Safety and Immunogenicity of BNT162b2 Coadministered With SIIV in Adults 18 Through 64 Years of Age
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ClinicalTrials.gov Identifier: NCT05310084 |
Recruitment Status :
Recruiting
First Posted : April 4, 2022
Last Update Posted : June 21, 2022
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This study will assess the safety and immunogenicity of a fourth dose (booster) of BNT162b2 when coadministered with SIIV compared to separate administration of the vaccines when given 1 month apart (SIIV followed by BNT162b2), in participants who have received 3 prior doses of 30 µg BNT162b2, with the third dose being at least 90 days before Visit 1 (Day 1).
- Healthy adults 18 through 64 years of age will be randomized 1:1 to either the co-administration group, or the separate administration group
- The duration of the study for each participant will be approximately 2 months
- There are 3 scheduled study visits each about 1 month apart
- The study will be conducted in New Zealand and Australia.
Condition or disease | Intervention/treatment | Phase |
---|---|---|
SARS-CoV-2 Infection COVID-19 | Biological: BNT162b2 Other: Placebo Biological: Seasonal Inactivated Influenza Vaccine | Phase 3 |
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 1126 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor) |
Masking Description: | This is an Observer-Blind Study. The vaccines and placebo will be administered by an unblinded third-party site staff member. |
Primary Purpose: | Prevention |
Official Title: | A PHASE 3, RANDOMIZED, OBSERVER-BLIND TRIAL TO EVALUATE THE SAFETY AND IMMUNOGENICITY OF BNT162b2 WHEN COADMINISTERED WITH SEASONAL INACTIVATED INFLUENZA VACCINE (SIIV) IN ADULTS 18 THROUGH 64 YEARS OF AGE |
Actual Study Start Date : | April 20, 2022 |
Estimated Primary Completion Date : | September 21, 2022 |
Estimated Study Completion Date : | September 21, 2022 |

Arm | Intervention/treatment |
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Experimental: Coadministration Group
BNT162b2 and SIIV followed by placebo a month later
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Biological: BNT162b2
Intramuscular injection Other: Placebo Saline intramuscular injection Biological: Seasonal Inactivated Influenza Vaccine SIIV intramuscular injection |
Experimental: Separate Administration Group
Placebo and SIIV followed by BNT162b2 a month later
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Biological: BNT162b2
Intramuscular injection Other: Placebo Saline intramuscular injection Biological: Seasonal Inactivated Influenza Vaccine SIIV intramuscular injection |
- Local reactions (redness, swelling, and pain at the injection site) self-reported on e-diaries [ Time Frame: 7 days after each vaccination ]The percentage of participants reporting prompted local reactions within 7 days after each vaccination
- Systemic events (fever, fatigue, headache, chills, vomiting, diarrhea, new or worsened muscle pain, and new or worsened joint pain) self-reported on e-diaries [ Time Frame: 7 days after each vaccination ]The percentage of participants reporting prompted systemic events within 7 days after each vaccination
- Adverse Events [ Time Frame: 1 month after each vaccination ]The percentage of participants reporting AEs within 1 month after each vaccination
- Serious Adverse Events [ Time Frame: 1 month after the last vaccination ]The percentage of participants reporting SAEs from the first vaccination up to 1 month after the last vaccination
- Full-length S-binding IgG levels [ Time Frame: 1 month after vaccination with BNT162b2 ]Geometric mean ratio of full-length S-binding IgG levels 1 month after vaccination with BNT162b2 in the coadministration group to the IgG levels 1 month after vaccination with BNT162b2 in the separate administration group
- Strain-specific HAI titers ; H3N2-neutralizing antibody titers (if H3N2-HAI titers cannot be obtained) [ Time Frame: 1 month after vaccination with SIIV ]Geometric mean ratio of the strain-specific HAI (or H3N2-neutralizing antibody) titers 1 month after vaccination with SIIV in the coadministration group to the corresponding HAI (or H3N2-neutralizing antibody) titers in the separate administration group
- Full-length S-binding IgG levels ; SARS-CoV-2 neutralizing titers (for a subset of approximately 200 participants) expressed as Geometric Mean Concentrations/Geometric Mean Titers [ Time Frame: At baseline (before vaccination) and 1 month after vaccination with BNT162b2 ]Geometric Mean Concentrations/Geometric Mean Titers elicited by BNT162b2 when coadministered with SIIV or administered alone
- Full-length S-binding IgG levels ; SARS-CoV-2 neutralizing titers (for a subset of approximately 200 participants) expressed as Geometric Mean Fold Rise [ Time Frame: At baseline (before vaccination) and 1 month after vaccination with BNT162b2 ]Geometric Mean Fold Rise elicited by BNT162b2 when coadministered with SIIV or administered alone
- Strain-specific HAI titers ; H3N2-neutralizing antibody titers (if H3N2-HAI titers cannot be obtained) expressed as Geometric Mean Titers [ Time Frame: At baseline (before vaccination) and 1 month after vaccination with SIIV ]Geometric Mean Titers elicited by SIIV when coadministered with BNT162b2 or administered alone
- Strain-specific HAI titers ; H3N2-neutralizing antibody titers (if H3N2-HAI titers cannot be obtained) expressed as Geometric Mean Fold Rise [ Time Frame: At baseline (before vaccination) and 1 month after vaccination with SIIV ]Geometric Mean Fold Rise in strain-specific HAI titers elicited by SIIV when coadministered with BNT162b2 or administered alone

