Influenza, HumanPhase 2NCT06237049

A Study to Learn About a Combined COVID-19 and Influenza Shot in Healthy Adults

A Phase 2 study testing BNT162b2 (Omi XBB.1.5)/RIV, BNT162b2 (Omi XBB.1.5) and RIV in people with Influenza, Human and SARS-CoV-2 Infection, run by Pfizer at 30 sites in United States.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record

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Trial summary

The purpose of this clinical trial is to see if combining a licensed COVID-19 vaccine and a licensed influenza vaccine into a single shot is safe and can help produce antibodies to defend the body against both SARS-CoV-2 (the virus that causes COVID-19) and influenza. Read more about this study

Who is it for?: Ages 50 years and olderHealthy volunteers can take part
Conditions the study is for: Influenza, Human, SARS-CoV-2 Infection, COVID-19
What is being tested?: BNT162b2 (Omi XBB.1.5)/RIV, BNT162b2 (Omi XBB.1.5) and RIV
Type of treatment: Vaccines, Injection or infusion
Could I receive a placebo?: Yes, some participants may receive a placebo
How many people: 644 participants
Where: 30 sitesUnited States
Study dates: 31 Jan 2024to 13 Sep 2024
Phase: Phase 2
Are there results?: Yes, posted in the registrySummary in the doctors' view

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

Ages 50 years and older
All sexes
Healthy volunteers accepted
Adult, Older adult

Who may be able to join

Male or female participants aged 50 years or older at Visit 1 (Day 1).
Participants who are willing and able to comply with all scheduled visits, the investigational plan, laboratory tests, lifestyle considerations, and other study procedures.
Healthy participants who are determined by medical history, physical examination (if required), and clinical judgment of the investigator to be eligible for inclusion in the study.
Capable of giving signed informed consent as described in the protocol, which includes compliance with the requirements and restrictions listed in the informed consent document (ICD) and in the protocol.

Who cannot join

Any medical or psychiatric condition including recent (within the past year) or active suicidal ideation/behavior or laboratory abnormality that may increase the risk of study participation or, in the investigator's judgment, make the participant inappropriate for the study.
Known infection with human immunodeficiency virus (HIV), hepatitis C virus (HCV), or hepatitis B virus (HBV).
History of severe adverse reaction associated with any vaccine and/or severe allergic reaction (eg, anaphylaxis) to any component of the study interventions.
Participants with a history of autoimmune disease or an active autoimmune disease requiring therapeutic intervention, including but not limited to systemic or cutaneous lupus erythematosus, autoimmune arthritis/rheumatoid arthritis, multiple sclerosis, Sjögren's syndrome, idiopathic thrombocytopenia purpura, glomerulonephritis, autoimmune thyroiditis, temporal arteritis, psoriasis, and/or insulin-dependent diabetes mellitus.
Immunocompromised individuals with known or suspected immunodeficiency, determined by history and/or laboratory/physical examination.
Current heart disease, uncontrolled hypertension, or a prior history of myocarditis or pericarditis.

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Bleeding diathesis or condition associated with prolonged bleeding that would, in the opinion of the investigator, contraindicate intramuscular injection.
Women who are pregnant, plan to become pregnant during the study, or are breastfeeding.
Prior history of ischemic stroke or transient ischemic attack.
Prior history of Guillain-Barré syndrome (GBS).
Participants with a calculated BMI of ≥35.
Receipt of chronic medications with known systemic immunosuppressant effects (including cytotoxic agents or systemic corticosteroids), or radiotherapy, within 60 days before enrollment 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 90 days before study intervention administration, or planned receipt throughout the study.
Vaccination with any investigational or licensed influenza vaccine within 6 months (180 days) before study intervention administration, or ongoing receipt of chronic antiviral therapy with activity against influenza.
Vaccination with any investigational or licensed COVID-19 vaccine within 6 months (180 days) before study intervention administration.
Participation in other studies involving administration of an investigational product within 28 days prior to, and/or during, participation in 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.
Deprived of freedom by an administrative or court order, or in an emergency setting, or hospitalized involuntarily.
Current alcohol abuse or drug addiction that in the opinion of the investigator might interfere with the study conduct or completion.

Trial locations and contacts

30 sites in 1 country.

City, postcode or hospital

30 sites in 1 country

United States30 sites

JEM Research Institute
Atlantis, Florida, 33462
Charlottesville Medical Research
Charlottesville, Virginia, 22911
Centricity Research Columbus Ohio Multispecialty
Columbus, Ohio, 43213
Indago Research & Health Center, Inc
Hialeah, Florida, 33012
East-West Medical Research Institute
Honolulu, Hawaii, 96814
DM Clinical Research- Cyfair
Houston, Texas, 77065
DM Clinical Research - Bellaire
Houston, Texas, 77081
Orange County Research Center
Lake Forest, California, 92630
Las Vegas Clinical Trials
Las Vegas, Nevada, 89030
Optimal Research
Melbourne, Florida, 32934
SMS Clinical Research
Mesquite, Texas, 75149
Clinical Research Consulting
Milford, Connecticut, 06460
Clinical Research Associates Inc
Nashville, Tennessee, 37203
Las Vegas Clinical Trials
North Las Vegas, Nevada, 89030
Headlands Research Orlando
Orlando, Florida, 32819
Optimal Research
Peoria, Illinois, 61614
ActivMed Practices & Research, LLC.
Portsmouth, New Hampshire, 03801
Rochester Clinical Research, LLC
Rochester, New York, 14609
Clinical Trials of Texas, LLC
San Antonio, Texas, 78229
IMA Clinical Research San Antonio
San Antonio, Texas, 78229
Bio-Kinetic Clinical Applications, LLC dba QPS-MO
Springfield, Missouri, 65802
Bio-Kinetic Clinical Applications, LLD dba QPS-MO
Springfield, Missouri, 65802
Bio-Kinetic Clinical Applications LLC DBA QPS-MO(Patient Screening Center)
Springfield, Missouri, 65807
Clinical Research Atlanta
Stockbridge, Georgia, 30281
DM Clinical Research - MDC
Tomball, Texas, 77375
Orange County Research Center
Tustin, California, 92780
Diablo Clinical Research, Inc.
Walnut Creek, California, 94598
GW Medical Faculty Associates
Washington D.C., District of Columbia, 20037
GW Vaccine Research Unit
Washington D.C., District of Columbia, 20037
Clinical Site Partners, LLC dba Flourish Research
Winter Park, Florida, 32789

