Trial Outcomes & Findings for Flublok v. Standard Dose Vaccine Effectiveness Among Kaiser Permanente Northern California Adults 18-64 Years (NCT NCT03694392)
NCT ID: NCT03694392
Last Updated: 2025-04-08
Results Overview
Patients who receive either Flublok or SD-IIV will be retroactively assessed for whether they had a PCR-confirmed positive influenza test (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30).
Recruitment status
COMPLETED
Target enrollment
2776278 participants
Primary outcome timeframe
Up to 8 months
Results posted on
2025-04-08
Participant Flow
Participant milestones
| Measure |
Flublok Recipients
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Overall Study
STARTED
|
1018043
|
1758235
|
|
Overall Study
COMPLETED
|
632962
|
997366
|
|
Overall Study
NOT COMPLETED
|
385081
|
760869
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
Flublok v. Standard Dose Vaccine Effectiveness Among Kaiser Permanente Northern California Adults 18-64 Years
Baseline characteristics by cohort
| Measure |
Flublok Recipients
n=632962 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=997366 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
Total
n=1630328 Participants
Total of all reporting groups
|
|---|---|---|---|
|
Age, Categorical
<=18 years
|
0 Participants
n=99 Participants
|
0 Participants
n=107 Participants
|
0 Participants
n=206 Participants
|
|
Age, Categorical
Between 18 and 65 years
|
632962 Participants
n=99 Participants
|
997366 Participants
n=107 Participants
|
1630328 Participants
n=206 Participants
|
|
Age, Categorical
>=65 years
|
0 Participants
n=99 Participants
|
0 Participants
n=107 Participants
|
0 Participants
n=206 Participants
|
|
Sex: Female, Male
Female
|
363921 Participants
n=99 Participants
|
585482 Participants
n=107 Participants
|
949403 Participants
n=206 Participants
|
|
Sex: Female, Male
Male
|
269041 Participants
n=99 Participants
|
411884 Participants
n=107 Participants
|
680925 Participants
n=206 Participants
|
|
Race/Ethnicity, Customized
White
|
275117 Participants
n=99 Participants
|
420570 Participants
n=107 Participants
|
695687 Participants
n=206 Participants
|
|
Race/Ethnicity, Customized
Black
|
27601 Participants
n=99 Participants
|
45674 Participants
n=107 Participants
|
73275 Participants
n=206 Participants
|
|
Race/Ethnicity, Customized
Asian
|
159104 Participants
n=99 Participants
|
255008 Participants
n=107 Participants
|
414112 Participants
n=206 Participants
|
|
Race/Ethnicity, Customized
Pacific Islander
|
4824 Participants
n=99 Participants
|
7499 Participants
n=107 Participants
|
12323 Participants
n=206 Participants
|
|
Race/Ethnicity, Customized
Native American
|
2908 Participants
n=99 Participants
|
4635 Participants
n=107 Participants
|
7543 Participants
n=206 Participants
|
|
Race/Ethnicity, Customized
Multiracial
|
16229 Participants
n=99 Participants
|
25946 Participants
n=107 Participants
|
42175 Participants
n=206 Participants
|
|
Race/Ethnicity, Customized
Unknown/Other
|
147179 Participants
n=99 Participants
|
238034 Participants
n=107 Participants
|
385213 Participants
n=206 Participants
|
|
Region of Enrollment
United States
|
632962 participants
n=99 Participants
|
997366 participants
n=107 Participants
|
1630328 participants
n=206 Participants
|
|
History of asthma
|
86127 Participants
n=99 Participants
|
132550 Participants
n=107 Participants
|
218677 Participants
n=206 Participants
|
|
History of diabetes
|
67026 Participants
n=99 Participants
|
97192 Participants
n=107 Participants
|
164218 Participants
n=206 Participants
|
|
History of chronic obstructive pulmonary disease
|
6174 Participants
n=99 Participants
|
8563 Participants
n=107 Participants
|
14737 Participants
n=206 Participants
|
|
History of coronary heart disease
|
11947 Participants
n=99 Participants
|
16902 Participants
n=107 Participants
|
28849 Participants
n=206 Participants
|
|
Receipt of influenza vaccine in previous year
|
414500 Participants
n=99 Participants
|
640263 Participants
n=107 Participants
|
1054763 Participants
n=206 Participants
|
|
Charlson Comorbidity Index
No Charlson comorbidities
|
508118 Participants
n=99 Participants
|
812879 Participants
n=107 Participants
|
1320997 Participants
n=206 Participants
|
|
Charlson Comorbidity Index
CCI=1
|
81980 Participants
