Trial Outcomes & Findings for This Study Intends to Describe the Characteristics of Patients Given the Pfizer-BioNTech Bivalent mRNA COVID-19 Vaccine and Any Commercially Available Influenza Vaccines at the Same Time Versus at Different Times. (NCT NCT05858450)

NCT ID: NCT05858450

Last Updated: 2024-09-20

Results Overview

Hospitalization due to any cause is defined as an overnight stay, or longer, in a hospital environment (emergency room, observation unit or in-patient care, or similar facility including admission to a day care facility). To account for imbalance in participant characteristics between the vaccine exposure groups, 2 separate logistic regression models were used. The two models were: Model 1: Same day vs COVID-19 alone, and Model 2: Same day vs Flu (SIV) alone.

Recruitment status

COMPLETED

Target enrollment

3442996 participants

Primary outcome timeframe

From Day 15 of vaccination till end of follow-up observation period, from 14-Sep-2022 through 14 February 2023 (approximately 5 months); data was extracted and observed in this retrospective study from 05-May-2023 to 12-May-2023 (8 days)

Results posted on

2024-09-20

Participant Flow

Adult participants (greater than or equal to \[\>=\] 18 years) who were enrolled in the Optum Clinformatics Database as of 31 August 2022 and had received a Pfizer-BioNTech messenger ribonucleic acid (mRNA) bivalent COVID-19 vaccine and/or seasonal influenza/flu vaccine (SIV) anytime between 31 August 2022 and 30 January 2023 were included in this retrospective, observational study.

Outcome measures were compared using Cox Proportional Hazards models for the following exposure groups: comparison 1: co-administration of vaccines on the same day and COVID-19 vaccine alone, comparison 2: co-administration of vaccines on the same day (excluded participants with unknown/other region) and SIV alone.

Participant milestones

Participant milestones
Measure
Group 1a: Same Day COVID-19 Vaccine and SIV, 18-64 Years
Participants included in this group were aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023.
Group 2a: COVID-19 Vaccine Alone, 18-64 Years
Participants included in this group were aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine alone any time between 31 August 2022 and 30 January 2023.
Group 3a: SIV Alone, 18-64 Years
Participants included in this group were aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received SIV alone any time between 31 August 2022 and 30 January 2023.
Group 1b: Same Day COVID-19 Vaccine and SIV, >= 65 Years
Participants included in this group were aged 65 years and above, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV (enhanced) on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023.
Group 2b: COVID-19 Vaccine Alone, >=65 Years
Participants included in this group were aged 65 years and above, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine alone any time between 31 August 2022 and 30 January 2023.
Group 3b: SIV Alone, >=65 Years
Participants included in this group were aged 65 years and above, who were enrolled in the Optum Clinformatics Database and received SIV (enhanced) alone any time between 31 August 2022 and 30 January 2023.
Overall Study
STARTED
244900
143743
843860
382835
225680
1601978
Overall Study
COMPLETED
244900
143743
843860
382835
225680
1601978
Overall Study
NOT COMPLETED
0
0
0
0
0
0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

This Study Intends to Describe the Characteristics of Patients Given the Pfizer-BioNTech Bivalent mRNA COVID-19 Vaccine and Any Commercially Available Influenza Vaccines at the Same Time Versus at Different Times.

