Safety and Immunogenicity of RNA-based Vaccines Against SARS-CoV-2 Variants in Healthy Participants

Phase 2

Completed

Conditions: SARS-CoV-2 Infection
COVID-19
SARS-CoV-2 Acute Respiratory Disease
SARS (Disease)

Interventions: Biological: Monovalent BNT162b2 (B.1.617.2)
Biological: BNT162b2
Other: Observational
Biological: Monovalent BNT162b2 (B.1.1.529.1)
Biological: Multivalent BNT162b2 (B.1.1.7 + B.1.617.2)
Biological: Monovalent BNT162b2 (B.1.1.7)

Registration Number: NCT05004181

Lead Sponsor: BioNTech SE

Brief Summary: This trial consisted of three parts, Part A, Part B, and Part C, and evaluated the safety and immunogenicity of a third (booster) injection of the multivalent vaccine BNT162b2 (B.1.1.7 + B.1.617.2), and the safety and immunogenicity of a third booster injection of the monovalent vaccine BNT162b2 (B.1.617.2) or BNT162b2 (B.1.1.7), in participants who had received two doses of the parent vaccine BNT162b2 at 30 µg, at least 6 months after the second dose of BNT162b2. It also evaluated the safety and immunogenicity of a three-dose regimen of BNT162b2 (B.1.1.7 + B.1.617.2) in participants who had not received prior Coronavirus Disease 2019 (COVID-19) vaccination. In addition, the safety and immunogenicity of BNT162b2 (B.1.1.529.1) or BNT162b2 given as a third or fourth vaccine dose to RNA COVID-19 vaccine-experienced participants with history of SARS-CoV-2 Omicron variant infection was evaluated and contrasted with the natural immune response reached after infection with the SARS-CoV-2 Omicron variant in RNA COVID-19 vaccine-experienced participants.

Detailed Description: Trial participants in Part A were assigned to one of 6 cohorts (Cohort 1-6). Trial participants in Part B were assigned to one of 3 cohorts (Cohort 1, 4, and 6). Trial participants in Part C were randomized in a 2:2:1 ratio into 3 cohorts (Cohort 7-9).

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 1380

Inclusion Criteria

Had given informed consent by signing the informed consent form (ICF) before initiation of any trial-specific procedures.
Volunteers who at the time of consent were:
Part A: 18 to 55 years old.
Part B and Part C: 18 to 85 years old (~60% should be 18 to 55 years old and ~40% 56 to 85 years old).
For Cohorts 1 to 5: In Part A, who had received BNT162b2 vaccine (30 µg, two-dose regimen) in either a clinical trial or as part of the governmental vaccination programs at least 6 months before Visit 0. Participants who were currently enrolled in the Phase III BNT162-02 / C4591001 (NCT04368728) trial, had already been unblinded, and had previously received two doses of BNT162b2 at least 6 months earlier could be included (for Cohorts 1 and 4 in Part B, prior enrollment and dosing in the C4591001 trial was mandatory). At enrollment into Part B of this trial, their participation in the C4591001 trial was terminated. Participants should have not had experienced COVID-19 based on medical history.
For Cohort 6: Were COVID-19 vaccine-naïve and had not experienced COVID-19 based on their medical history.
Were willing and able to comply with all scheduled visits, vaccination plan, laboratory tests, lifestyle considerations, and other trial procedures.
Were overall healthy at Visit 0 in the clinical judgment of the investigator based on the medical history, clinical assessment (including physical examination, vital signs, blood and urine clinical laboratory tests, 12-lead electrocardiogram (ECG), and oral swab for Nucleic Acid Amplification-based Test (NAAT)-based Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) testing).
Note: Healthy volunteers with pre-existing stable disease, defined as disease not requiring significant change in therapy or hospitalization for worsening disease during the 12 weeks before Visit 0, could be included.
Note: Volunteers who had hepatitis C (HCV) infection, but had completed curative treatment based on the medical history could be included. Volunteers who had or have hepatitis B (HBV) or human immunodeficiency virus (HIV) based on the medical history could not be included.
Agreed not to enroll in another trial of an Investigational Medicinal Product (IMP), starting after Visit 0 and continuously until the last planned visit in this trial.
Women of childbearing potential (WOCBP) had to test negative in a urine beta-human chorionic gonadotropin (β-HCG) test at Visits 0 and 1.
WOCBP had to agree to practice a highly effective form of contraception starting at Visit 0 and continuously until 28 days after their last IMP administration in this trial.
WOCBP had to confirm that they practiced an acceptable form of contraception for the 14 days prior to Visit 0.
WOCBP had to agree not to donate eggs (ova, oocytes) for the purposes of assisted reproduction starting after Visit 0 and continuously until 28 days after their last IMP injection in this trial.
Men who are sexually active with a WOCBP and had not had a vasectomy had to agree to use a highly effective form of contraception with their female partner of childbearing potential starting after Visit 0 and continuously until 28 days after their last IMP injection in this trial.
Men had to be willing to refrain from sperm donation, starting after Visit 0 and continuously until 28 days after their last vaccination.
For Part C, Cohorts 7, 8, and 9: Had received two or three documented doses of any authorized COVID-19 RNA-based vaccine (e.g., BNT162b2 [Comirnaty] or the Moderna vaccine [Spikevax]) prior to being diagnosed with SARS-CoV-2 infection from January 2022 onwards (and limited to a period when there was a high prevalence of SARS-CoV-2 Omicron infections).
Note: The interval between the last COVID-19 RNA-based vaccine administered and randomization should have been >4 months. The latest prior diagnosed SARS-CoV-2 infection should have been at least 2 months before randomization. The latest SARS-CoV-2 infection should have been documented with a result from a NAAT (as a preferable option). In case no historic NAAT result was available proving prior SARS-CoV-2 infection, the local positive result of SARS-CoV-2 N-binding antibodies done at screening was sufficient.