Other trials in United States

About this study

Official title: A Phase 1/2 Randomized Study to Evaluate the Safety, Tolerability, and Immunogenicity of a Modified RNA COVID-19 Vaccine and a Recombinant Influenza Vaccine Administered as a Single Injection in Healthy Adults 50 Years of Age or Older

Read the detailed description

This is a Phase 1/2 study to evaluate the safety, tolerability, and immunogenicity of licensed BNT162b2 (Omi XBB.1.5) and recombinant influenza vaccine (RIV) administered together as a single injection (referred to as BNT162b2 [Omi XBB.1.5]/RIV) in healthy adults 50 years of age or older.

The safety, tolerability, and immunogenicity of BNT162b2 (OmiXBB1.5)/RIV administered as a single injection will be compared to BNT162b2 (Omi XBB.1.5) and RIV administered simultaneously as 2 separate injections (coadministered), and to BNT162b2 (Omi XBB.1.5) or RIV when administered alone.

Across Phases 1 and 2, approximately 640 participants in total will be randomized with an equal randomization ratio to 1 of 4 vaccine groups and stratified by age.

Conditions: Influenza, Human, SARS-CoV-2 Infection, COVID-19
Being tested: BNT162b2 (Omi XBB.1.5)/RIV, BNT162b2 (Omi XBB.1.5), RIV, Normal saline placebo
Keywords: Grippe, Flu, Influenza Vaccine, RNA Vaccine, COVID-19, Coronavirus Vaccine, SARS-CoV-2, mRNA Vaccine
Medical subject headings: Influenza, Human, COVID-19

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

BNT162b2 (Omi XBB.1.5)/RIVBiological
Combination of BNT162b2 (Omi XBB.1.5) and RIV
BNT162b2 (Omi XBB.1.5)Biological
Licensed COVID-19 vaccine
RIVBiological
Licensed recombinant influenza vaccine
Normal saline placeboOther
Normal saline (solution for injection)

Study groups in NCT06237049
Study group	Role	What they receive
BNT162b2 (Omi XBB.1.5)/RIV and placebo	Experimental	Participants will receive a single injection combination of BNT162b2 (Omi XBB.1.5) and RIV and normal saline placebo Receives: Biological: BNT162b2 (Omi XBB.1.5)/RIV; Other: Normal saline placebo
BNT162b2 (Omi XBB.1.5) and RIV	Experimental	Participants will receive BNT162b2 (Omi XBB.1.5) and RIV Receives: Biological: BNT162b2 (Omi XBB.1.5); Biological: RIV
BNT162b2 (Omi XBB.1.5) and placebo	Active comparator	Participants will receive BNT162b2 (Omi XBB.1.5) and normal saline placebo Receives: Biological: BNT162b2 (Omi XBB.1.5); Other: Normal saline placebo
RIV and placebo	Active comparator	Participants will receive RIV and normal saline placebo Receives: Biological: RIV; Other: Normal saline placebo

What is being measured

The primary outcome is the main question the study is designed to answer.

