Use and Effectiveness of COVID-19 Vaccines Using State Vaccine Registries and Insurance Claims Data

This study aims to use vaccination information from state vaccine registries linked with HealthVerity insurance claims for the following:

• 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.

Study Overview

• Status: Active, not recruiting
• Conditions: COVID-19; SARS-CoV-2; Post-Acute COVID-19 Syndrome
• Intervention / Treatment: Biological: Pfizer-BioNTech COVID-19 mRNA vaccine

Detailed Description

The vaccine effectiveness (VE) of BNT162b2 COVID-19 vaccine (e.g. KP.2 monovalent formulation) in preventing post-COVID health conditions will be assessed (Aim 1). This aim will utilize a retrospective cohort time-to-event design and evaluate the VE among vaccine-eligible patients from when the vaccine was authorized or approved (specified by age group) through the most current data available. Patients will be sourced from HealthVerity and includes patients who are enrolled in the claims database; data from the state's deidentified vaccine registry will be used to supplement claims data. Patients who will be followed for the PCC endpoint must be eligible to receive the vaccine during the study period. Comparisons between the vaccinated and vaccine eligible but unvaccinated (i.e., no receipt of the most recent formulation) groups will be made using descriptive statistics, incidence rates, and hazard ratios.

The second part of the study (Aim 2) will use a retrospective cohort design to describe 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).

• Study Type: Observational
• Enrollment (Actual): 1

Contacts and Locations

Study Locations

• United States
  • New York
    • New York, New York, United States, 10001
      • Pfizer

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Patients will be sourced from HealthVerity and include patients who are enrolled in the claims database as well as recorded in contributing states' deidentified vaccine registries. Patients who will be followed for the PCC endpoint must be eligible to receive the licensed/authorized vaccine during the study period.

Description

Aim 1:

Inclusion Criteria:

Patients must meet all of the following criteria to be eligible for inclusion in the study:

1. Patients are required to have a COVID-19 diagnosis on or after September 5, 2024 AND no later than August 26, 2025
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

Exclusion Criteria:

Patients meeting any of the following criteria will not be included in the study:

1. Patients who were immunocompromised from 1 year prior to cohort entry OR
2. Patients who received any 2024-2025 formulation of the COVID-19 vaccine prior to authorization (22 August 2024) 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 2024/2025 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)

Patients must meet all of the following inclusion criteria to be eligible for inclusion in the study:

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)

Patients must meet all of the following inclusion criteria to be eligible for inclusion in the study:

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)

Patients must meet all of the following inclusion criteria to be eligible for inclusion in the study:

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

Patients must meet all of the following inclusion criteria to be eligible for inclusion in the study:

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

Patients must meet all of the following inclusion criteria to be eligible for inclusion in the study:

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

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
KP.2 Vaccinated (exposed); ≥14 days since receipt of Pfizer/BioNTech KP.2 dose prior to COVID-19 diagnosis	Biological: 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 Names: Pfizer-BioNTech COVID-19 Vaccine
2024/2025 COVID-19 Unvaccinated (unexposed); Did NOT receive any 2024/2025 formulated COVID-19 vaccine dose at least 14 days prior to COVID-19 diagnosis.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Aim 1: Any PCC-related diagnosis not present before the COVID-19 diagnosis	The primary endpoint is any PCC-related diagnosis as defined by Xie et al. (2024, NEJM) that occurs between 30 and 180 days following a COVID-19 diagnosis and was not present before the COVID-19 diagnosis. The primary endpoint will also be stratified by specific organ system / disease domains (cardiovascular; coagulation and hematologic; fatigue; gastrointestinal; kidney; mental health; metabolic; musculoskeletal; neurologic; and, pulmonary). All patients are required to have a diagnosis of COVID-19 (ICD-10-CM code = U07.1) as a predicating event for the subsequent evaluation of a PCC episode. The first 30 days after the diagnosis of COVID-19 will be excluded from the evaluation of a PCC episode as the acute infection period. The evaluation of the PCC episode will begin on Day 30 after the date of acute COVID-19 diagnosis through day 180.	30-180 days after COVID-19 diagnosis
Aim 2: Number of patients with a COVID-19 vaccination	Any record of COVID-19 vaccination as recorded in the state immunization registry.	Date of vaccine authorization through the end of the corresponding respiratory season