n=99 Participants
|
122562 Participants
n=107 Participants
|
204542 Participants
n=206 Participants
|
|
Charlson Comorbidity Index
CCI≥2
|
42864 Participants
n=99 Participants
|
61925 Participants
n=107 Participants
|
104789 Participants
n=206 Participants
|
|
Body mass index
0 - < 18.5 kg/m²
|
7819 Participants
n=99 Participants
|
12311 Participants
n=107 Participants
|
20130 Participants
n=206 Participants
|
|
Body mass index
18.5 - < 25 kg/m²
|
188431 Participants
n=99 Participants
|
306194 Participants
n=107 Participants
|
494625 Participants
n=206 Participants
|
|
Body mass index
25 - < 30 kg/m²
|
206663 Participants
n=99 Participants
|
323624 Participants
n=107 Participants
|
530287 Participants
n=206 Participants
|
|
Body mass index
≥ 30 kg/m²
|
209817 Participants
n=99 Participants
|
321607 Participants
n=107 Participants
|
531424 Participants
n=206 Participants
|
|
Body mass index
None
|
20232 Participants
n=99 Participants
|
33630 Participants
n=107 Participants
|
53862 Participants
n=206 Participants
|
|
Number of weeks with outpatient visits in prior year
0
|
57602 Participants
n=99 Participants
|
92349 Participants
n=107 Participants
|
149951 Participants
n=206 Participants
|
|
Number of weeks with outpatient visits in prior year
1-3
|
270701 Participants
n=99 Participants
|
427043 Participants
n=107 Participants
|
697744 Participants
n=206 Participants
|
|
Number of weeks with outpatient visits in prior year
4-7
|
165444 Participants
n=99 Participants
|
256965 Participants
n=107 Participants
|
422409 Participants
n=206 Participants
|
|
Number of weeks with outpatient visits in prior year
≥8
|
139215 Participants
n=99 Participants
|
221009 Participants
n=107 Participants
|
360224 Participants
n=206 Participants
|
|
Number of inpatient stays in prior year
0
|
573712 Participants
n=99 Participants
|
902365 Participants
n=107 Participants
|
1476077 Participants
n=206 Participants
|
|
Number of inpatient stays in prior year
1
|
44860 Participants
n=99 Participants
|
71208 Participants
n=107 Participants
|
116068 Participants
n=206 Participants
|
|
Number of inpatient stays in prior year
2
|
9707 Participants
n=99 Participants
|
15896 Participants
n=107 Participants
|
25603 Participants
n=206 Participants
|
|
Number of inpatient stays in prior year
3
|
2885 Participants
n=99 Participants
|
4735 Participants
n=107 Participants
|
7620 Participants
n=206 Participants
|
|
Number of inpatient stays in prior year
≥4
|
1798 Participants
n=99 Participants
|
3162 Participants
n=107 Participants
|
4960 Participants
n=206 Participants
|
|
Prior membership
<1 year
|
78004 Participants
n=99 Participants
|
127160 Participants
n=107 Participants
|
205164 Participants
n=206 Participants
|
|
Prior membership
1 to <2 years
|
62407 Participants
n=99 Participants
|
100315 Participants
n=107 Participants
|
162722 Participants
n=206 Participants
|
|
Prior membership
2 to <3 years
|
52678 Participants
n=99 Participants
|
84938 Participants
n=107 Participants
|
137616 Participants
n=206 Participants
|
|
Prior membership
3 to <4 years
|
45919 Participants
n=99 Participants
|
74028 Participants
n=107 Participants
|
119947 Participants
n=206 Participants
|
|
Prior membership
4 to <5 years
|
41545 Participants
n=99 Participants
|
66292 Participants
n=107 Participants
|
107837 Participants
n=206 Participants
|
|
Prior membership
≥5 years
|
352409 Participants
n=99 Participants
|
544633 Participants
n=107 Participants
|
897042 Participants
n=206 Participants
|
PRIMARY outcome
Timeframe: Up to 8 monthsPatients who receive either Flublok or SD-IIV will be retroactively assessed for whether they had a PCR-confirmed positive influenza test (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30).
Outcome measures
| Measure |
Flublok Recipients
n=279400 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=395852 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Number of Adults 50-64 Years Old With Polymerase-chain Reaction (PCR) Confirmed Influenza Tests
|
559 participants
|
925 participants
|
SECONDARY outcome
Timeframe: Up to 8 monthsPatients who receive either Flublok or SD-IIV will be retroactively assessed for whether they had an inpatient stay and had a PCR-confirmed positive influenza test (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30).