Percentage of Participants Who Reported Any Local Reaction up to 7 Days Following Vaccination
Local reactions included redness, swelling and pain at injection site, recorded by participants in an electronic diary (e-diary). Severity of all local reactions were evaluated as mild, moderate, severe or potentially life-threatening. In this outcome measure local reactions with any severity were reported for each left arm's deltoid and right arm's deltoid of each vaccine Group 1, 2, 3 and 4.
Measured: Day 1 to Day 7 following Vaccination on Day 1
Percentage of Participants Who Reported Any Systemic Events up to 7 Days Following Vaccination
Systemic events: fever, fatigue, headache, vomiting, diarrhea, chills, new/worsened muscle pain, new/worsened joint pain were recorded by participants in e-diary. Severity of all systemic events were evaluated as mild, moderate, severe or potentially life-threatening. In this outcome measure systemic events with any severity were reported.
Measured: Day 1 to Day 7 following Vaccination on Day 1
Percentage of Participants Who Reported Any Adverse Events (AEs) From Vaccination Through 4 Weeks After Vaccination
An AE was defined as any untoward medical occurrence in a participant temporally associated with the use of study intervention, whether or not considered related to the study intervention. Events collected by systematic assessment (local reactions and systemic events) were excluded from evaluation.
Measured: From Vaccination on Day 1 through 4 weeks after Vaccination
Percentage of Participants Who Reported Any Serious Adverse Events (SAEs) From Vaccination Through 6 Months After Vaccination
An 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. An SAE was defined as any untoward medical occurrence that, at any dose, met one or more of the following criteria - resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity, was a congenital anomaly/birth defect and other important medical events per protocol of the study. Events collected by systematic assessment (local reactions and systemic events) were excluded from evaluation.
Measured: From Vaccination on Day 1 through 6 months after Vaccination
Geometric Mean Titers (GMTs) of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Omicron (XBB.1.5)-Neutralizing Titers Before Vaccination
GMTs and the corresponding 2-sided CIs were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). As planned, outcome measure evaluated GMTs of SARS-CoV-2 Omicron (XBB.1.5), hence results are reported only for those reporting groups where BNT162b2 (Omi XBB.1.5) was administered. Data was not collected and not reported for reporting group "Group 4: RIV + Placebo", where BNT162b2 (Omi XBB.1.5) was not administered.
Measured: Before Vaccination on Day 1
GMTs of SARS-CoV-2 Omicron (XBB.1.5)-Neutralizing Titers at 4 Weeks After Vaccination
GMTs and the corresponding 2-sided CIs were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). As planned, outcome measure evaluated GMTs of SARS-CoV-2 Omicron (XBB.1.5), hence results are reported only for those reporting groups where BNT162b2 (Omi XBB.1.5) was administered. Data was not collected and not reported for reporting group "Group 4: RIV + Placebo", where BNT162b2 (Omi XBB.1.5) was not administered.
Measured: At 4 weeks after Vaccination on Day 1
Geometric Mean Fold Rise (GMFR) of SARS-CoV-2 Omicron (XBB.1.5)-Neutralizing Titers From Before Vaccination to 4 Weeks After Vaccination
GMFR was the ratio of the geometric mean titre values 4 weeks after vaccination to before vaccination. GMFRs and the corresponding 2-sided CIs were calculated by exponentiating the mean logarithm of fold rises and the corresponding CIs (based on the Student t distribution). As planned, outcome measure evaluated GMTs of SARS-CoV-2 Omicron (XBB.1.5), hence results are reported only for those reporting groups where BNT162b2 (Omi XBB.1.5) was administered. Data was not collected and not reported for reporting group "Group 4: RIV + Placebo", where BNT162b2 (Omi XBB.1.5) was not administered.
Measured: From before Vaccination on Day 1 to 4 weeks after Vaccination
Percentages of Participants With Seroresponse to SARS-CoV-2 Omicron (XBB.1.5) at 4 Weeks After Vaccination
Seroresponse was defined as achieving a >=4-fold rise from baseline (before the study vaccination). If the baseline measurement was below the lower limit of quantification (LLOQ), the postvaccination measure of >=4*LLOQ is considered a seroresponse. Exact 2-sided CI, based on the Clopper and Pearson method. As planned, outcome measure evaluated GMTs of SARS-CoV-2 Omicron (XBB.1.5), hence results are reported only for those reporting groups where BNT162b2 (Omi XBB.1.5) was administered. Data was not collected and not reported for reporting group "Group 4: RIV + Placebo", where BNT162b2 (Omi XBB.1.5) was not administered.
Measured: At 4 weeks after Vaccination on Day 1
GMTs of Strain Specific Hemagglutinin Inhibition Assay (HAI) Titers Before Vaccination
GMTs and the corresponding 2-sided CIs were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). The 4 virus strains which were evaluated and reported in this outcome measure were A/Victoria/4897/2022 (H1N1) HAI, A/Darwin/9/2021 (H3N2) HAI, B/Michigan/1/2021 HAI and B/Phuket/3073/2013 HAI. As planned, outcome measure evaluated GMTs of strain specific HAI, hence results are reported only for those reporting groups where RIV was administered. Data was not collected and not reported for reporting group "Group 3: BNT162b2 (Omi XBB.1.5) + Placebo", where RIV was not administered.
Measured: Before Vaccination on Day 1
GMTs of Strain Specific Hemagglutinin Inhibition Assay (HAI) Titers at 4 Weeks After Vaccination
GMTs and the corresponding 2-sided CIs were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). The 4 virus strains which were evaluated and reported in this outcome measure were A/Victoria/4897/2022 (H1N1) HAI, A/Darwin/9/2021 (H3N2) HAI, B/Michigan/1/2021 HAI and B/Phuket/3073/2013 HAI. As planned, outcome measure evaluated GMTs of strain specific HAI, hence results are reported only for those reporting groups where RIV was administered. Data was not collected and not reported for reporting group "Group 3: BNT162b2 (Omi XBB.1.5) + Placebo", where RIV was not administered.
Measured: At 4 weeks after Vaccination on Day 1
GMFR of Strain Specific HAI Titers From Before Vaccination to 4 Weeks After Vaccination
GMFR was the ratio of the geometric mean titre values 4 weeks after vaccination to before vaccination. GMFRs and the corresponding 2-sided CIs were calculated by exponentiating the mean logarithm of fold rises and the corresponding CIs (based on the Student t distribution). The 4 virus strains which were evaluated and reported in this outcome measure were A/Victoria/4897/2022 (H1N1) HAI, A/Darwin/9/2021 (H3N2) HAI, B/Michigan/1/2021 HAI and B/Phuket/3073/2013 HAI. As planned, outcome measure evaluated GMFRs of strain specific HAI, hence results are reported only for those reporting groups where RIV was administered. Data was not collected and not reported for reporting group "Group 3: BNT162b2 (Omi XBB.1.5) + Placebo", where RIV was not administered.
Measured: From before Vaccination to 4 weeks after Vaccination on Day 1
Percentages of Participants Achieving HAI Seroconversion at 4 Weeks After Vaccination
Seroconversion was defined as an HAI titer <1:10 prior to vaccination and >=1:40 at the time point of interest, or an HAI titer of >=1:10 prior to vaccination with a minimum 4-fold rise at the time point of interest. Exact 2-sided CI, based on the Clopper and Pearson method. The 4 virus strains which were evaluated and reported in this outcome measure were A/Victoria/4897/2022 (H1N1) HAI, A/Darwin/9/2021 (H3N2) HAI, B/Michigan/1/2021 HAI and B/Phuket/3073/2013 HAI. As planned, outcome measure evaluated seroconversion of strain specific HAI, hence results are reported only for those reporting groups where RIV was administered. Data was not collected and not reported for reporting group "Group 3: BNT162b2 (Omi XBB.1.5) + Placebo", where RIV was not administered.
Measured: At 4 weeks after Vaccination on Day 1
Percentages of Participants With HAI Titers >= 1:40 Before Vaccination
Percentages of participants with HAI titers >= 1:40 before vaccination along with the associated 2-sided 95% CIs, was provided for each vaccine group in this outcome measure. Exact 2-sided CI, based on the Clopper and Pearson method. The 4 virus strains which were evaluated and reported in this outcome measure were A/Victoria/4897/2022 (H1N1) HAI, A/Darwin/9/2021 (H3N2) HAI, B/Michigan/1/2021 HAI and B/Phuket/3073/2013 HAI. As planned, outcome measure evaluated of strain specific HAI, hence results are reported only for those reporting groups where RIV was administered. Data was not collected and not reported for reporting group "Group 3: BNT162b2 (Omi XBB.1.5) + Placebo", where RIV was not administered.
Measured: Before Vaccination on Day 1
Percentages of Participants With HAI Titers >= 1:40 at 4 Weeks After Vaccination
Percentages of participants with HAI titers >= 1:40 at 4 weeks after vaccination along with the associated 2-sided 95% CIs, was provided for each vaccine group in this outcome measure. Exact 2-sided CI, based on the Clopper and Pearson method. The 4 virus strains which were evaluated and reported in this outcome measure were A/Victoria/4897/2022 (H1N1) HAI, A/Darwin/9/2021 (H3N2) HAI, B/Michigan/1/2021 HAI and B/Phuket/3073/2013 HAI. As outcome measure evaluated of strain specific HAI, hence results are reported only for those reporting groups where RIV was administered. Data was not collected and not reported for reporting group "Group 3: BNT162b2 (Omi XBB.1.5) + Placebo", where RIV was not administered.
Measured: At 4 Weeks after Vaccination on Day 1