Exclusion Criteria

Any existing condition which could have affected vaccine injection and/or assessment of local reactions assessment, e.g., tattoos, severe scars, etc.
Any bleeding diathesis or condition associated with prolonged bleeding that could have, in the opinion of the investigator, contraindicated intramuscular injection.
Any medical or psychiatric condition including recent (within the past year) or active suicidal ideation/behavior or laboratory abnormality that, in the investigator's judgment, made the participant inappropriate for the trial.
Any current febrile illness (body temperature ≥38.0°C/≥100.4°F) or other acute illness within 48 h prior to Day 1/IMP injection in this trial.
Any current or history of cardiovascular diseases, e.g., myocarditis, pericarditis, myocardial infarction, congestive heart failure, cardiomyopathy or clinically significant arrhythmias, unless such disease was not considered relevant for participation in this trial in the investigator's judgment.
History of COVID-19 and/or clinical (based on COVID-19 symptoms/signs alone, if a SARS CoV 2 NAAT result was not available) or microbiological (based on COVID-19 symptoms/signs and a positive SARS CoV 2 NAAT result) evidence of prior infection with SARS CoV 2 at screening (Visit 0).
Note: not applicable for Part C.
History of Guillain-Barré syndrome.
Known or suspected immunodeficiency.
History of severe adverse reaction associated with a vaccine and/or severe allergic reaction (e.g., anaphylaxis) to any component of the trial IMPs.
History or known allergy, hypersensitivity, or intolerance to the trial IMP including any excipients of the IMPs in this trial.
Had received any SARS CoV 2 vaccination other than BNT162b2 (30 µg BNT162b2 given as a course of two doses approximately 21 days apart).
Note: not applicable for Part C.
Had received a live or live attenuated vaccine within 28 days prior to Day 1/IMP injection.
Had received any other vaccines within 14 days before or after any IMP injection, e.g., influenza, tetanus, pneumococcal, hepatitis A or B. When possible standard of care vaccinations should been planned with the trial IMP administrations in mind.
Individuals who received treatment with radiotherapy or immunosuppressive therapy, including cytotoxic agents or systemic corticosteroids (if systemic corticosteroids were administered for ≥14 days at a dose of ≥20 mg/day of prednisone or equivalent), e.g., for cancer or an autoimmune disease, or planned receipt throughout this trial. Inhaled/nebulized, intra-articular, intrabursal, or topical (skin or eyes) corticosteroids were permitted.
Receipt of blood/plasma products or immunoglobulin, from 60 days before IMP administration or planned receipt throughout this trial.
Participation in other trials involving IMP within 28 days or 5 half-lives (whichever was longer) prior to Visit 1 and/or during trial participation, besides participation in trials with BNT162b2.
Were pregnant or breastfeeding or are planning pregnancy within 28 days after last IMP treatment.
Were vulnerable individuals as per International Conference on Harmonisation (ICH) E6 definition, i.e., are individuals whose willingness to volunteer in a clinical trial may be unduly influenced by the expectation, whether justified or not, of benefits associated with participation, or of a retaliatory response from senior members of a hierarchy in case of refusal to participate.
For Part C, Cohorts 7, 8, and 9: Vaccination with other non-RNA or unauthorized COVID-19 vaccines.
For Part C, Cohorts 7, 8, and 9: Vaccination with any COVID-19 vaccine after SARS-CoV-2 infection from January 2022 onwards (and limited to a period when there was a high prevalence of SARS-CoV-2 Omicron infections).

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Part B - Cohort 4: 18 to 85 years of age	Monovalent BNT162b2 (B.1.617.2)	Participants received 1 dose of BNT162b2 (B.1.617.2) of 30 µg.
Part C - Cohort 8: 18 to 85 years of age	BNT162b2	Participants received 1 dose of BNT162b2 of 30 µg.
Part C - Cohort 9: 18 to 85 years of age	Observational	Participants received no vaccination within 3 months after Visit 1.
Part C - Cohort 7: 18 to 85 years of age	Monovalent BNT162b2 (B.1.1.529.1)	Participants received 1 dose of BNT162b2 (B.1.1.529.1) of 30 µg.
Part B - Cohort 6: 18 to 85 years of age	Multivalent BNT162b2 (B.1.1.7 + B.1.617.2)	Participants received 3 doses of BNT162b2 (B.1.1.7 + B.1.617.2) of 30 µg.
Part A - Cohort 1: 18 to 55 years of age	Multivalent BNT162b2 (B.1.1.7 + B.1.617.2)	Participants received 1 dose of BNT162b2 (B.1.1.7 + B.1.617.2) of 30 µg.
Part A - Cohort 2: 18 to 55 years of age	Multivalent BNT162b2 (B.1.1.7 + B.1.617.2)	Participants received 2 doses of BNT162b2 (B.1.1.7 + B.1.617.2) of 30 µg.
Part A - Cohort 3: 18 to 55 years of age	Monovalent BNT162b2 (B.1.1.7)	Participants received1 dose of BNT162b2 (B.1.1.7) of 30 µg.
Part A - Cohort 4: 18 to 55 years of age	Monovalent BNT162b2 (B.1.617.2)	Participants received 1 dose of BNT162b2 (B.1.617.2) of 30 µg.
Part A - Cohort 5: 18 to 55 years of age	BNT162b2	Participants received 1 dose of BNT162b2 of 30 µg.
Part A - Cohort 6: 18 to 55 years of age	Multivalent BNT162b2 (B.1.1.7 + B.1.617.2)	Participants received 3 doses of BNT162b2 (B.1.1.7 + B.1.617.2) of 30 µg.
Part B - Cohort 1: 18 to 85 years of age	Multivalent BNT162b2 (B.1.1.7 + B.1.617.2)	Participants received 1 dose of BNT162b2 (B.1.1.7 + B.1.617.2) of 30 µg.

