Mixing COVID-19 vaccines: could two different shots be better?
NCT ID NCT05054621
First seen Jun 22, 2026 · Last updated Jun 22, 2026
Summary
This study tested whether getting a different COVID-19 vaccine for the second shot (instead of the same one) is safe and boosts immunity. 100 healthy adults who had already received one dose of the AZD1222 vaccine were randomly assigned to get either the same vaccine or a different one (MVC-COV1901) as their booster. Researchers measured immune responses and side effects over 168 days.
Disclaimer
Read more
Show less
This is a summary of
the original study
.
Summaries may miss details or leave out important information. Before applying or accepting participation, make sure you have read and understood the full study. Curemydisease.com takes no responsibility whatsoever for anything missed, misunderstood, or acted upon as a result of our summary — we know it does not capture everything.
This is a summary of the original study . Summaries may miss details or leave out important information. Before applying or accepting participation, make sure you have read and understood the full study. Curemydisease.com takes no responsibility whatsoever for anything missed, misunderstood, or acted upon as a result of our summary — we know it does not capture everything.
Get updates
Get notified about this study
Sign up to get updates when this study changes or when new studies for COVID-19 are added.
By submitting, you agree to our Terms of use
Contacts and locations
Show contact details
Enter your email to view the contact information for this study.
By submitting, you agree to our Terms of use
Locations
-
ChangGungMH
Taoyuan, Taiwan, 333, Taiwan
What this could mean
Our plain-language read of the trial. This is informational only — not medical advice or a prediction.
Active substance
COVID-19 vaccines (AZD1222 and MVC-COV1901)
What this could lead to
If mixing vaccines works well, it could offer more flexible and possibly stronger protection against COVID-19.
What could go wrong
This is a small, early-phase study with only 100 participants, so results may not apply to everyone. The long-term safety and effectiveness are still unknown.
Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.