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Group 1a: Same Day COVID-19 Vaccine and SIV, 18-64 Years
n=244900 Participants
Participants included in this group were aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023.
Group 2a: COVID-19 Vaccine Alone, 18-64 Years
n=143743 Participants
Participants included in this group were aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine alone any time between 31 August 2022 and 30 January 2023.
Group 3a: SIV Alone, 18-64 Years
n=843860 Participants
Participants included in this group were aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received SIV alone any time between 31 August 2022 and 30 January 2023.
Group 1b: Same Day COVID-19 Vaccine and SIV, >= 65 Years
n=382835 Participants
Participants included in this group were aged 65 years and above, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV (enhanced) on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023.
Group 2b: COVID-19 Vaccine Alone, >=65 Years
n=225680 Participants
Participants included in this group were aged 65 years and above, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine alone any time between 31 August 2022 and 30 January 2023.
Group 3b: SIV Alone, >=65 Years
n=1601978 Participants
Participants included in this group were aged 65 years and above, who were enrolled in the Optum Clinformatics Database and received SIV (enhanced) alone any time between 31 August 2022 and 30 January 2023.
Total
n=3442996 Participants
Total of all reporting groups
Age, Customized
18-64 years
244900 Participants
n=5 Participants
143743 Participants
n=7 Participants
843860 Participants
n=5 Participants
0 Participants
n=4 Participants
0 Participants
n=21 Participants
0 Participants
n=8 Participants
1232503 Participants
n=8 Participants
Age, Customized
65 years and above
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
382835 Participants
n=4 Participants
225680 Participants
n=21 Participants
1601978 Participants
n=8 Participants
2210493 Participants
n=8 Participants
Sex/Gender, Customized
Female
127108 Participants
n=5 Participants
78029 Participants
n=7 Participants
477067 Participants
n=5 Participants
208166 Participants
n=4 Participants
132345 Participants
n=21 Participants
939216 Participants
n=8 Participants
1961931 Participants
n=8 Participants
Sex/Gender, Customized
Male
117692 Participants
n=5 Participants
65655 Participants
n=7 Participants
366067 Participants
n=5 Participants
174651 Participants
n=4 Participants
93327 Participants
n=21 Participants
661737 Participants
n=8 Participants
1479129 Participants
n=8 Participants
Sex/Gender, Customized
Unknown
100 Participants
n=5 Participants
59 Participants
n=7 Participants
726 Participants
n=5 Participants
18 Participants
n=4 Participants
8 Participants
n=21 Participants
1025 Participants
n=8 Participants
1936 Participants
n=8 Participants
Race/Ethnicity, Customized
Data not available
244900 Participants
n=5 Participants
143743 Participants
n=7 Participants
843860 Participants
n=5 Participants
382835 Participants
n=4 Participants
225680 Participants
n=21 Participants
1601978 Participants
n=8 Participants
3442996 Participants
n=8 Participants

PRIMARY outcome

Timeframe: From Day 15 of vaccination till end of follow-up observation period, from 14-Sep-2022 through 14 February 2023 (approximately 5 months); data was extracted and observed in this retrospective study from 05-May-2023 to 12-May-2023 (8 days)

Population: All eligible participants whose data were observed in this study. This outcome measure presents reporting arms as planned based on the following: participants 18-64 years of age for both models: Model 1 (reporting arms included were co-administration of vaccines on the same day and COVID-19 alone), Model 2 (reporting arms included were co-administration of vaccines on the same day \[excluded participants with unknown/other region\] and SIV alone).

Hospitalization due to any cause is defined as an overnight stay, or longer, in a hospital environment (emergency room, observation unit or in-patient care, or similar facility including admission to a day care facility). To account for imbalance in participant characteristics between the vaccine exposure groups, 2 separate logistic regression models were used. The two models were: Model 1: Same day vs COVID-19 alone, and Model 2: Same day vs Flu (SIV) alone.

Outcome measures

Outcome measures
Measure
Group 1a, Model 1: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=244900 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023.
Group 2a, Model 1: COVID-19 Vaccine Alone, 18-64 Years
n=143743 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only COVID-19 vaccine anytime between 31 August 2022 and 30 January 2023.
Group 1a, Model 2: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=244820 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023. This arm excluded participants with unknown/other region.
Group 3a, Model 2: SIV Alone, 18-64 Years
n=843412 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only SIV anytime between 31 August 2022 and 30 January 2023.
Number of Participants With All Cause Hospitalization Visits: 18-64 Years Old
1838 Participants
705 Participants
1837 Participants
12715 Participants

PRIMARY outcome

Timeframe: From Day 15 of vaccination till end of follow-up observation period, from 14-Sep-2022 through 14 February 2023 (approximately 5 months); data was extracted and observed in this retrospective study from 05-May-2023 to 12-May-2023 (8 days)

Population: All eligible participants whose data were observed in this study. This outcome measure presents reporting arms as planned based on the following: participants \>=65 years of age for both models: Model 1 (reporting arms included were co-administration of vaccines on the same day and COVID-19 alone), Model 2 (reporting arms included were co-administration of vaccines on the same day \[excluded participants with unknown/other region\] and SIV alone).

