Pfizer-BioNTech COVID-19 Vaccine Effectiveness Study - Kaiser Permanente Southern California
Public ClinicalTrials.gov record NCT04848584. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.
Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.
Official title
Pfizer-BioNTech COVID-19 BNT162b2 Vaccine Effectiveness Study - Kaiser Permanente Southern California
Brief summary
Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.
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. VE estimates by various strata and strain type will be conducted.
Study identification
- NCT ID
- NCT04848584
- Recruitment status
- Completed
- Study type
- Observational
- Phase
- Not listed
- Enrollment
- 1 participant
Conditions and interventions
Conditions
Interventions
- Primary Exposure Status of Pfizer-BioNTech COVID-19 Vaccine Biological
- BNT162b2 BA.4/5 bivalent Biological
- XBB.1.5-adapted vaccinated Biological
Biological
Eligibility (public fields only)
- Age range
- 0 Years and older
- Sex
- All
- Healthy volunteers
- Healthy volunteers not accepted
This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.
Study timeline
- Start date
- May 14, 2021
- Primary completion
- Apr 29, 2025
- Completion
- Apr 29, 2025
- Last update posted
- Jul 28, 2025
2021 – 2025
United States locations
- U.S. sites
- 1
- U.S. states
- 1
- U.S. cities
- 1
| Facility | City | State | ZIP | Site status |
|---|---|---|---|---|
| Kaiser Permanente Southern California | Pasadena | California | 91101 | — |
Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.
About this trial record page
- What this page shows
- Public field values for ClinicalTrials.gov record NCT04848584, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
- What this page does not do
- No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
- Where the data comes from
- Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
- Last refresh
- Last update posted Jul 28, 2025 · Synced Sep 1, 2026
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Open the official record
The complete protocol, eligibility criteria, and contact information for NCT04848584 live on ClinicalTrials.gov.