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

31 Jan 202413 Sep 2024

First posted1 Feb 2024
Study start31 Jan 2024
Primary completion13 Sep 2024
Study completion13 Sep 2024

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
Other trials for Influenza, HumanStudies of the same condition, open and under way.
More trials run by PfizerThe sponsor's other registered studies.
What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design

Study type: Interventional
Phase: Phase 2
Primary purpose: Prevention
Allocation: Randomised
Intervention model: Parallel groups
Masking: Single blind
Who is masked: Participant
Enrolment: 644 participants (actual)

IDs, dates and publications

ClinicalTrials.gov ID: NCT06237049
Sponsor's protocol ID: C5681001
Status last verified: Sep 2025
First submitted: 30 Jan 2024
Last updated: 30 Sep 2025
Results posted: Yes, on ClinicalTrials.gov
Data monitoring committee: No
FDA-regulated drug: Yes
FDA-regulated device: No
Individual data sharing: Yes: Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical\_trials/trial\_data\_and\_results/data\_requests.

Want to know more?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

See locations

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Post Influenza

All Influenza, Human trials

Study at a glance

From the registry record, last updated by the sponsor on 30 Sep 2025. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: A Phase 1/2 Randomized Study to Evaluate the Safety, Tolerability, and Immunogenicity of a Modified RNA COVID-19 Vaccine and a Recombinant Influenza Vaccine Administered as a Single Injection in Healthy Adults 50 Years of Age or Older
ClinicalTrials.gov ID: NCT06237049
Acronym / sponsor ID: C5681001
Conditions: Influenza, Human, SARS-CoV-2 Infection, COVID-19
Keywords: Grippe, Flu, Influenza Vaccine, RNA Vaccine, COVID-19, Coronavirus Vaccine, SARS-CoV-2, mRNA Vaccine
Phase: Phase 2
Study type: Interventional
Recruitment status: Completed
Enrolment: 644 participants (actual)
Lead sponsor: PfizerIndustry (pharma, biotech, devices)
Study start: 31 Jan 2024 (actual)
Primary completion: 13 Sep 2024 (actual)
Study completion: 13 Sep 2024 (actual)
First posted: 1 Feb 2024 (actual)
Results: Posted 30 Sep 2025

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

Detailed description

Across Phases 1 and 2, approximately 640 participants in total will be randomized with an equal randomization ratio to 1 of 4 vaccine groups and stratified by age.