Primary Outcome Measures

Name	Time	Method
All Parts - Percentage of Participants Reporting Local Reactions at the Injection Site (Pain, Tenderness, Erythema/Redness, Induration/Swelling)	from Day 1 to Day 7 after each IMP dose	Local reactions of any grade are reported. Local reactions were graded using criteria based on the US FDA Guidance for Industry "Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials"; the guidance uses the Grades 1 (mild), 2 (moderate), 3 (severe), and 4 (potentially life-threatening). The reporting of systemic reactions was based on the participant's assessments collected in the electronic diary (e-diary) or mapped from the adverse event case report form from Day 1 to Day 7 after each IMP dose. For Erythema/redness and Induration/swelling, the reported size had to be at least 2.5 cm to be deemed as a local reaction. Local reactions with a size less than 2.5 cm are not included in the analysis. Subjects in Cohort 9 did not receive a vaccination and are not included in this analysis.
All Parts - Percentage of Participants Reporting Systemic Events (Fever, Fatigue, Headache, Chills, Vomiting, Nausea, Diarrhea, New or Worsened Muscle Pain, and New or Worsened Joint Pain)	from Day 1 to Day 7 after each IMP dose	Systemic reactions of any grade are reported. Systemic reactions were graded using criteria based on the guidance given in the US FDA Guidance for Industry "Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials"; the guidance uses the Grades 1 (mild), 2 (moderate), 3 (severe), and 4 (potentially life-threatening). The reporting of systemic reactions was based on the participant's assessments collected in the e-diary or mapped from the adverse event case report form from Day 1 to Day 7 after each IMP dose. For Fever, the reported oral temperature had to be ≥38.0°C to be deemed as a systemic event. Oral temperature less than 38.0°C are not included in the analysis. Subjects in Cohort 9 did not receive a vaccination and are not included in this analysis.
All Parts - Percentage of Participants Reporting Adverse Events (AEs)	Dose 1 up to 1 month after each dose (all parts)	An AE is defined as TEAE if the event onset date and time is after the first IMP dose (if the event was absent before the first administration of the IMP) or worsened after the first IMP dose (if the event was present before the first administration of the IMP). In the event of an incomplete onset date, the event is considered as treatment-emergent unless the partial onset date information or complete or partial end date confirms the onset date or the event end prior to the first dose of IMP. Percentages for dose 1, dose 2, dose 3 and overall summaries are based upon the number of participants who received the respective IMP dose.
All Parts - Percentage of Participants Reporting Serious Adverse Events (SAEs)	Dose 1 up to 6 months after the last dose	An SAE was any untoward medical occurrence that, at any dose: resulted in death; was life-threatening; required inpatient hospitalization or prolongation of existing hospitalization; resulted in persistent disability/ incapacity; was a congenital anomaly/birth defect and/or was another important medical event. SAEs from dose 1 up to 6 months post last IMP dose are presented. MedDRA (version 26.1) coding dictionary applied. An SAE is defined as TESAE if the event onset date and time is after the first IMP dose (if the event was absent before the first administration of the IMP) or worsened after the first IMP dose (if the event was present before the first administration of the IMP). In the event of an incomplete onset date, the event is considered as treatment-emergent unless the partial onset date information or complete or partial end date confirms the onset date or the event end prior to the first dose of IMP.
Part B - GMR of B.1.1.7 NT 1 Month After 1 Dose of BNT162b2 (B.1.1.7 + B.1.617.2) in BNT162b2-experienced Participants to the Reference Strain NT 1 Month After 2 Doses of BNT162b2 in Participants From the Phase III C4591001 (NCT04368728) Trial	1 month after booster dose in BNT162-17 participants and 1 month post Dose 2 in participants from the C4591001 (NCT04368728) trial	GMRs and 2-sided 95% CIs were calculated by exponentiating the difference of least square means and corresponding CIs based on the analysis of logarithmically transformed neutralizing titers using a linear regression model with terms of age, sex, and vaccine group. The overall number of participants analyzed represents the number of participants with valid and determinate assay results for B.1.1.7 and reference strain respectively at the given dose/sampling time point within the specified window. GMR data are presented below as per the primary endpoint defined in the protocol. GMTs for the individual arms (from which GMR was derived) were secondary endpoints and are presented in outcome measure 22. GMR = Geometric mean ratio; NT = neutralizing titers
Part B - GMR of B.1.617.2 NT 1 Month After 1 Dose of BNT162b2 (B.1.1.7 + B.1.617.2) in BNT162b2-experienced Participants to the Reference Strain NT 1 Month After 2 Doses of BNT162b2 in Participants From the Phase III C4591001 (NCT04368728) Trial	1 month after booster dose in BNT162-17 participants and 1 month post Dose 2 in participants from the C4591001 (NCT04368728) trial	GMRs and 2-sided 95% CIs were calculated by exponentiating the difference of least square means and corresponding CIs based on the analysis of logarithmically transformed neutralizing titers using a linear regression model with terms of age, sex, and group. The overall number of participants analyzed represents the number of participants with valid and determinate assay results for B.1.617.2 and reference strain respectively at the given dose/sampling time point within the specified window. GMR data are presented below as per the primary endpoint defined in the protocol. GMTs for the individual arms (from which GMR was derived) were secondary endpoints and are presented in outcome measure 22. GMR = Geometric mean ratio; NT = neutralizing titers
Part B - GMR of B.1.617.2 NT 1 Month After 1 Dose of BNT162b2 (B.1.617.2) in BNT162b2-experienced Participants to the Reference Strain NT 1 Month After 2 Doses of BNT162b2 in Participants From the Phase III C4591001 (NCT04368728) Trial	1 month after booster dose in BNT162-17 participants and 1 month post Dose 2 in participants from the C4591001 (NCT04368728) trial	GMRs and 2-sided 95% CIs were calculated by exponentiating the difference of least square means and corresponding CIs based on the analysis of logarithmically transformed neutralizing titers using a linear regression model with terms of age, sex, and group. The overall number of participants analyzed represents the number of participants with valid and determinate assay results for B.1.617.2 and reference strain respectively at the given dose/sampling time point within the specified window. GMR data are presented below as per the primary endpoint defined in the protocol. GMTs for the individual arms (from which GMR was derived) were secondary endpoints and are presented in outcome measure 24.
