms for SSC cohort 1 and 2 have been combined.

Baseline characteristics

Characteristic
Age, Customized
Age
12-17 Years
57 Participants
Age, Customized
Age
18-64 Years
723 Participants
Age, Customized
Age
65-84 Years
259 Participants
Age, Customized
Age
Greater than or equal to 85 Years
2 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
35 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
138 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
4 Participants
Race (NIH/OMB)
American Indian or Alaska Native
4 Participants
Race (NIH/OMB)
Asian
1 Participants
Race (NIH/OMB)
Black or African American
214 Participants
Race (NIH/OMB)
More than one race
5 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
3 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
White
746 Participants
Sex: Female, Male
Female
596 Participants
Sex: Female, Male
Male
11 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
EG004
affected / at risk
EG005
affected / at risk
EG006
affected / at risk
EG007
affected / at risk
EG008
affected / at risk
EG009
affected / at risk
EG010
affected / at risk
deaths
Total, all-cause mortality
0 / 300 / 1741 / 2080 / 90 / 2530 / 490 / 180 / 921 / 1060 / 510 / 51
other
Total, other adverse events
27 / 30154 / 174134 / 2084 / 9166 / 25325 / 4916 / 1877 / 9266 / 10643 / 5135 / 51
serious
Total, serious adverse events
1 / 300 / 1744 / 2080 / 92 / 2531 / 490 / 181 / 923 / 1060 / 511 / 51

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Apr 29, 2026