New mRNA vaccine shows promise against common virus that can harm newborns

NCT ID NCT04232280

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

Summary

This study tested an experimental mRNA vaccine called mRNA-1647 to see if it is safe and triggers an immune response against cytomegalovirus (CMV). The trial involved 315 healthy adults aged 18 to 40, some of whom had never been exposed to CMV. Researchers measured side effects and antibody levels after vaccination. The goal is to develop a vaccine that could prevent CMV infection, which can cause serious problems in newborns and people with weak immune systems.

What this could mean

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

Active substance

mRNA-1647 vaccine

What this could lead to

If successful, this vaccine could help prevent cytomegalovirus infection, which is a leading cause of birth defects and complications in people with weakened immune systems.

What could go wrong

This is an early phase 2 trial with only 315 participants, so the vaccine may not work as well in larger, more diverse populations. Side effects like injection site pain, headache, and fatigue were common.

Disclaimer Read more

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 CYTOMEGALOVIRUS INFECTION are added.

Our safety recommendation!

By submitting, you agree to our Terms of use

Conditions

The condition(s) this trial relates to.

DNA Virus Infections viral infectious disease cytomegalovirus infection prevention target

As listed by the trial registrant

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

Contacts and locations

Locations

  • Alliance for Multispecialty Research

    Lexington, Kentucky, 40509, United States

  • Aventiv Research Inc

    Columbus, Ohio, 43213-6523, United States

  • Benchmark Research

    Sacramento, California, 95864, United States

  • Crossroads Clinical Research

    Victoria, Texas, 77901, United States

  • Foothill Family Clinic

    Salt Lake City, Utah, 84109, United States

  • Foothill Family Clinic-South Clinic

    Salt Lake City, Utah, 84121, United States

  • Johnson County Clin-Trials

    Lenexa, Kansas, 66219, United States

  • Optimal Research

    Peoria, Illinois, 61614, United States

  • Tekton Research Inc

    Austin, Texas, 78745, United States