Part B - Difference in Seroresponse (SR) to B.1.1.7 NT 1 Month After 1 Dose of BNT162b2 (B.1.1.7 + B.1.617.2) in BNT162b2-experienced Participants to the Reference Strain NT 1 Month After 2 Doses of BNT162b2 in Participants From C4591001 (NCT04368728)	1 month after booster dose in BNT162-17 participants and 1 month post Dose 2 in participants from the C4591001 (NCT04368728) trial	Seroresponse was defined as a ≥4-fold rise in neutralizing titer from baseline. For subjects with a baseline titer less than the lower limit of quantitation (\<LLOQ), seroresponse was defined as a post-vaccination titer of ≥4× LLOQ. Adjusted difference was estimated using minimum risk weights and stratified by sex and age group (18 to 55 years, 56 to 85 years), expressed as a percentage. Associated 2-sided 95% CI based on the Newcombe method with minimum risk weights for the difference in proportions. Difference in seroresponse data are presented below as per the primary endpoint defined in the protocol. Seroresponses for the individual arms (from which the difference was derived) were secondary endpoints and are presented in outcome measure 23.
Part B - Difference in SR to B.1.617.2 NT 1 Month After 1 Dose of BNT162b2 (B.1.1.7 + B.1.617.2) in BNT162b2-experienced Participants to the Reference Strain NT 1 Month After 2 Doses of BNT162b2 in Participants From C4591001 (NCT04368728)	1 month after booster dose in BNT162-17 participants and 1 month post Dose 2 in participants from the C4591001 (NCT04368728) trial	Seroresponse was defined as a ≥4-fold rise in neutralizing titer from baseline. For subjects with a baseline titer less than the lower limit of quantitation (\<LLOQ), seroresponse was defined as a post-vaccination titer of ≥4× LLOQ. Adjusted difference was estimated using minimum risk weights and stratified by sex and age group (18 to 55 years, 56 to 85 years), expressed as a percentage. Associated 2-sided 95% CI based on the Newcombe method with minimum risk weights for the difference in proportions. Difference in seroresponse data are presented below as per the primary endpoint defined in the protocol. Seroresponses for the individual arms (from which the difference was derived) were secondary endpoints and are presented in outcome measure 23.
Part B - Difference in SR to B.1.617.2 NT 1 Month After 1 Dose of BNT162b2 (B.1.617.2) in BNT162b2-experienced Participants to the Reference Strain NT 1 Month After 2 Doses of BNT162b2 in Participants From C4591001 (NCT04368728)	1 month after booster dose in BNT162-17 participants and 1 month post Dose 2 in participants from the C4591001 (NCT04368728) trial	Seroresponse was defined as a ≥4-fold rise in neutralizing titer from baseline. For subjects with a baseline titer less than the lower limit of quantitation (\<LLOQ), seroresponse was defined as a post-vaccination titer of ≥4× LLOQ. Adjusted difference was estimated using minimum risk weights and stratified by sex and age group (18 to 55 years, 56 to 85 years), expressed as a percentage. Associated 2-sided 95% CI based on the Newcombe method with minimum risk weights for the difference in proportions. Difference in seroresponse data are presented below as per the primary endpoint defined in the protocol. Seroresponses for the individual arms (from which the difference was derived) were secondary endpoints and are presented in outcome measure 25.
Part B - GMR of B.1.1.7 NT 1 Month After 2 Doses of BNT162b2 (B.1.1.7 + B.1.617.2) in COVID-19 Vaccine-naïve Participants to the Reference Strain NT 1 Month After 2 Doses of BNT162b2 in Participants From the C4591001 (NCT04368728) Trial	1 month	Cohort B6 aimed to generate data to support a 2-dose primary regimen of alpha-delta multivalent BNT162b2 vaccine in SARS-CoV-2 naïve, unvaccinated individuals. The population recruited in Cohort B6, while complying with the inclusion criterium of no known history SARS-CoV-2 infection, were retrospectively seropositive for SARS-CoV-2 by planned N-binding antibody assessment of baseline samples. While the cohort was COVID-19 vaccine-naïve, it was not SARS-CoV-2-naïve as needed to match the control group (C4591001/NCT04368728). Procedurally, submission of a protocol amendment was not possible. However, the Statistical Analysis Plan was amended to describe that the non-inferiority analysis could not be performed according to the protocol. Control participants were not selected as planned; therefore, data were not available to calculate the GMR. Available GMT data for the 17 Cohort B6 participants without evidence of infection were analyzed and are presented in Outcome Measure 28.
Part B - GMR of B.1.617.2 NT 1 Month After 2 Doses of BNT162b2 (B.1.1.7 + B.1.617.2) in COVID-19 Vaccine-naïve Participants to the Reference Strain NT 1 Month After 2 Doses of BNT162b2 in Participants From the C4591001 (NCT04368728) Trial	1 month	Cohort B6 aimed to generate data to support a 2-dose primary regimen of alpha-delta multivalent BNT162b2 vaccine in SARS-CoV-2 naïve, unvaccinated individuals. The population recruited in Cohort B6, while complying with the inclusion criterium of no known history SARS-CoV-2 infection, were retrospectively seropositive for SARS-CoV-2 by planned N-binding antibody assessment of baseline samples. While the cohort was COVID-19 vaccine-naïve, it was not SARS-CoV-2-naïve as needed to match the control group (C4591001/NCT04368728). Procedurally, submission of a protocol amendment was not possible. However, the Statistical Analysis Plan was amended to describe that the non-inferiority analysis could not be performed according to the protocol. Control participants were not selected as planned; therefore, data were not available to calculate the GMR. Available GMT data for the 17 Part B Cohort 6 participants without evidence of infection were analyzed and are presented in Outcome Measure 28.
