An observational study in Community-Acquired Pneumonia (CAP), sponsored by Pfizer. Active, not recruiting at 1 site in United States. Open to participants aged 19 Years and older. Per ClinicalTrials.gov, last updated 2026-08-25.
Sponsored by Pfizer · Observational
The purpose of this study is to learn how well PCV20 stops adults from getting community-acquired pneumonia. Pneumonia is an infection of the lungs that can be caused by germs like bacteria, virus, or fungi. This study uses existing healthcare information. No participants will be actively enrolled. The information of participants will be taken from Kaiser Permanente Southern California's (KPSC) electronic health records (EHR).
We will look at the EHR information for adults who meet the following points:
The study will begin on 01 July 2022 and end on 30 June 2025. At the end of the follow-up period, the study will compare the number of community-acquired pneumonia cases among people who did and did not receive PCV20.
82 studies on the registry are indexed under Community-Acquired Pneumonia; 51 are open to participants now.
This study's enrollment of 846,279 is above the median of 650 across 27 observational studies indexed under Community-Acquired Pneumonia.
Browse Community-Acquired Pneumonia studies →Pfizer is the lead sponsor of 3,244 studies on the registry; 139 are open to participants now.
Of its 582 completed or terminated interventional studies of FDA-regulated products, 381 (65%) have results posted.
Counted across the registry records on this site, refreshed daily.
The study will include a cohort of adults 19-64 years of age with at least one medical or behavioral risk factor associated with an increased risk of pneumococcal disease and a cohort of adults ≥65 years of age. Individuals who meet the eligibility criteria as of 01 July 2022 or who become eligible during the cohort identification period (01 July 2022 through 31 May 2025) will be included in the study. Individuals could contribute to both the 19-64 and ≥65 years of age cohorts if the individual met the inclusion and exclusion criteria for each respective cohort. Follow-up time will be classified by PCV20 exposure status. Within each cohort (19-64, ≥65 years), individuals can contribute one PCV20-unvaccinated time-segment, one PCV20-vaccinated time-segment, or both.
19-64 years of age cohort 1. Aged ≥19 at some point between July 1, 2022 and May 31, 2025 with 1-year continuous membership prior to July 1, 2022 2. At least 1 year of continuous enrollment as a KPSC member prior to the index date, allowing for 45-day administrative gaps 3. Age 19-64 years of age on the index date with ≥1 medical condition or risk factor identified during the 1-year continuous enrollment period prior to the index date 4. At least one outpatient visit prior to the index date
65 years cohort
Exclusion Criteria:
19-64 years of age cohort
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65 years cohort
For the 19-64 years of age cohort, the unvaccinated index date is the earliest day during the cohort identification period when the individual is 19-64 years of age, has ≥1 year of prior continuous enrollment, and has a medical or behavioral risk factor during the prior 1-year continuous enrollment period. The vaccinated index is the day during the cohort identification period that is 30 days after PCV20 vaccination received when the individual has ≥1 year of prior continuous enrollment, is 19-64 years of age, and has a risk factor identified during the prior 1-year continuous enrollment period.
Biological: Receipt of PCV20
For the ≥65 years of age cohort, the unvaccinated index date is the earliest day between 01 July 2022 and 31 May 2025 (cohort identification period) when the individual is ≥65 years of age and has ≥1 year of prior continuous enrollment. The vaccinated index date is the date during the cohort identification period that is 30 days after PCV20 vaccination received when the individual is ≥65 years of age and has ≥1 year of prior continuous enrollment.
Biological: Receipt of PCV20
The main exposure of interest will be receipt of PCV20.
PCV20 vaccine effectiveness (VE) against all-cause pneumonia (ACP) separately among both adults 19-64 years of age with medical conditions and behavioral risk factors and among adults ≥65 years of age
PCV20 VE against ACP calculated as (1-aHR) × 100% separately among adults aged 19-64 years with medical conditions or behavioral risk factors and among adults ≥65 years of age
Time frame: 3 years
Incidence rates calculated separately among adults 19-64 years of age with medical conditions or behavioral risk factors and among adults ≥65 years of age
Unweighted and unadjusted incidence rates will be calculated as the number of ACP episodes per 100,000 person-years overall and separately for PCV20-vaccinated and unvaccinated time-segments. Incidence rates will be calculated separately among adults 19-64 years of age with medical conditions or behavioral risk factors and among adults ≥65 years of age
Time frame: 3 years
Absolute rate reduction of ACP associated with PCV20 vaccination calculated separately among adults 19-64 years of age with medical conditions or behavioral risk factors and among adults ≥65 years of age
Absolute rate reduction of ACP associated with PCV20 vaccination will be calculated using the weighted VE estimate from the Cox proportional hazards model along with the non-model based unadjusted incidence rate (IR) during PCV20-vaccinated follow-up time. Absolute rate reduction will be calculated separately among adults 19-64 years of age with medical conditions or behavioral risk factors and among adults ≥65 years of age.
Time frame: 3 years
Plan to share: No
This study is active, not recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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