Hospitalization due to any cause is defined as an overnight stay, or longer, in a hospital environment (emergency room, observation unit or in-patient care, or similar facility including admission to a day care facility). To account for imbalance in participant characteristics between the vaccine exposure groups, 2 separate logistic regression models were used. The two models were: Model 1: Same day vs COVID-19 alone, and Model 2: Same day vs SIV alone.

Outcome measures

Outcome measures
Measure
Group 1a, Model 1: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=382835 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023.
Group 2a, Model 1: COVID-19 Vaccine Alone, 18-64 Years
n=225680 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only COVID-19 vaccine anytime between 31 August 2022 and 30 January 2023.
Group 1a, Model 2: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=382626 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023. This arm excluded participants with unknown/other region.
Group 3a, Model 2: SIV Alone, 18-64 Years
n=1600981 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only SIV anytime between 31 August 2022 and 30 January 2023.
Number of Participants With All Cause Hospitalization Visits: >=65 Years Old
7753 Participants
2719 Participants
7751 Participants
33926 Participants

PRIMARY outcome

Timeframe: From Day 15 of vaccination till end of follow-up observation period, from 14-Sep-2022 through 14 February 2023 (approximately 5 months); data was extracted and observed in this retrospective study from 05-May-2023 to 12-May-2023 (8 days)

Population: All eligible participants whose data were observed in this retrospective observational study. This outcome measure presents reporting arms as planned based on the following: participants 18-64 years and \>=65 years of age for Model 1 (reporting arms included were co-administration of vaccines on the same day and COVID-19 alone).

Hospitalization, emergency department or urgent care visits with COVID-19 diagnosis code (International Classification of Diseases, 10th revision \[ICD-10-CM\]: U07.1) in any position. To account for imbalance in participant characteristics between the vaccine exposure groups, 2 separate logistic regression models were used. The two models were: Model 1: Same day vs COVID-19 alone, and Model 2: Same day vs SIV alone. In this outcome measure data is reported for Model 1: Same day vs COVID-19 alone.

Outcome measures

Outcome measures
Measure
Group 1a, Model 1: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=244900 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023.
Group 2a, Model 1: COVID-19 Vaccine Alone, 18-64 Years
n=143743 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only COVID-19 vaccine anytime between 31 August 2022 and 30 January 2023.
Group 1a, Model 2: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=382835 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023. This arm excluded participants with unknown/other region.
Group 3a, Model 2: SIV Alone, 18-64 Years
n=225680 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only SIV anytime between 31 August 2022 and 30 January 2023.
Number of Participants With Composite Coronavirus Disease (COVID-19)-Related Hospitalization, Emergency Department or Urgent Care Visits: Same Day Versus COVID-19 Alone
181 Participants
55 Participants
2085 Participants
684 Participants

PRIMARY outcome

Timeframe: From Day 15 of vaccination till end of follow-up observation period, from 14-Sep-2022 through 14 February 2023 (approximately 5 months); data was extracted and observed in this retrospective study from 05-May-2023 to 12-May-2023 (8 days)

Population: All eligible participants whose data were observed in this retrospective observational study. This outcome measure presents reporting arms as planned based on the following: participants 18-64 years and \>=65 years of age for Model 2 (reporting arms included were co-administration of vaccines on the same day \[excluded participants with unknown/other region\] and SIV alone).

Hospitalization, emergency department or urgent care visits with Influenza diagnosis code (ICD-10-CM: J09.X, J10.X, J11.X) in any position. To account for imbalance in participant characteristics between the vaccine exposure groups, 2 separate logistic regression models were used. The two models were: Model 1: Same day vs COVID-19 alone, and Model 2: Same day vs SIV alone. In this outcome measure data is reported for Model 2: Same day vs SIV alone.

