New mRNA flu shot enters first human tests

NCT ID NCT05426174

Completed ⭐️ VACCINE ⭐️ Sponsor: Sanofi Pasteur, a Sanofi Company Source: ClinicalTrials.gov ↗

First seen Jun 26, 2026 · Last updated Jun 26, 2026

Summary

This early-stage trial tested a new mRNA-based flu vaccine in 233 healthy adults aged 18 and older. The study compared three different doses of the experimental vaccine to a standard high-dose flu shot. Researchers monitored safety and immune responses over time to see if the new vaccine could be a promising option for flu prevention.

What this could mean

Our plain-language read of the trial. This is informational only — not medical advice or a prediction.

Active substance: mRNA NA vaccine
What this could lead to: If successful, this could lead to a new type of flu vaccine that may offer better protection against influenza.
What could go wrong: This is an early Phase 1 trial with only 233 participants, so safety and effectiveness are not yet proven. The vaccine may not work as hoped or could cause side effects.

This is an AI summary of the original study and may miss details. Read our disclaimer.

Get updates

Get notified about this study

Sign up to get updates when this study changes or when new studies for HEALTHY VOLUNTEERS are added.

Our safety recommendation!

By submitting, you agree to our Terms of use

Conditions

The condition(s) this trial relates to.

influenza prevention target

As listed by the trial registrant

The condition terms exactly as the trial's registrant entered them.

HEALTHY VOLUNTEERS INFLUENZA IMMUNIZATION

Contacts and locations

Locations

AES - DRS - Optimal Research_Site 8400001

Peoria, Illinois, 61614-4885, United States
AES - DRS - Optimal Research_Site 8400002

Melbourne, Florida, 32934-8172, United States
AES - DRS - Optimal Research_Site 8400007

Huntsville, Alabama, 35802, United States
Central Phoenix Medical Clinic, LLC_Site: 8400010

Phoenix, Arizona, 85020, United States
Optimal Research San Diego, LLC_Site: 8400009

San Diego, California, 92108, United States
Synexus Clinical Research_Site 8400003

Cincinnati, Ohio, 45236, United States

More trials for these conditions

Other studies related to the condition(s) this trial covers.