Study design

Primary purpose: Prevention
Allocation: Randomised
Intervention model: Parallel groups
Masking: Single blind (participant)
Number of arms: 4

Arm	Type	Receives
BNT162b2 (Omi XBB.1.5)/RIV and placebo	Experimental	Biological: BNT162b2 (Omi XBB.1.5)/RIV, Other: Normal saline placeboParticipants will receive a single injection combination of BNT162b2 (Omi XBB.1.5) and RIV and normal saline placebo
BNT162b2 (Omi XBB.1.5) and RIV	Experimental	Biological: BNT162b2 (Omi XBB.1.5), Biological: RIVParticipants will receive BNT162b2 (Omi XBB.1.5) and RIV
BNT162b2 (Omi XBB.1.5) and placebo	Active comparator	Biological: BNT162b2 (Omi XBB.1.5), Other: Normal saline placeboParticipants will receive BNT162b2 (Omi XBB.1.5) and normal saline placebo
RIV and placebo	Active comparator	Biological: RIV, Other: Normal saline placeboParticipants will receive RIV and normal saline placebo

Who may qualify

Ages: 50 years and older
Sex: All
Healthy volunteers: Accepted
Age groups: Adult, Older adult

Key inclusion criteria (4 listed)

Male or female participants aged 50 years or older at Visit 1 (Day 1).
Participants who are willing and able to comply with all scheduled visits, the investigational plan, laboratory tests, lifestyle considerations, and other study procedures.
Healthy participants who are determined by medical history, physical examination (if required), and clinical judgment of the investigator to be eligible for inclusion in the study.
Capable of giving signed informed consent as described in the protocol, which includes compliance with the requirements and restrictions listed in the informed consent document (ICD) and in the protocol.

Key exclusion criteria (19 listed)

Any medical or psychiatric condition including recent (within the past year) or active suicidal ideation/behavior or laboratory abnormality that may increase the risk of study participation or, in the investigator's judgment, make the participant inappropriate for the study.
Known infection with human immunodeficiency virus (HIV), hepatitis C virus (HCV), or hepatitis B virus (HBV).
History of severe adverse reaction associated with any vaccine and/or severe allergic reaction (eg, anaphylaxis) to any component of the study interventions.
Participants with a history of autoimmune disease or an active autoimmune disease requiring therapeutic intervention, including but not limited to systemic or cutaneous lupus erythematosus, autoimmune arthritis/rheumatoid arthritis, multiple sclerosis, Sjögren's syndrome, idiopathic thrombocytopenia purpura, glomerulonephritis, autoimmune thyroiditis, temporal arteritis, psoriasis, and/or insulin-dependent diabetes mellitus.
Immunocompromised individuals with known or suspected immunodeficiency, determined by history and/or laboratory/physical examination.

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
BNT162b2 (Omi XBB.1.5)/RIVCombination of BNT162b2 (Omi XBB.1.5) and RIV	Biological	BNT162b2 (Omi XBB.1.5)/RIV and placebo
BNT162b2 (Omi XBB.1.5)Licensed COVID-19 vaccine	Biological	BNT162b2 (Omi XBB.1.5) and RIV, BNT162b2 (Omi XBB.1.5) and placebo
RIVLicensed recombinant influenza vaccine	Biological	BNT162b2 (Omi XBB.1.5) and RIV, RIV and placebo
Normal saline placeboNormal saline (solution for injection)	Other	BNT162b2 (Omi XBB.1.5) and placebo, BNT162b2 (Omi XBB.1.5)/RIV and placebo, RIV and placebo

