Use and Effectiveness of COVID-19 Vaccines Using State Vaccine Registries and Insurance Claims Data
NCT ID: NCT05876377
Last Updated: 2025-11-06
Study Results
The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.
Basic Information
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COMPLETED
1 participants
OBSERVATIONAL
2023-10-23
2025-09-09
Brief Summary
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* to measure how effective the Pfizer-BioNTech vaccine is at preventing post-COVID conditions.
* to understand characteristics of patients who are receiving COVID-19 vaccines.
All patients whose information is kept unidentified in the HealthVerity database are eligible to be included for both aims of this study.
Detailed Description
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The second part of the study (Aim 2) will use a retrospective cohort design to examine the uptake of the vaccine in specific groups over time. Subjects will be identified through three different methods: 1) by analyzing all available dosing records in the Immunization Registry, 2) by using HealthVerity claims data based on specific calendar time periods when the vaccine was available, or 3) based on the start of pregnancy that occurs after EUA date. Patients will be followed until experiencing the vaccination under study, disenrollment, end of data or death. Vaccinations will be assessed overall and also by specific type of prior dose (mRNA vs other).
Conditions
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Keywords
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Study Design
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COHORT
RETROSPECTIVE
Study Groups
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XBB Vaccinated (exposed)
≥14 days since receipt of Pfizer/BioNTech XBB dose prior to COVID-19 diagnosis
Pfizer-BioNTech COVID-19 mRNA vaccine
Pfizer-BioNTech COVID-19 Vaccine, is FDA licensed or authorized under Emergency Use Authorization (EUA) for active immunization to prevent coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in individuals 6 months of age and older.
XBB Unvaccinated (unexposed)
Did NOT receive any XBB dose prior to COVID-19 diagnosis
No interventions assigned to this group
Interventions
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Pfizer-BioNTech COVID-19 mRNA vaccine
Pfizer-BioNTech COVID-19 Vaccine, is FDA licensed or authorized under Emergency Use Authorization (EUA) for active immunization to prevent coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in individuals 6 months of age and older.
Other Intervention Names
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Eligibility Criteria
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Inclusion Criteria
1. Patients are required to have a COVID-19 diagnosis on or after September 25, 2023 AND
2. Patients in HealthVerity database and residing in California or Louisiana as of index date AND
3. Have ≥1 year of pharmacy and medical enrollment in HealthVerity prior to cohort entry date, allowing for up to a 30-day gap in enrollment AND
4. ≥18 years old as of index date AND
5. Have resided only in their respective state (California or Louisiana) for ≥1 year prior to index date
1. Has medical and pharmacy enrollment in HealthVerity as of August 31, 2022
2. And is age ≥12 years
3. With 6 months of continuous medical and pharmacy enrollment before calendar index date
4. And does not have evidence of moderate/severe immunocompromise as defined by CDC
5. And has evidence of ≥2 doses of COVID-19 original vaccine formulation before the calendar index date
6. And does not have original vaccine formulation within 2 months before calendar index date
7. And does not have a pregnancy start date within 9 months before or any point after calendar entry
8. And does not have discrepancies in sex and/or year of birth between HealthVerity claims and state Immunization registry datasets.
This analysis will be stratified by age: 12-17, 18-49. 50-64, 65-74, 75+, which will be measured as of August 31, 2022.
By Age, Bivalent (younger children)
1. Has medical and pharmacy enrollment in HealthVerity as of 12 October 2022
2. And is age 5-11 years
3. With 6 months of continuous medical and pharmacy enrollment before calendar index date
4. And does not have evidence of moderate/severe immunocompromise as defined by CDC
5. And has evidence of ≥2 doses of COVID-19 original vaccine formulation before the calendar index date
6. And does not have original vaccine formulation within 2 months before calendar index date.
By Age, Bivalent (youngest children)
1. Has medical and pharmacy enrollment in HealthVerity as of 08 December 2022
2. And is age 6 months-4 years
3. With 6 months of continuous medical and pharmacy enrollment before calendar index date
4. And does not have evidence of moderate/severe immunocompromise as defined by CDC
5. And has evidence of ≥2 doses of COVID-19 original vaccine formulation before the calendar index date
6. And does not have original vaccine formulation within 2 months before calendar index date.
By Disease Status, Bivalent
1. Has medical and pharmacy enrollment in HealthVerity as of 31 August 2022
2. And is age \>=6 months
3. And has continuous medical and pharmacy enrollment for 6 months before the calendar index date
4. And has evidence of 1) moderate/severe immunocompromising condition or separately 2) COVID high-risk condition in a period before the calendar index period (lookback times are dependent on the disease and are provided in variable table below)
5. And has evidence of ≥3 doses of COVID-19 original vaccine formulation before the calendar index date.
For Pregnant Women, Bivalent
1. Has at least 6 months of medical and pharmacy enrollment in HealthVerity as of 31 August 2022
2. And is female sex
3. Aged 12-49
4. And has estimated date of pregnancy start date within 9 months before or any point after the calendar entry date (determined using gestational age algorithm)
5. And has evidence of ≥2 doses of COVID-19 original vaccine formulation before the pregnancy start date or 31 August 2022, whichever is latest.
6. And did not receive the bivalent dose prior to pregnancy, if estimated pregnancy start date is after 31 August 2022
Exclusion Criteria
1. Patients who were immunocompromised from 1 year prior to cohort entry OR
2. Patients who received any 2023-2024 XBB-adapted formulation of the COVID-19 vaccine prior to authorization (11 September 2023) OR
3. Patients who have discrepancies in sex and/or year of birth between HealthVerity claims and state immunization registry datasets OR
4. Patients who had a prior diagnosis of COVID-19 ≤180 days preceding cohort entry OR
5. Patients who received any 2023-2024 XBB-adapted formulation of the COVID-19 vaccine within 0 to 13 days prior OR 0 to 29 days post index COVID-19 diagnosis (i.e., -13 to +29 days around the index date)
Aim 2:
By Age, Bivalent (older children, adults)
6 Months
ALL
No
Sponsors
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Pfizer
INDUSTRY
Responsible Party
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Principal Investigators
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Pfizer CT.gov Call Center
Role: STUDY_DIRECTOR
Pfizer
Locations
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Pfizer
New York, New York, United States
Countries
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Related Links
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To obtain contact information for a study center near you, click here.
Other Identifiers
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NCT05876377
Identifier Type: REGISTRY
Identifier Source: secondary_id
C4591059
Identifier Type: -
Identifier Source: org_study_id