Part B - The Difference in SR to B.1.1.7 NT 1 Month After 2 Doses of BNT162b2 (B.1.1.7 + B.1.617.2) in COVID-19 Vaccine-naïve Participants to the Reference Strain NT 1 Month After 2 Doses of BNT162b2 in Participants From the C4591001 (NCT04368728) Trial	1 month	Cohort B6 aimed to generate data to support a 2-dose primary regimen of alpha-delta multivalent BNT162b2 vaccine in SARS-CoV-2 naïve, unvaccinated individuals. The population recruited in Cohort B6, while complying with the inclusion criterium of no known history SARS-CoV-2 infection, were retrospectively seropositive for SARS-CoV-2 by planned N-binding antibody assessment of baseline samples. While the cohort was COVID-19 vaccine-naïve, it was not SARS-CoV-2-naïve as needed to match the control group (C4591001/NCT04368728). Procedurally, submission of a protocol amendment was not possible. However, the Statistical Analysis Plan was amended to describe that non-inferiority analysis could not be performed according to the protocol. Control participants were not selected as planned; therefore, data were not available to calculate difference in SR. Available SR data for the 17 Part B Cohort 6 participants without evidence of infection were analyzed and presented in Outcome Measure 31.
Part B - The Difference in SR to B.1.617.2 NT 1 Month After 2 Doses of BNT162b2 (B.1.1.7 + B.1.617.2) in COVID-19 Vaccine-naïve Participants to the Reference Strain NT 1 Month After 2 Doses of BNT162b2 in Participants From the C4591001 (NCT04368728) Trial	1 month	Cohort B6 aimed to generate data to support a 2-dose primary regimen of alpha-delta multivalent BNT162b2 vaccine in SARS-CoV-2 naïve, unvaccinated individuals. The population recruited in Cohort B6, while complying with the inclusion criterium of no known history SARS-CoV-2 infection, were retrospectively seropositive for SARS-CoV-2 by planned N-binding antibody assessment of baseline samples. While the cohort was COVID-19 vaccine-naïve, it was not SARS-CoV-2-naïve as needed to match the control group (C4591001/NCT04368728). Procedurally, submission of a protocol amendment was not possible. However, the Statistical Analysis Plan was amended to describe that the non-inferiority analysis could not be performed according to the protocol. Control participants were not selected as planned; therefore data were not available to calculate difference in SR. Available SR data for the 17 Part B Cohort 6 participants without evidence of infection were analyzed and presented in Outcome Measure 31.
Part B - GMR of Reference Strain NT After One Dose of BNT162b2 (B.1.1.7 + B.1.617.2) in Participants With Evidence of Prior Infection to the Reference Strain NT After 2 Doses of BNT162b2 in Participants Without Evidence of Infection	3 weeks post Dose 1 in BNT162-17 participants and 1 month post Dose 2 in participants from the C4591001 (NCT04368728) trial	GMR of reference strain NT 3 weeks (3W) after one dose (PD1) of BNT162b2 (B.1.1.7 + B.1.617.2) in COVID-19 vaccine-naïve participants with evidence of prior infection to the reference strain NT 1 month after two doses of BNT162b2 in participants without evidence of infection (COVID-19 Vaccine-naïve Participants) from the Phase III trial C4591001 (NCT04368728). GMTs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of the titers and corresponding CIs (based on the Student t distribution). Assay results below LLOQ were set to 0.5 × LLOQ. GMTs of NTs are presented in the descriptive data section of this outcome measure. GMRs and 2-sided 95% CIs were calculated by exponentiating the difference of LS means and corresponding CIs based on the analysis of logarithmically transformed neutralizing titers using a linear regression model with terms of age, sex, and group. GMR data are presented in the statistical analysis section.
Part B - The Difference in SRs to the Reference Strain NT in Subjects With Evidence of Prior Infection and to the Reference Strain NT in Participants Without Evidence of Infection (COVID-19 Vaccine-naïve Participants)	3 weeks post Dose 1 in BNT162-17 participants and 1 month post Dose 2 in participants from the C4591001 (NCT04368728) trial	The difference in SRs to the reference strain NT 3 weeks after one dose of BNT162b2 (B.1.1.7 + B.1.617.2) in COVID-19 vaccine-naïve participants with evidence of prior infection to the reference strain NT 1 month after two doses of BNT162b2 in participants without evidence of infection from the Phase III trial C4591001 (NCT04368728). SR was defined as achieving a ≥4-fold rise from baseline. If the baseline measurement was below the LLOQ, a post-vaccination assay result ≥4 × LLOQ was considered a SR. SR to the reference strain NTs are presented in the descriptive data section of this outcome measure. Adjusted difference in proportions was estimated using minimum risk weights and stratified by sex and age group (18 to 55 years, 56 to 85 years), expressed as a percentage. 2-Sided CI was based on the Newcombe method with minimum risk weights for the difference in proportions. Difference in SR data are presented in the statistical analysis section.
Part C - GMR of B.1.1.529.1 NT 1 Month After One Dose of BNT162b2 (B.1.1.529.1) in RNA-based COVID-19 Vaccine-experienced Participants With History of SARS-CoV-2 Infection to Those at 1 Month After One Dose of BNT162b2 for Cohorts 7 and 8.	1 month after 1 dose of BNT162b2 or BNT162b2 (B.1.1.529.1)	GMRs and 2-sided 95% CIs were calculated by exponentiating the difference of least square means and corresponding CIs based on the analysis of logarithmically transformed neutralizing titers using a linear regression model with terms of age and number of prior doses. The overall number of participants analyzed represents the number of participants with valid and determinate assay results for B.1.1.529.1 at the given dose/sampling time point within the specified window. GMR data are presented below as per the primary endpoint defined in the protocol. GMTs for the individual arms (from which the difference was derived) were secondary endpoints and are presented in outcome measure 32.
Part C - The Difference in SR of B.1.1.529.1 NT 1 Month After One Dose of BNT162b2 (B.1.1.529.1) in RNA-based COVID-19 Vaccine-experienced Participants With History of SARS-CoV-2 Infection to Those at 1 Month After One Dose of BNT162b2 for Cohorts 7 & 8.	1 month after 1 dose of BNT162b2 or BNT162b2 (B.1.1.529.1)	SR was defined as a ≥4-fold rise in neutralizing titer from baseline. For participants with a baseline titer less than the lower limit of quantitation (\<LLOQ), SR was defined as a post-vaccination titer of ≥4× LLOQ. SR to the reference strain NTs are presented in the descriptive data section of this outcome measure. Adjusted difference was estimated using minimum risk weights and stratified by sex and age group (18 to 55 years, 56 to 85 years), expressed as a percentage. Associated 2-sided 95% CI were based on the Newcombe method with minimum risk weights for the difference in proportions. Difference in SR data are presented in the statistical analysis section.