Primary outcome

Percentage of Participants Who Reported Any Local Reaction up to 7 Days Following Vaccination
Time frame: Day 1 to Day 7 following Vaccination on Day 1
Local reactions included redness, swelling and pain at injection site, recorded by participants in an electronic diary (e-diary). Severity of all local reactions were evaluated as mild, moderate, severe or potentially life-threatening. In this outcome measure local reactions with any severity were reported for each left arm's deltoid and right arm's deltoid of each vaccine Group 1, 2, 3 and 4.
Percentage of Participants Who Reported Any Systemic Events up to 7 Days Following Vaccination
Time frame: Day 1 to Day 7 following Vaccination on Day 1
Systemic events: fever, fatigue, headache, vomiting, diarrhea, chills, new/worsened muscle pain, new/worsened joint pain were recorded by participants in e-diary. Severity of all systemic events were evaluated as mild, moderate, severe or potentially life-threatening. In this outcome measure systemic events with any severity were reported.
Percentage of Participants Who Reported Any Adverse Events (AEs) From Vaccination Through 4 Weeks After Vaccination
Time frame: From Vaccination on Day 1 through 4 weeks after Vaccination
An AE was defined as any untoward medical occurrence in a participant temporally associated with the use of study intervention, whether or not considered related to the study intervention. Events collected by systematic assessment (local reactions and systemic events) were excluded from evaluation.
Percentage of Participants Who Reported Any Serious Adverse Events (SAEs) From Vaccination Through 6 Months After Vaccination
Time frame: From Vaccination on Day 1 through 6 months after Vaccination
An 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. An SAE was defined as any untoward medical occurrence that, at any dose, met one or more of the following criteria - resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity, was a congenital anomaly/birth defect and other important medical events per protocol of the study. Events collected by systematic assessment (local reactions and systemic events) were excluded from evaluation.
Geometric Mean Titers (GMTs) of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Omicron (XBB.1.5)-Neutralizing Titers Before Vaccination
Time frame: Before Vaccination on Day 1
GMTs and the corresponding 2-sided CIs were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). As planned, outcome measure evaluated GMTs of SARS-CoV-2 Omicron (XBB.1.5), hence results are reported only for those reporting groups where BNT162b2 (Omi XBB.1.5) was administered. Data was not collected and not reported for reporting group "Group 4: RIV + Placebo", where BNT162b2 (Omi XBB.1.5) was not administered.
GMTs of SARS-CoV-2 Omicron (XBB.1.5)-Neutralizing Titers at 4 Weeks After Vaccination
Time frame: At 4 weeks after Vaccination on Day 1
GMTs and the corresponding 2-sided CIs were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). As planned, outcome measure evaluated GMTs of SARS-CoV-2 Omicron (XBB.1.5), hence results are reported only for those reporting groups where BNT162b2 (Omi XBB.1.5) was administered. Data was not collected and not reported for reporting group "Group 4: RIV + Placebo", where BNT162b2 (Omi XBB.1.5) was not administered.
Geometric Mean Fold Rise (GMFR) of SARS-CoV-2 Omicron (XBB.1.5)-Neutralizing Titers From Before Vaccination to 4 Weeks After Vaccination
Time frame: From before Vaccination on Day 1 to 4 weeks after Vaccination
GMFR was the ratio of the geometric mean titre values 4 weeks after vaccination to before vaccination. GMFRs and the corresponding 2-sided CIs were calculated by exponentiating the mean logarithm of fold rises and the corresponding CIs (based on the Student t distribution). As planned, outcome measure evaluated GMTs of SARS-CoV-2 Omicron (XBB.1.5), hence results are reported only for those reporting groups where BNT162b2 (Omi XBB.1.5) was administered. Data was not collected and not reported for reporting group "Group 4: RIV + Placebo", where BNT162b2 (Omi XBB.1.5) was not administered.
Percentages of Participants With Seroresponse to SARS-CoV-2 Omicron (XBB.1.5) at 4 Weeks After Vaccination
Time frame: At 4 weeks after Vaccination on Day 1
Seroresponse was defined as achieving a >=4-fold rise from baseline (before the study vaccination). If the baseline measurement was below the lower limit of quantification (LLOQ), the postvaccination measure of >=4*LLOQ is considered a seroresponse. Exact 2-sided CI, based on the Clopper and Pearson method. As planned, outcome measure evaluated GMTs of SARS-CoV-2 Omicron (XBB.1.5), hence results are reported only for those reporting groups where BNT162b2 (Omi XBB.1.5) was administered. Data was not collected and not reported for reporting group "Group 4: RIV + Placebo", where BNT162b2 (Omi XBB.1.5) was not administered.
GMTs of Strain Specific Hemagglutinin Inhibition Assay (HAI) Titers Before Vaccination
Time frame: Before Vaccination on Day 1
GMTs and the corresponding 2-sided CIs were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). The 4 virus strains which were evaluated and reported in this outcome measure were A/Victoria/4897/2022 (H1N1) HAI, A/Darwin/9/2021 (H3N2) HAI, B/Michigan/1/2021 HAI and B/Phuket/3073/2013 HAI. As planned, outcome measure evaluated GMTs of strain specific HAI, hence results are reported only for those reporting groups where RIV was administered. Data was not collected and not reported for reporting group "Group 3: BNT162b2 (Omi XBB.1.5) + Placebo", where RIV was not administered.
GMTs of Strain Specific Hemagglutinin Inhibition Assay (HAI) Titers at 4 Weeks After Vaccination
Time frame: At 4 weeks after Vaccination on Day 1
GMTs and the corresponding 2-sided CIs were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). The 4 virus strains which were evaluated and reported in this outcome measure were A/Victoria/4897/2022 (H1N1) HAI, A/Darwin/9/2021 (H3N2) HAI, B/Michigan/1/2021 HAI and B/Phuket/3073/2013 HAI. As planned, outcome measure evaluated GMTs of strain specific HAI, hence results are reported only for those reporting groups where RIV was administered. Data was not collected and not reported for reporting group "Group 3: BNT162b2 (Omi XBB.1.5) + Placebo", where RIV was not administered.
GMFR of Strain Specific HAI Titers From Before Vaccination to 4 Weeks After Vaccination
Time frame: From before Vaccination to 4 weeks after Vaccination on Day 1
GMFR was the ratio of the geometric mean titre values 4 weeks after vaccination to before vaccination. GMFRs and the corresponding 2-sided CIs were calculated by exponentiating the mean logarithm of fold rises and the corresponding CIs (based on the Student t distribution). The 4 virus strains which were evaluated and reported in this outcome measure were A/Victoria/4897/2022 (H1N1) HAI, A/Darwin/9/2021 (H3N2) HAI, B/Michigan/1/2021 HAI and B/Phuket/3073/2013 HAI. As planned, outcome measure evaluated GMFRs of strain specific HAI, hence results are reported only for those reporting groups where RIV was administered. Data was not collected and not reported for reporting group "Group 3: BNT162b2 (Omi XBB.1.5) + Placebo", where RIV was not administered.
Percentages of Participants Achieving HAI Seroconversion at 4 Weeks After Vaccination
Time frame: At 4 weeks after Vaccination on Day 1
Seroconversion was defined as an HAI titer <1:10 prior to vaccination and >=1:40 at the time point of interest, or an HAI titer of >=1:10 prior to vaccination with a minimum 4-fold rise at the time point of interest. Exact 2-sided CI, based on the Clopper and Pearson method. The 4 virus strains which were evaluated and reported in this outcome measure were A/Victoria/4897/2022 (H1N1) HAI, A/Darwin/9/2021 (H3N2) HAI, B/Michigan/1/2021 HAI and B/Phuket/3073/2013 HAI. As planned, outcome measure evaluated seroconversion of strain specific HAI, hence results are reported only for those reporting groups where RIV was administered. Data was not collected and not reported for reporting group "Group 3: BNT162b2 (Omi XBB.1.5) + Placebo", where RIV was not administered.
Percentages of Participants With HAI Titers >= 1:40 Before Vaccination
Time frame: Before Vaccination on Day 1
Percentages of participants with HAI titers >= 1:40 before vaccination along with the associated 2-sided 95% CIs, was provided for each vaccine group in this outcome measure. Exact 2-sided CI, based on the Clopper and Pearson method. The 4 virus strains which were evaluated and reported in this outcome measure were A/Victoria/4897/2022 (H1N1) HAI, A/Darwin/9/2021 (H3N2) HAI, B/Michigan/1/2021 HAI and B/Phuket/3073/2013 HAI. As planned, outcome measure evaluated of strain specific HAI, hence results are reported only for those reporting groups where RIV was administered. Data was not collected and not reported for reporting group "Group 3: BNT162b2 (Omi XBB.1.5) + Placebo", where RIV was not administered.
Percentages of Participants With HAI Titers >= 1:40 at 4 Weeks After Vaccination
Time frame: At 4 Weeks after Vaccination on Day 1
Percentages of participants with HAI titers >= 1:40 at 4 weeks after vaccination along with the associated 2-sided 95% CIs, was provided for each vaccine group in this outcome measure. Exact 2-sided CI, based on the Clopper and Pearson method. The 4 virus strains which were evaluated and reported in this outcome measure were A/Victoria/4897/2022 (H1N1) HAI, A/Darwin/9/2021 (H3N2) HAI, B/Michigan/1/2021 HAI and B/Phuket/3073/2013 HAI. As outcome measure evaluated of strain specific HAI, hence results are reported only for those reporting groups where RIV was administered. Data was not collected and not reported for reporting group "Group 3: BNT162b2 (Omi XBB.1.5) + Placebo", where RIV was not administered.

