Pfizer-BioNTech COVID-19 BNT162b2 Vaccine Effectiveness Study - Kaiser Permanente Southern California
Study Details
Study Description
Brief Summary
The primary objective of this study is to determine the vaccine effectiveness of 2 doses of Pfizer-BioNTech BNT162b2 vaccine against COVID-19-associated hospitalization. There will be a large retrospective database study using two parallel study designs: a test-negative case-control design and a retrospective cohort design. Exploratory analyses of VE estimates by strain type will be conducted.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
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Detailed Description
The primary objective of the study is to estimate vaccine effectiveness (VE) of 2 doses of Pfizer's BNT162b2 vaccine against acute respiratory illness (ARI) requiring hospitalization due to SARS-CoV-2 infection among KPSC members eligible for vaccination. VE will be evaluated using a test-negative design (TND), including all KPSC patients eligible for vaccination who are admitted to the hospital with (ARI) after 14 December 2020 (date of first vaccinations at KPSC), and who receive a PCR test for SARS-CoV-2. Secondary and exploratory objectives may examine VE for 1 dose vaccination, at least 1 dose, >2 doses as well as against ED admission, specific variants, mixed dosing schedules, durability, age cut-offs to align with regulatory authorizations/approvals and other populations of interest. Additionally, we will estimate VE using a full cohort design, including all KPSC members eligible for vaccination.
To assess VE, we propose a large retrospective database study using two parallel study de-signs: a test-negative case-control design and a retrospective cohort design. The TND will assess VE against COVID-19 hospitalization (primary endpoint) and ED admission. The retrospective cohort analysis may assess VE against COVID-19 hospitalization (primary), ICU admission, death, ED admission, and outpatient disease (with no subsequent hospitalization within 14 days). We may further conduct additional analyses of VE estimates by various patient characteristics and strain type
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Fully vaccinated 2 doses of BNT162b2 received with ≥7 days between receipt of the 2nd dose and the index date. This group will serve as the 'exposed' group evaluated in the primary objective. |
Biological: Primary Exposure Status of Pfizer-BioNTech COVID-19 Vaccine
Pfizer-BioNTech COVID-19 vaccine
Other Names:
|
| Partially vaccinated 1 dose (only) of BNT162b2 received with ≥14 days between receipt of the 1st dose and the index date. |
Biological: Primary Exposure Status of Pfizer-BioNTech COVID-19 Vaccine
Pfizer-BioNTech COVID-19 vaccine
Other Names:
|
| Ever vaccinated ≥1 dose of BNT162b2 received with ≥14 days between index date and receipt of the 1st dose |
Biological: Primary Exposure Status of Pfizer-BioNTech COVID-19 Vaccine
Pfizer-BioNTech COVID-19 vaccine
Other Names:
|
| Never vaccinated never received BNT162b2. This group will serve as the reference exposure group (i.e., 'unexposed' group) in all VE analyses |
Biological: Primary Exposure Status of Pfizer-BioNTech COVID-19 Vaccine
Pfizer-BioNTech COVID-19 vaccine
Other Names:
|
Outcome Measures
Primary Outcome Measures
- VE calculated as 1 minus the odds ratio (OR) comparing the odds of being fully vaccinated (2 doses) with BNT162b2 for hospitalized cases and controls, multiplied by 100%. [Dec 2020-Apr 2022, Through study completion, average of one month]
To estimate the effectiveness of 2 doses of BNT162b2 against hospitalization due to SARS-CoV-2 infection
Secondary Outcome Measures
- VE calculated as 1 minus the OR comparing the odds of being fully vaccinated (2 doses) with BNT162b2 for ED cases and controls, multiplied by 100%. [Through study completion, average of one month]
To estimate the effectiveness of 2 doses of BNT162b2 against ED admission (without subsequent hospitalization) ED admission due to SARS-CoV-2 infection
- VE calculated as 1 minus the HR comparing the incidence of 2 doses with BNT162b2 for ICU ad-mission due to SARS-CoV-2 infection and not, multiplied by 100%. [Through study completion, average of one month]
To estimate the effectiveness of 2 doses of BNT162b2 against ICU admission due to SARS-CoV-2 infection
- VE calculated as 1 minus the HR comparing the incidence of (2 doses with BNT162b2 for death due to SARS-CoV-2 infection and not, multiplied by 100%. [Through study completion, average of one month]
To estimate the effectiveness of 2 doses of BNT162b2 against death due to SARS-CoV-2 infection
