CI

At a glance

ClinicalIndex Comparison Record
Phase 2Completed· 306 enrolled
Drug / intervention
Quadrivalent Inactivated Influenza High Dose +1 morebiological
Likely dose
Not stated in record
Structured eligibility isn't available for this trial yet — see the full criteria in the Eligibility tab below.

Standardized by ClinicalIndex from the ClinicalTrials.gov record · verify against the source.

Search/NCT04969276
NCT04969276Phase 2Completed

A Phase II, Open-label Study to Assess the Safety and Immunogenicity of Fluzone® High-Dose Quadrivalent (Influenza Vaccine), 2021-2022 Formulation and a Third Dose of Moderna COVID-19 Vaccine (mRNA-1273 Vaccine) Administered Either Concomitantly or Singly in Adults 65 Years of Age and Older Previously Vaccinated With a 2-dose Schedule of Moderna COVID-19 Vaccine

Sanofi Pasteur, a Sanofi Company·interventional·Posted Jul 20, 2021·Updated Sep 12, 2025

In Brief

A Phase 2 clinical trial evaluating Quadrivalent Inactivated Influenza High Dose and COVID-19 mRNA Vaccine (nucleoside modified) for Influenza Immunization and Healthy Volunteers. Completed, enrolled 306 participants across 6 sites.

Detailed Summary

The main purpose of this Phase II study was to assess the safety and immunogenicity of a dose of Fluzone High-Dose (HD) Quadrivalent vaccine and a third dose or booster dose of Moderna coronavirus disease 19 (COVID-19) vaccine administered concomitantly or singly in adults 65 years of age and older having received their second dose of the 2-dose schedule of Moderna COVID-19 vaccine at least 5 months before enrollment in the study.

Study Details

Study Typeinterventional
Allocation--
Masking--
Primary Purpose--
CountriesUnited States
Collaborators--

Timeline

Phase 2CompletedFinished
20222023202420252026
First PostedJul 20, 2021
Enrollment StartJul 16, 2021
Primary CompletionFeb 8, 2022
TodayJul 2, 2026
Enrollment to primary: 7 monthsPosted 5.0 years ago

Interventions

Quadrivalent Inactivated Influenza High Dosebiological

Sterile suspension for injection in a pre-filled syringe Intramuscular injection

COVID-19 mRNA Vaccine (nucleoside modified)biological

Sterile suspension (white to off-white) in multidose vial Intramuscular injection