# 406. Effectiveness of the JN.1-adapted BNT162b2 COVID-19 Vaccine in High-Risk Groups against Hospitalization in Europe: A Test-Negative Case-Control using the id.DRIVE Platform

## TL;DR

This study shows the JN.1-adapted BNT162b2 vaccine is effective at preventing hospitalization from COVID-19 in high-risk groups across Europe.

## Contribution

The study provides new evidence on the real-world effectiveness of the JN.1-adapted BNT162b2 vaccine in high-risk populations.

## Key findings

- The vaccine was 76.5% effective against hospitalization, with protection lasting up to six months.
- Effectiveness was similar across age groups, including adults over 80 years old.
- The vaccine showed strong protection in patients with chronic conditions like lung disease and diabetes.

## Abstract

There is limited information on COVID-19 vaccine effectiveness (VE) among specific groups at high risk for severe COVID-19, including older adults and patients with chronic conditions. We report on the VE of the JN.1-adapted BNT162b2 vaccine in various high-risk groups.Table 1.Characteristics of study patients hospitalized with severe acute respiratory infection according to JN.1-adapted BNT162b2 vaccine receipt and SARS-CoV-2 status, in Europe, September 2024–May 2025*Does not include vaccination regimens with vaccines not mentioned here (n=49)** Study sites included 1 hospital located in Germany and 10 hospitals located in Spain.Figure 1.Flow diagram of the study population in id.DRIVE, September 2024–May 2025SARI: severe acute respiratory infection

Characteristics of study patients hospitalized with severe acute respiratory infection according to JN.1-adapted BNT162b2 vaccine receipt and SARS-CoV-2 status, in Europe, September 2024–May 2025

*Does not include vaccination regimens with vaccines not mentioned here (n=49)

** Study sites included 1 hospital located in Germany and 10 hospitals located in Spain.

Flow diagram of the study population in id.DRIVE, September 2024–May 2025

SARI: severe acute respiratory infection

We conducted a test-negative case-control study in the id.DRIVE platform (EUPAS42328) of adults ≥18 years hospitalized with a severe acute respiratory infection in sites across Germany and Spain from 3 September 2024–31 May 2025. Vaccination status was determined using registries or medical documentation. Exposed patients received ≥1 dose of the JN.1-adapted BNT162b2 vaccine, while unexposed patients did not receive any COVID-19 vaccine in the 2024–2025 season. SARS-CoV-2 status was confirmed by PCR. Multivariable analyses were adjusted for symptom onset date, age, sex, number of chronic conditions, and influenza vaccination status. Cases were matched with up to 4 controls by site and symptom onset date (two-week interval). Adjusted VE was calculated as (1− odds ratio) × 100%.Figure 2.Vaccine effectiveness against COVID-19 hospitalization in patients with a severe acute respiratory infection who received at least one dose of JN.1-adapted BNT162b2 vaccine compared with patients who did not receive any dose of a COVID-19 vaccine in the 2024–2025 seasonCI confidence interval; N: number; Q1/Q3: quartile 1/3; VE: Vaccine effectiveness; wks: weeks; y: years.¹Vaccine effectiveness estimates are adjusted for date of symptom onset, age, sex, number of chronic conditions, and receipt of influenza vaccine in the 12 months prior to current hospital admission.²’Never vaccinated’ study participants were excluded when calculating the median (IQR) of time since last vaccine dose in the unexposed group (patients who did not receive any dose of a COVID-19 vaccine in the 2024–2025 season)³The categories ‘Cancer’ and ‘Immunodeficiency’ among chronic conditions are counted as separate types of chronic conditions in all adjusted VE estimates. Here, the VE estimate among participants having ‘Immunodeficiency or cancer’ is provided as a composite.

Vaccine effectiveness against COVID-19 hospitalization in patients with a severe acute respiratory infection who received at least one dose of JN.1-adapted BNT162b2 vaccine compared with patients who did not receive any dose of a COVID-19 vaccine in the 2024–2025 season

CI confidence interval; N: number; Q1/Q3: quartile 1/3; VE: Vaccine effectiveness; wks: weeks; y: years.

¹Vaccine effectiveness estimates are adjusted for date of symptom onset, age, sex, number of chronic conditions, and receipt of influenza vaccine in the 12 months prior to current hospital admission.

²’Never vaccinated’ study participants were excluded when calculating the median (IQR) of time since last vaccine dose in the unexposed group (patients who did not receive any dose of a COVID-19 vaccine in the 2024–2025 season)

³The categories ‘Cancer’ and ‘Immunodeficiency’ among chronic conditions are counted as separate types of chronic conditions in all adjusted VE estimates. Here, the VE estimate among participants having ‘Immunodeficiency or cancer’ is provided as a composite.

A total of 764 patients were included in the analysis, including 161 cases and 603 controls, of whom 309 (40.4%) received a JN.1-adapted BNT162b2 vaccine. Overall, VE against hospitalization was 76.5% (95% CI: 57.9; 86.9) at a median 92 days (IQR 66; 157) since vaccination with sustained protection through 24–32 weeks since dose. VE was similar across age groups; VE was 81.0% (95% CI: 56.5; 91.7) among adults 65–79 years and 78.3% (95% CI: 46.0; 91.3) among adults ≥80 years. BNT162b2 was effective among adults with specific chronic conditions, including lung disease, cardiovascular disease, hypertension, type 2 diabetes, and obesity, while estimates lacked precision for asthma, chronic liver disease, renal disease, type 1 diabetes, and neurological disorder. VE was 67.4% (95% CI: 9.3; 88.3) among patients with immunodeficiency or cancer.

The JN.1-adapted BNT162b2 vaccine was effective against hospitalization during the 2024–2025 season in a range of high-risk groups and provided durable protection lasting through 6 months. These findings support the clinical benefit of BNT162b2 among groups at high-risk for severe disease and emphasize the continued importance of COVID-19 vaccination in high-risk patients.

All Authors: No reported disclosures