Outcome measures

Outcome measures
Measure
Group 1a, Model 1: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=244820 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023.
Group 2a, Model 1: COVID-19 Vaccine Alone, 18-64 Years
n=843412 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only COVID-19 vaccine anytime between 31 August 2022 and 30 January 2023.
Group 1a, Model 2: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=382626 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023. This arm excluded participants with unknown/other region.
Group 3a, Model 2: SIV Alone, 18-64 Years
n=1600981 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only SIV anytime between 31 August 2022 and 30 January 2023.
Number of Participants With Composite Influenza Related Hospitalization, Emergency Department or Urgent Care Visits: Same Day Versus SIV Alone
145 Participants
770 Participants
953 Participants
3936 Participants

PRIMARY outcome

Timeframe: From Day 15 of vaccination till end of follow-up observation period, (from 14-Sep-2022 through 14 February 2023 (approximately 5 months); data was extracted and observed in this retrospective study from 05-May-2023 to 12-May-2023 (8 days)

Population: All eligible participants whose data were observed in this retrospective observational study. This outcome measure presents reporting arms as planned based on the following: participants 18-64 years and \>=65 years of age for Model 1 (reporting arms included were co-administration of vaccines on the same day and COVID-19 alone).

COVID-19 diagnosis code (ICD-10-CM: U07.1) in any position. An outpatient visit refers to any encounter that is in the outpatient setting. To account for imbalance in participant characteristics between the vaccine exposure groups, 2 separate logistic regression models were used. The two models were: Model 1: Same day vs COVID-19 alone, and Model 2: Same day vs SIV alone. In this outcome measure data is reported for Model 1: Same day vs COVID-19 alone.

Outcome measures

Outcome measures
Measure
Group 1a, Model 1: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=244900 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023.
Group 2a, Model 1: COVID-19 Vaccine Alone, 18-64 Years
n=143743 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only COVID-19 vaccine anytime between 31 August 2022 and 30 January 2023.
Group 1a, Model 2: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=382835 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023. This arm excluded participants with unknown/other region.
Group 3a, Model 2: SIV Alone, 18-64 Years
n=225680 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only SIV anytime between 31 August 2022 and 30 January 2023.
Number of Participants With COVID-19 Related Outpatient Visits: Same Day Versus COVID-19 Alone
3513 Participants
1399 Participants
6473 Participants
2268 Participants

PRIMARY outcome

Timeframe: From Day 15 of vaccination till end of follow-up observation period, from 14-Sep-2022 through 14 February 2023 (approximately 5 months); data was extracted and observed in this retrospective study from 05-May-2023 to 12-May-2023 (8 days)

Population: All eligible participants whose data were observed in this retrospective observational study. This outcome measure presents reporting arms as planned based on the following: participants 18-64 years and \>=65 years of age for Model 2 (reporting arms included were co-administration of vaccines on the same day \[excluded participants with unknown/other region\] and SIV alone).

Influenza diagnosis code (ICD-10-CM: J09.X, J10.X, J11.X) in any position. An outpatient visit refers to any encounter that is in the outpatient setting. To account for imbalance in participant characteristics between the vaccine exposure groups, 2 separate logistic regression models were used. The two models were: Model 1: Same day vs COVID-19 alone, and Model 2: Same day vs SIV alone. In this outcome measure data is reported for Model 2: Same day vs SIV alone.

Outcome measures

Outcome measures
Measure
Group 1a, Model 1: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=244820 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023.
Group 2a, Model 1: COVID-19 Vaccine Alone, 18-64 Years
n=843412 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only COVID-19 vaccine anytime between 31 August 2022 and 30 January 2023.
Group 1a, Model 2: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=382626 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023. This arm excluded participants with unknown/other region.
Group 3a, Model 2: SIV Alone, 18-64 Years
n=1600981 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only SIV anytime between 31 August 2022 and 30 January 2023.
Number of Participants With Influenza-Related Outpatient Visits: Same Day Versus SIV Alone
1346 Participants
6200 Participants
1457 Participants
6396 Participants

PRIMARY outcome

Timeframe: From Day 15 of vaccination till end of follow-up observation period, from 14-Sep-2022 through 14 February 2023 (approximately 5 months); data was extracted and observed in this retrospective study from 05-May-2023 to 12-May-2023 (8 days)

Population: All eligible participants whose data were observed in this retrospective observational study. This outcome measure presents reporting arms as planned based on the following: participants 18-64 years and \>=65 years of age for Model 1 (reporting arms included were co-administration of vaccines on the same day and COVID-19 alone).