Secondary Outcome Measures

Name	Time	Method
Part A - Geometric Mean Titer (GMT) at Each Timepoint	Day 1 up to Day 421	For BNT162b2-experienced participants (defined as participants who have previously received two injections of 30 μg BNT162b2). Reference and variant(s) of concern (VOC) specific NT. GMTs and 2-sided 95% CIs are calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ are set to 0.5 × LLOQ and above the ULOQ are set to ULOQ. Cohorts 1, 3, 4 and 5 received only 1 dose of IMP. Cohort 2 received dose 2 on Day 56 and did not receive dose 3. Cohort 6 received dose 2 on Day 21 and received dose 3 approximately 6 months after dose 2.
Part A - Geometric Mean Fold Rises (GMFR) From Before Vaccination to Each Subsequent Time Point After Vaccination	Day 1 to Day 421	For BNT162b2-experienced participants (defined as participants who have previously received two injections of 30 μg BNT162b2). Reference and VOC specific NT. GMFR is calculated as the mean of the difference of logarithmically transformed neutralization titers or antibody levels (later result minus earlier result) and exponentiating the mean. The associated 2-sided 95% CIs are obtained by constructing CIs using Student's t-distribution for the mean difference on the natural log scale and exponentiating the confidence limits. Assay results below the LLOQ are set to 0.5 × LLOQ and above the ULOQ are set to ULOQ. Cohorts 1, 3, 4 and 5 received only 1 dose of IMP. Cohort 2 received dose 2 on Day 56 and did not receive dose 3. Cohort 6 received dose 2 on Day 21 and received dose 3 approximately 6 months after dose 2.
Part A - Percentage of Participants Achieving SR in Terms of NT at Each Post Vaccination Time Point	Day 1 to Day 421	For BNT162b2-experienced participants (defined as participants who have previously received two injections of 30 μg BNT162b2). Reference and VOC specific NT. SR is defined as a ≥4-fold rise in neutralizing titer from baseline (pre IMP dose 1). For subjects with a baseline titer less than the LLOQ, SR is defined as a post-vaccination titer of ≥4 × LLOQ. Pre IMP dose 2 is also 2 months post dose 1 for Cohort 2 and 3 weeks post dose 1 for Cohort 6. Cohorts 1, 3, 4 and 5 received only 1 dose of IMP. Cohort 2 received dose 2 on Day 56 and did not receive dose 3. Cohort 6 received dose 2 on Day 21 and received dose 3 approximately 6 months after dose 2.
Part B - GMT of VOCs and Reference Strains in Part B Cohort 1 and Control	1 month after booster dose in BNT162-17 participants and 1 month post Dose 2 in participants from the C4591001 (NCT04368728) trial	GMTs of VOCs (B.1.1.7 and B.1.617.2) and reference strain 1 month after 1 dose of BNT162 (B.1.1.7+B.1.167.2) in participants from Part B Cohort 1 of the BNT162-17 trial (BNT162b2-experienced participants), and reference strain 1 month after 2 doses of BNT162b2 in selected participants from the Phase III C4591001 (NCT04368728) trial. GMTs and 2-sided 95% CIs are calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ are set to 0.5 × LLOQ and above the ULOQ are set to ULOQ.
Part B - SR of of VOCs and Reference Strains in Part B Cohort 1 and Control	1 month after Dose 1 in BNT162-17 participants and 1 month post Dose 2 in participants from the C4591001 (NCT04368728) trial	Percentage of participants achieving SR at 1 month after 1 dose of BNT162b2 (B.1.1.7 + B.1.617.2) in BNT162b2-experienced participants (Cohort 1) and 1 month after 2 doses of BNT162b2 primary series (participants from C4591001 \[NCT04368728\]). SR is defined as a ≥4-fold rise in neutralizing titer from baseline (pre IMP dose 1). For participants with a baseline titer less than the LLOQ, SR is defined as a post-vaccination titer of ≥4 × LLOQ.
Part B - GMT of VOCs and Reference Strains in Part B Cohort 4 and Control	1 month after booster dose in BNT162-17 participants and 1 month post Dose 2 in participants from the C4591001 (NCT04368728) trial	GMTs of VOCs (B.1.617.2) and reference strain 1 month after 1 dose of BNT162 (B.1.167.2) in participants from Part B Cohort 4 of the BNT162-17 trial (BNT162b2-experienced participants), and 1 month after 2 doses of BNT162b2 in selected participants from the Phase III C4591001 (NCT04368728) trial. GMTs and 2-sided 95% CIs are calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ are set to 0.5 × LLOQ and above the ULOQ are set to ULOQ.
Part B - SR of of VOCs and Reference Strains in Part B Cohort 4 and Control	1 month after Dose 1 in BNT162-17 participants and 1 month post Dose 2 in participants from the C4591001 (NCT04368728) trial	Percentage of participants achieving SR at 1 month after 1 dose of BNT162b2 (B.1.617.2) in BNT162b2-experienced subjects (Part B - Cohort 4) and 1 month after 2 doses of BNT162b2 primary series (participants from C4591001 \[NCT04368728\]). SR is defined as a ≥4-fold rise in neutralizing titer from baseline (pre IMP dose 1). For participants with a baseline titer less than the LLOQ, SR is defined as a post-vaccination titer of ≥4 × LLOQ.
Part B - GMT of VOCs and Reference Strain in Part B Cohort 6 1 Month After Dose 2 and 1 Month After Dose 3	1 month after Dose 2 and 1 month after Dose 3	GMTs of VOCs and reference strain NT 1 month after dose 2 and dose 3 of BNT162b2 (B.1.1.7 + B.1.617.2) (Part B - Cohort 6). GMTs and 2-sided 95% CIs are calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ are set to 0.5 × LLOQ and above the ULOQ are set to ULOQ.