Results and safety

Results posted to the registry on 30 Sep 2025, as reported by the sponsor. Figures are copied from the record, not re-analysed. Full results on ClinicalTrials.gov.

Participant flow

Group	Started	Completed
Group 1: BNT162b2 (Omi XBB.1.5)/ RIV + Placebo	160	145
Group 2: BNT162b2 (Omi XBB.1.5) + RIV	163	155
Group 3: BNT162b2 (Omi XBB.1.5) + Placebo	160	151
Group 4: RIV + Placebo	161	151

Primary outcome: Percentage of Participants Who Reported Any Local Reaction up to 7 Days Following Vaccination

Time frame: Day 1 to Day 7 following Vaccination on Day 1. Number (95% Confidence Interval). Unit: Percentage of participants

Measure	Group 1, BNT162b2/RIV + Placebo: BNT162b2/RIV n = 160	Group 1, BNT162b2/RIV + Placebo: Placebo n = 160	Group 2, BNT162b2 + RIV: BNT162b2 n = 161	Group 2, BNT162b2 + RIV: RIV n = 161	Group 3, BNT162b2 + Placebo: BNT162b2 n = 160	Group 3, BNT162b2 + Placebo: Placebo n = 160	Group 4, RIV + Placebo: RIV n = 160	Group 4, RIV + Placebo: Placebo n = 160
Pain at injection site	56.3 (48.2 to 64.1)	11.9 (7.3 to 17.9)	59.0 (51.0 to 66.7)	38.5 (31.0 to 46.5)	62.5 (54.5 to 70.0)	9.4 (5.3 to 15.0)	36.9 (29.4 to 44.9)	8.1 (4.4 to 13.5)
Redness	8.8 (4.9 to 14.2)	1.3 (0.2 to 4.4)	5.0 (2.2 to 9.6)	3.1 (1.0 to 7.1)	5.0 (2.2 to 9.6)	0.6 (0.0 to 3.4)	6.3 (3.0 to 11.2)	0.6 (0.0 to 3.4)
Swelling	9.4 (5.3 to 15.0)	1.3 (0.2 to 4.4)	6.2 (3.0 to 11.1)	3.1 (1.0 to 7.1)	5.6 (2.6 to 10.4)	0.6 (0.0 to 3.4)	5.0 (2.2 to 9.6)	0.6 (0.0 to 3.4)

Population analysed: SAS consisted of all participants who received at least 1 dose of the study intervention. As planned, results of this outcome measure are reported for vaccination in each arm (left and right deltoid- as separate reporting arm) of each vaccine group.