COVID-19 diagnosis code (ICD-10-CM: U07.1) in any position. To account for imbalance in participant characteristics between the vaccine exposure groups, 2 separate logistic regression models were used. The two models were: Model 1: Same day vs COVID-19 alone, and Model 2: Same day vs SIV alone. In this outcome measure data is reported for Model 1: Same day vs COVID-19 alone.

Outcome measures

Outcome measures
Measure
Group 1a, Model 1: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=244900 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023.
Group 2a, Model 1: COVID-19 Vaccine Alone, 18-64 Years
n=143743 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only COVID-19 vaccine anytime between 31 August 2022 and 30 January 2023.
Group 1a, Model 2: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=382835 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023. This arm excluded participants with unknown/other region.
Group 3a, Model 2: SIV Alone, 18-64 Years
n=225680 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only SIV anytime between 31 August 2022 and 30 January 2023.
Number of Participants With COVID-19 Related Hospitalization Visits: Same Day Versus COVID-19 Alone
57 Participants
14 Participants
452 Participants
164 Participants

PRIMARY outcome

Timeframe: From Day 15 of vaccination till end of follow-up observation period, (from 14-Sep-2022 through 14 February 2023 (approximately 5 months); data was extracted and observed in this retrospective study from 05-May-2023 to 12-May-2023 (8 days)

Population: All eligible participants whose data were observed in this retrospective observational study. This outcome measure presents reporting arms as planned based on the following: participants 18-64 years and \>=65 years of age for Model 2 (reporting arms included were co-administration of vaccines on the same day \[excluded participants with unknown/other region\] and SIV alone).

Influenza diagnosis code (ICD-10-CM: J09.X, J10.X, J11.X) in any position. To account for imbalance in participant characteristics between the vaccine exposure groups, 2 separate logistic regression models were used. The two models were: Model 1: Same day vs COVID-19 alone, and Model 2: Same day vs SIV alone. In this outcome measure data is reported for Model 2: Same day vs SIV alone.

Outcome measures

Outcome measures
Measure
Group 1a, Model 1: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=244820 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023.
Group 2a, Model 1: COVID-19 Vaccine Alone, 18-64 Years
n=843412 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only COVID-19 vaccine anytime between 31 August 2022 and 30 January 2023.
Group 1a, Model 2: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=382626 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023. This arm excluded participants with unknown/other region.
Group 3a, Model 2: SIV Alone, 18-64 Years
n=1600981 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only SIV anytime between 31 August 2022 and 30 January 2023.
Number of Participants With Influenza Related Hospitalization Visits: Same Day Versus SIV Alone
47 Participants
228 Participants
232 Participants
1164 Participants

PRIMARY outcome

Timeframe: From Day 15 of vaccination till end of follow-up observation period, from 14-Sep-2022 through 14 February 2023 (approximately 5 months); data was extracted and observed in this retrospective study from 05-May-2023 to 12-May-2023 (8 days)

Population: All eligible participants whose data were observed in this retrospective observational study. This outcome measure presents reporting arms as planned based on the following: participants 18-64 years and \>=65 years of age for Model 1 (reporting arms included were co-administration of vaccines on the same day and COVID-19 alone).

COVID-19 diagnosis code (ICD-10-CM: U07.1) in any position. To account for imbalance in participant characteristics between the vaccine exposure groups, 2 separate logistic regression models were used. The two models were: Model 1: Same day vs COVID-19 alone, and Model 2: Same day vs SIV alone. In this outcome measure data is reported for Model 1: Same day vs COVID-19 alone.