Part B - Cohort 6 - Percentages With SRs to VOCs (B.1.1.7, B.1.617.2) and Reference Strain	1 month after Dose 2 and 1 month after Dose 3	Percentage of participants achieving SR to VOCs (B.1.1.7, B.1.617.2) and reference strain at 1 month after dose 2 and dose 3 of BNT162b2 (B.1.1.7 + B.1.617.2) (Part B - Cohort 6). SR is defined as a ≥4-fold rise in neutralizing titer from baseline (pre IMP dose 1). For participants with a baseline titer less than the LLOQ, SR is defined as a post vaccination titer of ≥4 × LLOQ. Pre IMP dose 2 is also 3 weeks post dose 1 for Cohort 6.
Part B - GMTs of VOC in COVID-19 Vaccine-naïve Participants With and Without Evidence of Prior Infection in Part B C6 (1 and 2 Primary Doses Respectively) and in BNT162b2-Experienced Participants Without Evidence of Infection in Part B C1 (1 Booster Dose)	Day 1 up to 1 month after 1 booster dose in Part B Cohort 1 without evidence of infection, up to 1 month after 2 doses in Part B Cohort 6 without evidence of infection and up to 3 weeks after 1 dose in Part B Cohort 6 with evidence of prior infection	GMTs of VOC specific NTs (B.1.1.7, B.1.617.2, B.1.1.529.5 \[Omicron BA.5\]) 3 weeks after one dose of BNT162b2 (B.1.1.7 + B.1.617.2) in COVID-19 vaccine-naïve participants with evidence of prior infection (Cohort 6), 1 month after two doses of BNT162b2 (B.1.1.7 + B.1.617.2) in COVID-19 vaccine-naïve participants without evidence of infection (Cohort 6), and 1 month after one booster dose of BNT162b2 (B.1.1.7 + B.1.617.2) in BNT162b2-experienced participants without evidence of infection (Cohort 1). GMTs 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; assay results above the ULOQ were set to ULOQ.
Part B - GMRs of VOC in COVID-19 Vaccine-naïve Participants With and Without Evidence of Prior Infection (1 and 2 Primary Doses Respectively) and in BNT162b2-Experienced Participants Without Evidence of Infection (1 Booster Dose)	Day 1 to Day 29	GMR of VOC specific NTs (B.1.1.7, B.1.617.2, B.1.1.529.5 \[Omicron BA.5\]) 3 weeks after one dose of BNT162b2 (B.1.1.7 + B.1.617.2) in COVID-19 vaccine-naïve participants with evidence of prior infection (Cohort 6) to the VOCs NTs 1 month after two doses of BNT162b2 (B.1.1.7 + B.1.617.2) in participants without evidence of infection (Cohort 6), and to the VOCs NTs 1 month after one booster dose of BNT162b2 (B.1.1.7 + B.1.617.2) in BNT162b2-experienced participants without evidence of infection (Cohort 1). GMRs and 2-sided 95% CIs were calculated by exponentiating the difference of the LS means and corresponding CIs based on the analysis of logarithmically transformed neutralizing titers using a linear regression model with terms of age, sex, and group. A separate model was fit for each comparison. Assay results below the LLOQ were set to 0.5 × LLOQ; assay results above the ULOQ were set to ULOQ.
Part B - Difference in SRs to VOCs in COVID-19 Vaccine-naïve Participants With and Without Evidence of Prior Infection (1 and 2 Primary Doses Respectively) and in BNT162b2-Experienced Participants Without Evidence of Infection (1 Booster Dose)	Day 1 to Day 29	The difference in SRs to VOC specific NTs (B.1.1.7, B.1.617.2, B.1.1.529.5 \[Omicron BA.5\]) 3 weeks after one dose of BNT162b2 (B.1.1.7 + B.1.617.2) in COVID-19 vaccine-naïve participants with evidence of prior infection (Cohort 6) to those 1 month after two doses of BNT162b2 (B.1.1.7 + B.1.617.2) in participants without evidence of infection (Cohort 6), and to those 1 month after one booster dose of BNT162b2 (B.1.1.7 + B.1.617.2) in BNT162b2-experienced participants without evidence of infection (Cohort 1). Adjusted difference in proportions estimated using minimum risk weights and stratified by sex and age group (18 to 55 years, 56 to 85 years), expressed as a percentage. 2-Sided CI based on the Newcombe method stratified by sex and age group (18 to 55 years, 56 to 85 years) with minimum risk weights for the difference in proportions.
Part B - SR of VOC in COVID-19 Vaccine-naïve Participants With and Without Evidence of Prior Infection (1 and 2 Primary Doses Respectively) and in BNT162b2-Experienced Participants Without Evidence of Infection (1 Booster Dose)	3 weeks after one dose in participants with evidence of prior infection (Cohort 6), 1 month after two doses in participants without evidence of infection (Cohort 6), and 1 month after one booster dose (Cohort 1)	SRs of VOC specific NTs (B.1.1.7, B.1.617.2, B.1.1.529.5 \[Omicron BA.5\]) 3 weeks after one dose of BNT162b2 (B.1.1.7 + B.1.617.2) in COVID-19 vaccine-naïve participants with evidence of prior infection (Cohort 6) 1 month after two doses of BNT162b2 (B.1.1.7 + B.1.617.2) in participants without evidence of infection (Cohort 6), and 1 month after one booster dose of BNT162b2 (B.1.1.7 + B.1.617.2) in BNT162b2-experienced participants without evidence of infection (Cohort 1). Seroresponse was defined as achieving a ≥4-fold rise from baseline. If the baseline measurement was below the LLOQ, a postvaccination assay result ≥4 × LLOQ was considered a seroresponse.
Part C - GMT - B.1.1.529.1 in RNA Based COVID-19 Vaccine-experienced Participants With History of SARS-CoV-2 Infection	Day 1 to Day 360	VOC NT in RNA-based COVID-19 vaccine-experienced participants with history of SARS-CoV-2 infection at baseline and 7 days, 1 month, and 3 months after the trial start for Cohorts 7, 8, and 9, and 6 and 12 months after the trial start for Cohorts 7 and 8. GMTs and 2-sided 95% CIs are calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ are set to 0.5 × LLOQ and above the ULOQ are set to ULOQ. Number of subjects with valid and determinate assay results for the specified variant at the given dose/sampling time point. No vaccination was given to Cohort 9 participants within 3 months after Visit 1. The term "post IMP" does not apply for Cohort 9 since no IMP was given, but blood was collected at the same timepoints post randomization.