Outcome measures
| Measure |
Flublok Recipients
n=279400 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=395852 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Number of Adults 50-64 Years Old Hospitalized With PCR-confirmed Influenza
|
95 participants
|
153 participants
|
SECONDARY outcome
Timeframe: Up to 8 monthsPatients who receive either Flublok or SD-IIV will be retroactively assessed for whether they had an inpatient stay for community-acquired pneumonia (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30).
Outcome measures
| Measure |
Flublok Recipients
n=279400 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=395852 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Number of Adults 50-64 Years Old Hospitalized With Community-acquired Pneumonia
|
106 Participants
|
183 Participants
|
SECONDARY outcome
Timeframe: Up to 8 monthsPatients who receive either Flublok or SD-IIV will be retroactively assessed for whether they had an inpatient stay for cardio-respiratory events (e.g., pneumonia, other lower respiratory infections, acute myocardial infarction, congestive heart failure, stroke) (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30).
Outcome measures
| Measure |
Flublok Recipients
n=279400 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=395852 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Number of Adults 50-64 Years Old Hospitalized With Cardio-respiratory Events
|
631 Participants
|
890 Participants
|
SECONDARY outcome
Timeframe: Up to 8 monthsPatients who receive either Flublok or SD-IIV will be retroactively assessed for whether they had a PCR-confirmed positive influenza A test (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30).
Outcome measures
| Measure |
Flublok Recipients
n=279400 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=395852 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Number of Adults 50-64 Years Old With Polymerase-chain Reaction (PCR) Confirmed Influenza A Tests
|
522 participants
|
862 participants
|
SECONDARY outcome
Timeframe: Up to 8 monthsPatients who receive either Flublok or SD-IIV will be retroactively assessed for whether they had a PCR-confirmed positive influenza B test (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30).
Outcome measures
| Measure |
Flublok Recipients
n=279400 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=395852 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Number of Adults 50-64 Years Old With Polymerase-chain Reaction (PCR) Confirmed Influenza B Tests
|
37 participants
|
64 participants
|
OTHER_PRE_SPECIFIED outcome
Timeframe: Up to 8 monthsPatients who receive either Flublok or SD-IIV will be retroactively assessed for whether they had an inpatient stay for community-acquired pneumonia (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30).
Outcome measures
| Measure |
Flublok Recipients
n=353562 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=601514 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Number of Adults 18-49 Years Old Hospitalized With Community-acquired Pneumonia
|
37 Participants
|
49 Participants
|
OTHER_PRE_SPECIFIED outcome
Timeframe: Up to 8 monthsPatients who receive either Flublok or SD-IIV will be retroactively assessed (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30) for influenza-like illness (ILI) International Classification of Diseases, 10th Edition (and absence of a negative lab-confirmed influenza)
Outcome measures
| Measure |
Flublok Recipients
n=279400 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=395852 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Number of Adults 50-64 Years Old With Influenza-Like Illness (ILI)
|
1826 Participants
|
2871 Participants
|
OTHER_PRE_SPECIFIED outcome
Timeframe: Up to 8 monthsPatients who receive either Flublok or SD-IIV will be retroactively assessed (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30) for all-cause hospitalizations
Outcome measures
| Measure |
Flublok Recipients
n=279400 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=395852 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Number of Adults 50-64 Years Old With All-Cause-Hospitalizations
|
4308 Participants
|
6005 Participants
|
OTHER_PRE_SPECIFIED outcome
Timeframe: Up to 8 monthsPatients who receive either Flublok or SD-IIV will be retroactively assessed (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30) for all-cause mortality
Outcome measures
| Measure |
Flublok Recipients
n=279400 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=395852 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Number of Adults 50-64 Years Old With All-Cause Mortality
|
286 Participants
|
422 Participants
|
OTHER_PRE_SPECIFIED outcome
Timeframe: Up to 8 monthsPatients who receive either Flublok or SD-IIV will be retroactively assessed for whether they had a PCR-confirmed positive influenza test (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30).
Outcome measures
| Measure |
Flublok Recipients
n=353562 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=601514 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Number of Adults 18-49 Years Old With Polymerase-chain Reaction (PCR) Confirmed Influenza Tests
|
827 participants
|
1510 participants
|
OTHER_PRE_SPECIFIED outcome
Timeframe: Up to 8 monthsPatients who receive either Flublok or SD-IIV will be retroactively assessed for whether they had an inpatient stay and had a PCR-confirmed positive influenza test (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30).
