Which flu shot works best for seniors? hong kong study seeks answers

NCT ID NCT03330132

Completed Prevention Sponsor: The University of Hong Kong Source: ClinicalTrials.gov ↗

First seen Jun 27, 2026 · Last updated Jun 27, 2026

Summary

This study tested several types of flu vaccines in over 1,800 adults aged 65-82 in Hong Kong over four years. The goal was to see which vaccine or combination of vaccines provides the strongest and longest-lasting immune protection. Researchers measured antibody levels and immune cell responses to find the best annual vaccination strategy for older adults.

What this could mean

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

Active substance: Influenza vaccines (standard, adjuvanted, high-dose, and recombinant)
What this could lead to: If successful, this could identify a more effective annual flu vaccination strategy for older adults, reducing flu cases and complications.
What could go wrong: This is a completed Phase 4 trial, so results are available but may not apply to other regions or age groups. Different flu strains each year could also affect how well the findings hold up.

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 INFLUENZA, HUMAN 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.

INFLUENZA, HUMAN

Contacts and locations

Show contact details

Locations

The University of Hong Kong

Hong Kong, China

More trials for these conditions

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