Trial Locations

Locations (35): Stamford Therapeutics Consortium
🇺🇸
Stamford, Connecticut, United States
North Texas Infectious Diseases Consultants
🇺🇸
Dallas, Texas, United States
Atlanta Center for Medical Research
🇺🇸
Atlanta, Georgia, United States
Collaborative Neuroscience Network LLC
🇺🇸
Long Beach, California, United States
Clinical Research Consulting, Llc
🇺🇸
Milford, Connecticut, United States
Meridian Clinical Research
🇺🇸
Savannah, Georgia, United States
Rochester Clinical Research
🇺🇸
Rochester, New York, United States
Amici Clinical Research
🇺🇸
Warren, New Jersey, United States
Medpharmics, LLC
🇺🇸
Gulfport, Mississippi, United States
ARC Clinical Research
🇺🇸
Austin, Texas, United States
CRS Clinical Research Services Berlin
🇩🇪
Berlin, Germany
CRS Clinical Research Services Mannheim GmbH
🇩🇪
Mannheim, Germany
IKF Institut fuer klinische Forschung Frankfurt
🇩🇪
Frankfurt am Main, Germany
Langeberg Medicross Medical Centre
🇿🇦
Kraaifontein, Western Cape, South Africa
Studienzentrum Brinkum Dr. Lars Pohlmeier und Torsten Drescher
🇩🇪
Stuhr, Germany
JOSHA Research
🇿🇦
Bloemfontein, Free State, South Africa
Synexus Helderberg Clinical Trial Centre
🇿🇦
Somerset West, Western Cape, South Africa
Paarl Research Centre
🇿🇦
Paarl, Western Cape, South Africa
Worthwhile Clinical Trials
🇿🇦
Benoni, South Africa
Tiervlei Trial Centre
🇿🇦
Cape Town, South Africa
Midrand Medical Centre
🇿🇦
Halfway House, South Africa
Newtown Clinical Research
🇿🇦
Johannesburg, South Africa
Botho ke Bontle Health Service
🇿🇦
Pretoria, South Africa
Jongaie Research, Medicross Pretoria West
🇿🇦
Pretoria, South Africa
Hacettepe University Hospital
🇹🇷
Ankara, Turkey
Ankara University Faculty of Medicine, Avicenna Hospital
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Ankara, Turkey
Bagcilar Medipol Mega University Hospital
🇹🇷
Istanbul, Turkey
Istanbul University Medical Faculty
🇹🇷
Istanbul, Turkey
Kocaeli Universitesi Tip Fakultesi
🇹🇷
Kocaeli, Turkey
Aventiv Research Inc.
🇺🇸
Columbus, Ohio, United States
California Research Foundation
🇺🇸
San Diego, California, United States
Clinical Trials of Texas Inc.
🇺🇸
San Antonio, Texas, United States
Diagnostics Research Group
🇺🇸
San Antonio, Texas, United States
Global Clinical Trials
🇿🇦
Pretoria, South Africa
Synexus SA Stanza Clinical Research Centre
🇿🇦
Pretoria, South Africa