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Ages Eligible for Study: | 18 Years to 64 Years (Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | Yes |
Inclusion Criteria:
- Participants 18 through 64 years of age, inclusive, at the time of consent.
- Are willing and able to comply with all scheduled visits, treatment plan, laboratory tests, lifestyle considerations, and other study procedures.
- Adults determined by clinical assessment, including medical history and clinical judgment, to be eligible for the study, including adults with preexisting stable disease, defined as disease not requiring significant change in therapy in the previous 6 weeks or hospitalization for worsening disease within 12 weeks before receipt of study intervention.
- Have received 3 prior doses of 30 µg BNT162b2, with the third dose being at least 90 days before Visit 1 (Day 1). Documented confirmation of prior BNT162b2 receipt must be obtained prior to randomization.
- Capable of giving personal signed informed consent, which includes compliance with the requirements and restrictions listed in the ICD and in this protocol.
Exclusion Criteria:
- Other 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.
- Allergy to egg proteins (egg or egg products) or chicken proteins.
- History of Guillain-Barré syndrome.
- History of severe adverse reaction associated with a vaccine and/or severe allergic reaction (eg, anaphylaxis) to any component of the study intervention(s).
- A positive SARS-CoV-2 test result (either by NAAT or rapid antigen test) within 28 days of Visit 1 (Day 1).
- Immunocompromised individuals 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.
- Vaccination with any influenza vaccine <6 months before study intervention administration, or planned receipt of any licensed or investigational nonstudy influenza vaccine during study participation.
- Individuals who receive treatment with radiotherapy or immunosuppressive therapy, including cytotoxic agents or systemic corticosteroids (if systemic corticosteroids are administered for ≥14 days at a dose of ≥20 mg/day of prednisone or equivalent), eg, for COPD, or planned receipt throughout the study. Inhaled/nebulized, intra-articular, intrabursal, or topical (skin or eyes) corticosteroids are permitted.
- Receipt of blood/plasma products or immunoglobulin, from 60 days before study intervention administration or planned receipt throughout the study.
- Receipt of any passive antibody therapy specific to COVID-19 from 90 days before study intervention administration or planned receipt throughout the study.
- Prior receipt of any COVID-19 vaccine other than BNT162b2 or receipt of more than 3 prior doses of BNT162b2.
- Participation in other studies involving study intervention within 28 days prior to study entry and/or during study participation.
- Investigator site staff or Pfizer/BioNTech employees directly involved in the conduct of the study, site staff otherwise supervised by the investigator, and their respective family members.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT05310084
Contact: Pfizer CT.gov Call Center | 1-800-718-1021 | ClinicalTrials.gov_Inquiries@pfizer.com |

Study Director: | Pfizer CT.gov Call Center | Pfizer |
Responsible Party: | BioNTech SE |
ClinicalTrials.gov Identifier: | NCT05310084 |
Other Study ID Numbers: |
C4591030 |
First Posted: | April 4, 2022 Key Record Dates |
Last Update Posted: | June 21, 2022 |
Last Verified: | June 2022 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
COVID-19 Coronavirus Vaccine SARS-CoV-2 RNA Vaccine |
COVID-19 Respiratory Tract Infections Infections Pneumonia, Viral Pneumonia Virus Diseases |
Coronavirus Infections Coronaviridae Infections Nidovirales Infections RNA Virus Infections Lung Diseases Respiratory Tract Diseases |