- VE calculated as 1 minus the HR comparing the incidence of 2 doses with BNT162b2 for COVID-19 outpatient visits (without subsequent hospitalization within 14 days) due to SARS-CoV-2 infection and not, multiplied by 100%. [Through study completion, average of one month]
To estimate the effectiveness of 2 doses of BNT162b2 against COVID-19 outpatient visits (without subsequent hospitalization within 14 days) due to SARS-CoV-2 infection
- VE calculated as 1 minus the HR comparing the incidence of only 1 dose of BNT162b2 for hospitalization, ED visit, death, and COVID-19 outpatient visits (without hospitalization within 14 days) due to SARS-CoV-2 infection and not, multiplied by 100%. [Through study completion, average of one month]
To describe the effectiveness of only 1 dose of BNT162b2 (i.e., partially vaccinated) against hospitalization, ED admission, ICU admission, death, and outpatient visits (without subsequent hospitalization within 14 days) due to SARS-CoV-2 infection
- VE calculated as 1 minus the HR comparing the incidence ≥1 dose of BNT162b2 for hospitalization, ED visit, death, and COVID-19 outpatient visits (without subsequent hospitaliza-tion within 14 days) due to SARS-CoV-2 infection and not, multiplied by 100%. [Through study completion, average of one month]
To describe the effectiveness of ≥1 dose of BNT162b2 (i.e., ever vaccinated) against hospitalization, ICU admission, ED admission, death, and outpatient visits (without subsequent hospitalization within 14 days) due to SARS-CoV-2 infection
- VE calculated as 1 minus the HR comparing the incidence of >2 doses of BNT162b2 for hospitaliza-tion, ED visit, death, and COVID-19 outpatient vis-its (without subsequent hospitalization within 14 days) due to SARS-CoV-2 infection, multiplied by 100%. [Through study completion, average of one month]
To describe the effectiveness of >2 doses of BNT162b2 against hospitalization, ED admission, ICU admission, death, and outpatient visits (without subsequent hospital-ization within 14 days) due to SARS-CoV-2 infection.
Eligibility Criteria
Criteria
Inclusion Criteria for Test Negative Design
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KPSC patients eligible to receive BNT162b2 who are admitted to the hospital (primary objective and some secondary objectives) with acute respiratory infection (ARI; International Classification of Diseases (ICD) codes) after 14 December 2020 (date of first vaccinations at KPSC), and who receive a PCR test for SARS-CoV-2.
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For secondary objectives estimating VE against ED admission, the TND will include KPSC patients eligible to receive BNT162b2 who present to the ED with ARI after 14 December 2020, and who receive a PCR test for SARS-CoV-2.
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We will include membership requirement of 1 year prior to index date, which is defined as the date of hospitalization or ED admission (allowing 31-day administrative gap), to facilitate accurate capture of comorbid conditions.
Inclusion Criteria for Cohort Design-
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All KPSC members as of 14 December 2020 (date of first Pfizer vaccination at KPSC) eligible to receive BNT162b2.
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For the cohort study, patients must have at least 1 year of membership (allowing 31-day administrative gap) prior to 14 December 2020 (index date, date vaccinations first began at KPSC) to facilitate accurate capture of comorbid conditions.
Exclusion Criteria Test Negative Design Patients who receive only another newly licensed or investigational SARS-CoV-2 vaccine or COVID-19 prophylactic agent other than Pfizer's COVID-19 vaccine prior to hospitalization (or ED, for secondary objective) will be excluded from the study population When estimating VE for BNT162b2 vaccination, patients receiving another newly licensed or investigational SARS-CoV-2 vaccine or COVID-19 prophylactic agent other than Pfizer's COVID-19 vaccine prior to hospitalization or ED will be excluded from the analysis. Patients will also be excluded if the index date is within certain time windows from vaccination date, outlined further in the exposure section below.
Exclusion Criteria for Cohort Design There will be no exclusion criteria for the cohort design, however patients will be censored for receiving any other newly licensed or investigational SARS-CoV-2 vaccine or COVID-19 prophylactic agent other than Pfizer's COVID-19 vaccine
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Kaiser Permanente Southern California | Pasadena | California | United States | 91101 |
Sponsors and Collaborators
- Pfizer
Investigators
- Study Director: Pfizer CT.gov Call Center, Pfizer
Study Documents (Full-Text)
None provided.More Information
Additional Information:
Publications
None provided.- C4591014