Repeated Cross Sectional Surveillance Study To Determine the Respiratory Syncytial Virus (RSV) Immunization Rates in German Infants (Vakzimeter RSV)

Repeated Cross Sectional Surveillance Study To Determine the Respiratory Syncytial Virus (RSV) Immunization Rates in German Infants During Three RSV Seasons

In June 2024, the German Standing Committee on Vaccination (STIKO) recommended the universal immunization of infants with nirsevimab during their first RSV season. Nirsevimab is a long-acting monoclonal antibody designed to provide passive immunity against RSV, significantly reducing the risk of severe RSV disease in infants. This recommendation marks the 2024/25 season as the first in which nirsevimab is broadly implemented for all infants in Germany.

Despite the introduction of this new prevention measure, there is currently no timely monitoring system for immunization rates. Understanding the uptake and coverage of nirsevimab is crucial for evaluating its impact on public health and guiding future vaccination strategies. Therefore, this study aims to monitor the national immunization rates of nirsevimab in children under one year of age during the initial seasons of its widespread use.

The primary objective of this study is to determine the Nirsevimab immunization rate in eligible infants in their first RSV-season in Germany. The study will focus on:

1. Assessing the immunization rates among eligible infants (according to STIKO recommendation) in their first RSV-season in Germany (i.e. across all geographies)
2. Assessing the immunisation rates among the "catch-up cohort", i.e. all infants born between April and September. For these infants, the STIKO recommends immunization with nirsevimab in early autumn.
3. Assessing the immunization rate among the "in-season cohort", i.e. all infants born during the RSV season between October and March. For these newborns, the STIKO recommends immunization with Nirsevimab shortly after birth, preferably during the second "well-baby visit" at the age of 3-10 days of life.

Study Overview

• Status: Active, not recruiting
• Conditions: Respiratory Syncytial Virus Immunization

• Study Type: Observational
• Enrollment (Estimated): 2400

Contacts and Locations

Study Locations

• Germany
  • Germany, Germany

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

This study is conducted using various recruitment approaches, including but not limited to mailings, online panels, telephone contact, in person contact. The data i.e. respondents answers will be captured via an online questionnaire. The interviews will be conducted applying various methodologies e.g. self-completion (CAWI), assisted in person completion (F2F interviews), assisted telephone completion (CATI).

The study will target a sample of parents of infants either born between April and September (catch-up cohort) or between October and March (in-season cohort). The study targets a representative distribution with regards to both aforementioned subgroups and regions.

To achieve the primary objective in the representative sample of the German population of eligible parents, a needed sample size of approximately 2,400 participants in total per season is assessed. These are spread over a total of three waves per season, resulting in a sample size of 800 respondents per wave.

Description

Inclusion Criteria:

• Be a parent of an infant born between April 2024/25/26 and March 2025/26/27, respectively
• Reside in Germany at the time of survey completion
• Be at least 18 years old at the time of survey completion.
• Agree with privacy policy and AE (Adverse Event) reporting requirements before proceeding with the survey.
• Read and agree to the ICF (Informed Consent Form) by ticking a box before proceeding with the survey.

Exclusion Criteria:

• Participation in the study (= completed the survey) in a previous wave of the current season.

Note: The above information is not intended to contain all considerations relevant to a potential participation in a clinical trial.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Catch-Up Cohort; Parents of infants born between April and September
In-Season Cohort; Parents of infants born between October and March

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Assessing the nirsevimab immunization rates among eligible infants in both cohorts	Descriptive analysis of nirsevimab immunization status (yes/no) will be performed using summary statistics, i.e., proportion of immunized infants among all enrolled infants per wave.	Throughout Study (Approximatley 4 months)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Assessing the seasonal evolution of the nirsevimab immunization coverage rates among the two cohorts	Descriptive analysis of nirsevimab immunization status over time will be performed using summary statistics, i.e., proportion of immunized infants among all enrolled infants per wave.	Throughout Study (Approximatley 4 months)
Assessing reasons for/against nirsevimab immunization	The analysis for any potential influencing factors will be based on descriptive analytics and complemented with bi-variate analytics where applicable	Throughout Study (Approximately 4 months)
Assessing the nirsevimab immunization rates among subgroups	A descriptive analysis of immunization rates will be performed on subgroups such as: risk group (defined chronic condition or pre-term birth status), federal states and health insurance/Kassenärztliche Vereinigung, physician's association regions	Throughout Study (Approximately 4 months)
Assessing the reliability of a demographic study	Assessing reliability based on randomly sampled parent population using Computer-Assisted Web Interview (CAWI)/ Computer-Assisted Telephone Interview (CATI)/ face-to-face interviews for estimating immunization rates in Germany	Throughout the Study (Approximately 4 months)

Collaborators and Investigators

• Sponsor: Sanofi Pasteur, a Sanofi Company

Study record dates

Study Major Dates

• Study Start (Actual): January 13, 2025
• Primary Completion (Estimated): May 30, 2026
• Study Completion (Estimated): May 30, 2026

Study Registration Dates

• First Submitted: February 7, 2025
• First Submitted That Met QC Criteria: February 7, 2025
• First Posted (Actual): February 13, 2025

Study Record Updates

• Last Update Posted (Estimated): June 5, 2025
• Last Update Submitted That Met QC Criteria: June 4, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Keywords: RSV; Nirsevimab; RSV Immunization Rates
• Additional Relevant MeSH Terms: Infections; Virus Diseases
• Other Study ID Numbers: RSV00093

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants. Further details on Sanofi's data sharing criteria, eligible studies, and process for requesting access can be found at: https://vivli.org

Drug and device information, study documents

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