Primary outcome: Percentage of Participants Who Reported Any Systemic Events up to 7 Days Following Vaccination

Time frame: Day 1 to Day 7 following Vaccination on Day 1. Number (95% Confidence Interval). Unit: Percentage of participants

Measure	Group 1: BNT162b2 (Omi XBB.1.5)/ RIV + Placebo n = 160	Group 2: BNT162b2 (Omi XBB.1.5) + RIV n = 161	Group 3: BNT162b2 (Omi XBB.1.5) + Placebo n = 160	Group 4: RIV + Placebo n = 160
Fever	1.9 (0.4 to 5.4)	6.2 (3.0 to 11.1)	6.3 (3.0 to 11.2)	0 (0.0 to 2.3)
Fatigue	36.3 (28.8 to 44.2)	39.1 (31.5 to 47.1)	40.6 (32.9 to 48.7)	33.1 (25.9 to 41.0)
Headache	24.4 (17.9 to 31.8)	31.1 (24.0 to 38.8)	26.9 (20.2 to 34.4)	16.9 (11.4 to 23.6)
Vomiting	0 (0.0 to 2.3)	3.1 (1.0 to 7.1)	1.9 (0.4 to 5.4)	0 (0.0 to 2.3)
Diarrhea	8.1 (4.4 to 13.5)	11.2 (6.8 to 17.1)	11.3 (6.8 to 17.2)	7.5 (3.9 to 12.7)
Chills	8.8 (4.9 to 14.2)	14.9 (9.8 to 21.4)	15.0 (9.9 to 21.5)	6.9 (3.5 to 12.0)
New or worsened muscle pain	13.1 (8.3 to 19.4)	22.4 (16.2 to 29.6)	15.0 (9.9 to 21.5)	8.1 (4.4 to 13.5)
New or worsened joint pain	7.5 (3.9 to 12.7)	13.7 (8.8 to 20.0)	10.0 (5.8 to 15.7)	4.4 (1.8 to 8.8)

Population analysed: SAS consisted of all participants who received at least 1 dose of the study intervention. Data is presented for each vaccine group.

Primary outcome: Percentage of Participants Who Reported Any Adverse Events (AEs) From Vaccination Through 4 Weeks After Vaccination

Time frame: From Vaccination on Day 1 through 4 weeks after Vaccination. Number (95% Confidence Interval). Unit: Percentage of participants

Measure	Group 1: BNT162b2 (Omi XBB.1.5)/ RIV + Placebo n = 160	Group 2: BNT162b2 (Omi XBB.1.5) + RIV n = 161	Group 3: BNT162b2 (Omi XBB.1.5) + Placebo n = 160	Group 4: RIV + Placebo n = 160
Value	4.4 (1.8 to 8.8)	3.7 (1.4 to 7.9)	5.6 (2.6 to 10.4)	5.6 (2.6 to 10.4)

Population analysed: SAS consisted of all participants who received at least 1 dose of the study intervention. Data is presented for each vaccine group.

Primary outcome: Percentage of Participants Who Reported Any Serious Adverse Events (SAEs) From Vaccination Through 6 Months After Vaccination

Time frame: From Vaccination on Day 1 through 6 months after Vaccination. Number (95% Confidence Interval). Unit: Percentage of participants

Measure	Group 1: BNT162b2 (Omi XBB.1.5)/ RIV + Placebo n = 160	Group 2: BNT162b2 (Omi XBB.1.5) + RIV n = 161	Group 3: BNT162b2 (Omi XBB.1.5) + Placebo n = 160	Group 4: RIV + Placebo n = 160
Value	1.9 (0.4 to 5.4)	0.6 (0.0 to 3.4)	0 (0.0 to 2.3)	1.9 (0.4 to 5.4)

Population analysed: SAS consisted of all participants who received at least 1 dose of the study intervention. Data is presented for each vaccine group.

Adverse events

Time frame: AEs by systematic assessment: Day 1 up to 7 Days following Vaccination; AEs by Non-systematic assessment: a) Serious AEs- Day 1 of Vaccination up to 6 months of follow-up after Vaccination, b) Other AEs- Day 1 of Vaccination up to 4 weeks of follow-up after Vaccination; All-cause mortality: Day 1 of Vaccination up to 6 months of follow-up after Vaccination. Other adverse events reported at 0% frequency or more

Group	Serious adverse events	Other adverse events	Deaths
Group 1: BNT162b2 (Omi XBB.1.5)/ RIV + Placebo	3 of 160 (1.9%)	114 of 160 (71.3%)	0 of 160
Group 2: BNT162b2 (Omi XBB.1.5) + RIV	1 of 161 (0.6%)	117 of 161 (72.7%)	0 of 161
Group 3: BNT162b2 (Omi XBB.1.5) + Placebo	0 of 160 (0%)	115 of 160 (71.9%)	0 of 160
Group 4: RIV + Placebo	3 of 160 (1.9%)	88 of 160 (55%)	1 of 160

Loading the posted results from ClinicalTrials.gov…

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 30 Sep 2025.
Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
To obtain contact information for a study center near you, click here.Link provided by the sponsor.
Individual participant dataSharing planned: Yes. Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical_trials/trial_data_and_results/data_requests.

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Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.

Pfizer CT.gov Call Center study director

Pfizer

30 sites in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

A Phase 2 study testing BNT162b2 (Omi XBB.1.5)/RIV, BNT162b2 (Omi XBB.1.5) and RIV in people with Influenza, Human and SARS-CoV-2 Infection, run by Pfizer at 30 sites in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 4 inclusion and 19 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 30 Sep 2025. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 30 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

Yes. Results are posted in the registry (first posted 30 Sep 2025). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Percentage of Participants Who Reported Any Local Reaction up to 7 Days Following Vaccination (time frame: Day 1 to Day 7 following Vaccination on Day 1). The study lists 14 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT06237049.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 30 Sep 2025.