Outcome measures
| Measure |
Flublok Recipients
n=353562 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=601514 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Number of Adults 18-49 Years Old Hospitalized With PCR-confirmed Influenza
|
48 participants
|
88 participants
|
OTHER_PRE_SPECIFIED outcome
Timeframe: Up to 8 monthsPatients who receive either Flublok or SD-IIV will be retroactively assessed for whether they had an inpatient stay for cardio-respiratory events (e.g., pneumonia, other lower respiratory infections, acute myocardial infarction, congestive heart failure, stroke) (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30).
Outcome measures
| Measure |
Flublok Recipients
n=353562 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=601514 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Number of Adults 18-49 Years Old Hospitalized With Cardio-respiratory Events
|
133 Participants
|
208 Participants
|
OTHER_PRE_SPECIFIED outcome
Timeframe: Up to 8 monthsPatients who receive either Flublok or SD-IIV will be retroactively assessed (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30) for influenza-like illness (ILI) International Classification of Diseases, 10th Edition (and absence of a negative lab-confirmed influenza)
Outcome measures
| Measure |
Flublok Recipients
n=353562 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=601514 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Number of Adults 18-49 Years Old With Influenza-Like Illness (ILI)
|
2904 Participants
|
5434 Participants
|
OTHER_PRE_SPECIFIED outcome
Timeframe: Up to 8 monthsPatients who receive either Flublok or SD-IIV will be retroactively assessed (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30) for all-cause hospitalizations
Outcome measures
| Measure |
Flublok Recipients
n=353562 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=601514 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Number of Adults 18-49 Years Old With All-Cause-Hospitalizations
|
1858 Participants
|
2950 Participants
|
OTHER_PRE_SPECIFIED outcome
Timeframe: Up to 8 monthsPatients who receive either Flublok or SD-IIV will be retroactively assessed (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30) for all-cause mortality
Outcome measures
| Measure |
Flublok Recipients
n=353562 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=601514 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Number of Adults 18-49 Years Old With All-Cause Mortality
|
66 Participants
|
79 Participants
|
OTHER_PRE_SPECIFIED outcome
Timeframe: Up to 8 monthsPatients who receive either Flublok or SD-IIV will be retroactively assessed for whether they had a PCR-confirmed positive influenza A test (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30).
Outcome measures
| Measure |
Flublok Recipients
n=353562 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=601514 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Number of Adults 18-49 Years Old With Polymerase-chain Reaction (PCR) Confirmed Influenza A Tests
|
682 participants
|
1282 participants
|
OTHER_PRE_SPECIFIED outcome
Timeframe: Up to 8 monthsPatients who receive either Flublok or SD-IIV will be retroactively assessed for whether they had a PCR-confirmed positive influenza B test (≥14 days after vaccination) as recorded in their electronic medical record by the end of the influenza season (April 30).
Outcome measures
| Measure |
Flublok Recipients
n=353562 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive Flublok Quadrivalent vaccine.
Flublok Quadrivalent: Flublok Quadrivalent vaccine is a recombinant hemagglutinin influenza vaccine indicated for active immunization against disease caused by influenza A subtype viruses and type B viruses contained in the vaccine for adults 18 years of age and older. Use of recombinant DNA techniques to produce vaccine antigen expressed in cell culture is a method that avoids growing the influenza viruses in embryonated hen's eggs.
|
SD-IIV Recipients
n=601514 Participants
Kaiser Permanente Northern California members aged 18-64 years who receive standard dose inactivated influenza vaccine (SD-IIV).
Standard Dose Inactivated Influenza Vaccine (SD-IIV): For the 2018-2019, 2019-2020, and 2020-2021 flu seasons, the primary SD-IIVs used will be Fluarix Quadrivalent and Flulaval Quadrivalent.
|
|---|---|---|
|
Number of Adults 18-49 Years Old With Polymerase-chain Reaction (PCR) Confirmed Influenza B Tests
|
146 participants
|
231 participants
|
Adverse Events
Flublok Recipients
Serious events: 0 serious events
Other events: 0 other events
Deaths: 352 deaths
SD-IIV Recipients
Serious events: 0 serious events
Other events: 0 other events
Deaths: 501 deaths
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Amber Hsiao Hyman, Senior Research Project Manger
Kaiser Permanente Vaccine Study Center
Phone: 510-267-7517
Email: [email protected]
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place