NCT05437510

Study of a Single Intramuscular Dose of Nirsevimab in the Prevention of Hospitalizations Due to Respiratory Syncytial Virus (RSV) Infection in Healthy Term and Preterm Infants During the First Year of Life

A Phase IIIb Randomized Open-label Study of Nirsevimab (Versus no Intervention) in Preventing Hospitalizations Due to Respiratory Syncytial Virus in Infants (HARMONIE)

• Status: Completed
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 8,057 (actual)
• Sponsor: Sanofi Pasteur, a Sanofi Company · Industry
• Sex: All
• Age: 0 Days – 12 Months
• Healthy volunteers: Accepted

Summary

The purpose of this study was to determine the efficacy and safety of a single intramuscular (IM) dose of nirsevimab, compared to no intervention, for the prevention of hospitalizations due to lower respiratory tract infection (LRTI) caused by confirmed RSV infection (henceforth referred to as RSV LRTI hospitalizations) in all infants under 12 months of age who were not eligible to receive palivizumab. The visit frequency was 1 in-person dosing/randomization visit, with monthly safety follow-up electronic contacts through the first 6 months post dosing/randomization for all participants. The study also included a 12-month (Day 366) follow-up telephone call. The D366 follow-up telephone call was the final follow-up telephone call for France, Germany and UK non-reconsented participants. The study included an 18-month (D546) and a 24-month (D731, final telephone call) follow-up telephone call for UK reconsented participants.

Detailed description

12 months post-dosing/randomization for France, Germany and UK non-reconsented participants, 24 months post-dosing/randomization for UK reconsented participants. D01 was the day of randomization (both study groups) and immunization (nirsevimab group).

Conditions

• RSV Immunization
• Healthy Volunteer

Interventions

Type	Name	Description
BIOLOGICAL	Nirsevimab	Pharmaceutical Form: Solution for Injection Route of Administration: Intramuscular

Timeline

• Start date: 2022-08-08
• Primary completion: 2024-03-27
• Completion: 2025-04-09
• First posted: 2022-06-29
• Last updated: 2025-10-09
• Results posted: 2025-04-11

Locations

240 sites across 3 countries: France, Germany, United Kingdom

Regulatory

• FDA-regulated drug study