Outcome measures

Outcome measures
Measure
Group 1a, Model 1: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=244900 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023.
Group 2a, Model 1: COVID-19 Vaccine Alone, 18-64 Years
n=143743 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only COVID-19 vaccine anytime between 31 August 2022 and 30 January 2023.
Group 1a, Model 2: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=382835 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023. This arm excluded participants with unknown/other region.
Group 3a, Model 2: SIV Alone, 18-64 Years
n=225680 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only SIV anytime between 31 August 2022 and 30 January 2023.
Number of Participants With COVID-19-Related Emergency Department Visits/ Urgent Care Visits: Same Day Versus COVID-19 Alone
127 Participants
41 Participants
1674 Participants
535 Participants

PRIMARY outcome

Timeframe: From Day 15 of vaccination till end of follow-up observation period, (from 14-Sep-2022 through 14 February 2023 (approximately 5 months); data was extracted and observed in this retrospective study from 05-May-2023 to 12-May-2023 (8 days)

Population: All eligible participants whose data were observed in this retrospective observational study. This outcome measure presents reporting arms as planned based on the following: participants 18-64 years and \>=65 years of age for Model 2 (reporting arms included were co-administration of vaccines on the same day \[excluded participants with unknown/other region\] and SIV alone).

Influenza diagnosis code (ICD-10-CM: J09.X, J10.X, J11.X) in any position. To account for imbalance in participant characteristics between the vaccine exposure groups, 2 separate logistic regression models were used. The two models were: Model 1: Same day vs COVID-19 alone, and Model 2: Same day vs SIV alone. In this outcome measure data is reported for Model 2: Same day vs SIV alone.

Outcome measures

Outcome measures
Measure
Group 1a, Model 1: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=244820 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023.
Group 2a, Model 1: COVID-19 Vaccine Alone, 18-64 Years
n=843412 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only COVID-19 vaccine anytime between 31 August 2022 and 30 January 2023.
Group 1a, Model 2: Same Day (COVID-19 Vaccine and SIV), 18-64 Years
n=382626 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received COVID-19 vaccine and SIV on the same day (co-administration) anytime between 31 August 2022 and 30 January 2023. This arm excluded participants with unknown/other region.
Group 3a, Model 2: SIV Alone, 18-64 Years
n=1600981 Participants
Participants aged 18-64 years, who were enrolled in the Optum Clinformatics Database and received only SIV anytime between 31 August 2022 and 30 January 2023.
Number of Participants With Influenza-Related Emergency Department Visits/ Urgent Care Visits: Same Day Versus SIV Alone
100 Participants
558 Participants
736 Participants
2870 Participants

Adverse Events

Group 1a: Same Day COVID-19 Vaccine and SIV, 18-64 Years

Serious events: 0 serious events
Other events: 0 other events
Deaths: 110 deaths

Group 2a: COVID-19 Vaccine Alone, 18-64 Years

Serious events: 0 serious events
Other events: 0 other events
Deaths: 63 deaths

Group 3a: SIV Alone, 18-64 Years

Serious events: 0 serious events
Other events: 0 other events
Deaths: 794 deaths

Group 1b: Same Day COVID-19 Vaccine and SIV, >= 65 Years

Serious events: 0 serious events
Other events: 0 other events
Deaths: 2160 deaths

Group 2b: COVID-19 Vaccine Alone, >=65 Years

Serious events: 0 serious events
Other events: 0 other events
Deaths: 1402 deaths

Group 3b: SIV Alone, >=65 Years

Serious events: 0 serious events
Other events: 0 other events
Deaths: 12031 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Pfizer ClinicalTrials.gov Call Center

Pfizer Inc.

Phone: 1-800-718-1021

Results disclosure agreements

  • Principal investigator is a sponsor employee Pfizer has the right to review disclosures, requesting a delay of less than 60 days. Investigator will postpone single center publications until after disclosure of pooled data (all sites), less than 12 months from study completion/termination at all participating sites. Investigator may not disclose previously undisclosed confidential information other than study results.
  • Publication restrictions are in place

Restriction type: OTHER