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of patients with cardiovascular-specific Post-COVID condition (PCC) up to 120 days after infection	Secondary endpoints will evaluate PCC by specific organ classes as defined by Xie et al. (doi:10.1001/jamainternmed.2023.0743). All patients are required to have a diagnosis of COVID-19 (ICD-10-CM code = U07.1) as an index event for the subsequent evaluation of a cardiovascular-specific (i.e., dysrhythmia and/or ischemic heart disease) PCC episode. The first 30 days after the diagnosis of COVID-19 will be excluded from the evaluation of a PCC episode as the acute infection period. The evaluation of the cardiovascular-specific PCC episode will begin on Day 31 after the date of COVID-19 diagnosis through day 120.	30-120 days after COVID-19 diagnosis
Number of patients with pulmonary-specific Post-COVID condition (PCC) up to 120 days after infection	Secondary endpoints will evaluate PCC by specific organ classes as defined by Xie et al. (doi:10.1001/jamainternmed.2023.0743). All patients are required to have a diagnosis of COVID-19 (ICD-10-CM code = U07.1) as an index event for the subsequent evaluation of a pulmonary-specific (i.e., shortness of breath and/or cough) PCC episode. The first 30 days after the diagnosis of COVID-19 will be excluded from the evaluation of a PCC episode as the acute infection period. The evaluation of the pulmonary-specific PCC episode will begin on Day 31 after the date of COVID-19 diagnosis through day 120.	30-120 days after COVID-19 diagnosis

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of patients with Post-COVID condition (PCC) up to 180 days after infection	A sensitivity analysis will be conducted to extend follow-up to day 180 post diagnosis date for cardiopulmonary composite PCC diagnosis as defined by Xie et al. (doi:10.1001/jamainternmed.2023.0743). All patients are required to have a diagnosis of COVID-19 (ICD-10-CM code = U07.1) as an index event for the subsequent evaluation of a PCC episode. The first 30 days after the diagnosis of COVID-19 will be excluded from the evaluation of a PCC episode as the acute infection period. The evaluation of the PCC episode will begin on Day 31 after the date of COVID-19 diagnosis through day 180.	30-180 days after COVID-19 diagnosis

Collaborators and Investigators

• Sponsor: Pfizer
• Investigators: Study Director: Pfizer CT.gov Call Center, Pfizer

Publications and helpful links

Helpful Links

• To obtain contact information for a study center near you, click here.

Study record dates

Study Major Dates

• Study Start (Actual): October 23, 2023
• Primary Completion (Estimated): May 31, 2026
• Study Completion (Estimated): September 30, 2026

Study Registration Dates

• First Submitted: May 23, 2023
• First Submitted That Met QC Criteria: May 23, 2023
• First Posted (Actual): May 25, 2023

Study Record Updates

• Last Update Posted (Actual): March 13, 2026
• Last Update Submitted That Met QC Criteria: March 11, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: COVID-19 Vaccines; COVID-19 Drug Treatment
• Additional Relevant MeSH Terms: Post-Infectious Disorders; Pathologic Processes; Chronic Disease; Disease Attributes; Respiratory Tract Infections; Infections; RNA Virus Infections; Virus Diseases; Respiratory Tract Diseases; Lung Diseases; Pneumonia, Viral; Pneumonia; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; Pathological Conditions, Signs and Symptoms; COVID-19; Post-Acute COVID-19 Syndrome; Amino Acids, Peptides, and Proteins; Proteins; Biological Factors; Biological Products; Complex Mixtures; Vaccines; Viral Vaccines; mRNA Vaccines; Nucleic Acid-Based Vaccines; Vaccines, Synthetic; Recombinant Proteins; COVID-19 Vaccines; Antigens; BNT162 Vaccine
• Other Study ID Numbers: C4591059; NCT05876377 (Registry Identifier: ClinicalTrials.gov)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical_trials/trial_data_and_results/data_requests.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No