Dose-Finding Trial to Evaluate the Safety and Immunogenicity of Cytomegalovirus Vaccine mRNA-1647 in Healthy Adults

Study Purpose

This clinical study will assess the safety and immunogenicity of 3 dose levels of mRNA-1647 cytomegalovirus vaccine in CMV-seronegative and CMV-seropositive healthy adults 18-40 years of age.

Recruitment Criteria

Accepts Healthy Volunteers

Healthy volunteers are participants who do not have a disease or condition, or related conditions or symptoms

Study Type

An interventional clinical study is where participants are assigned to receive one or more interventions (or no intervention) so that researchers can evaluate the effects of the interventions on biomedical or health-related outcomes.

An observational clinical study is where participants identified as belonging to study groups are assessed for biomedical or health outcomes.

Searching Both is inclusive of interventional and observational studies.

Eligible Ages 18 Years - 40 Years
Gender All
More Inclusion & Exclusion Criteria

Inclusion Criteria:

  • - Male or female 18-40 years of age (Part 1); Female 18-40 years of age (Part 2) - Understands and agrees to comply with the trial procedures and provides written informed consent.
  • - According to the assessment of the Investigator, is in good general health and is capable of complying with trial procedures.
  • - Body mass index (BMI) 18-35 kg/m^2.
  • - Female subjects must either be of non-childbearing potential or use acceptable methods of contraception from at least 30 days prior to enrollment and through 3 months following last vaccination.
  • - Male subjects must agree to practice adequate contraception for 30 days prior to the first vaccination and through 3 months following the last vaccination.

Exclusion Criteria:

  • - Acutely ill or febrile on the day of the first vaccination.
  • - Prior receipt of any CMV vaccine.
  • - Abnormal screening safety laboratory test results.
  • - Diagnosis or condition that, in the judgment of Investigator, is clinically unstable or may affect participant safety, assessment of safety endpoints, assessment of immune response, or adherence to trial procedures.
  • - Has received or plans to receive a vaccine ≤ 28 days prior to the first vaccination or plans to receive a non-study vaccine within 28 days prior to or after any study vaccination, except for any licensed influenza vaccine which can be administered > 14 days before or after any study vaccination.
  • - Prior receipt of chronic systemic immunosuppressants or immune-modifying drugs.
  • - Receipt of intravenous immunoglobulins or plasma products within 3 months prior to the day of the first study vaccination.
  • - Previous receipt of medications in lipid nanoparticle (LNP) formulation.
  • - Has donated ≥ 450 mL of blood products within 28 days of the Screening visit.
  • - Participated in an interventional clinical trial within 28 days prior to the day of enrollment.
- Is an immediate family member or household member of trial personnel

Trial Details

Trial ID:

This trial id was obtained from, a service of the U.S. National Institutes of Health, providing information on publicly and privately supported clinical studies of human participants with locations in all 50 States and in 196 countries.


Phase 1: Studies that emphasize safety and how the drug is metabolized and excreted in humans.

Phase 2: Studies that gather preliminary data on effectiveness (whether the drug works in people who have a certain disease or condition) and additional safety data.

Phase 3: Studies that gather more information about safety and effectiveness by studying different populations and different dosages and by using the drug in combination with other drugs.

Phase 4: Studies occurring after FDA has approved a drug for marketing, efficacy, or optimal use.

Phase 2
Lead Sponsor

The sponsor is the organization or person who oversees the clinical study and is responsible for analyzing the study data.

ModernaTX, Inc.
Principal Investigator

The person who is responsible for the scientific and technical direction of the entire clinical study.

Principal Investigator Affiliation N/A
Agency Class

Category of organization(s) involved as sponsor (and collaborator) supporting the trial.

Overall Status Recruiting
Countries United States

The disease, disorder, syndrome, illness, or injury that is being studied.

Cytomegalovirus Infection
Arms & Interventions


Experimental: CMV-seronegative

Escalating dose levels

Experimental: CMV-seropositive

Escalating dose levels


Biological: - mRNA-1647

Cytomegalovirus vaccine

Other: - Placebo


Contact a Trial Team

If you are interested in learning more about this trial, find the trial site nearest to your location. We also strongly recommend that you consult with your healthcare provider about the trials that may interest you. Please note all sites listed may not currently be active in the trial. Please continue to check back for additional site locations.

Benchmark Research
Recruiting | Sacramento, California, United States, 95864
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Optimal Research
Recruiting | Peoria, Illinois, United States, 61614
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Johnson County Clin-Trials
Recruiting | Lenexa, Kansas, United States, 66219
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Alliance for Multispecialty Research
Recruiting | Lexington, Kentucky, United States, 40509
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Meridian Clinical Research
Not yet recruiting | Norfolk, Nebraska, United States, 68701
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Lynn Health Science Institute
Not yet recruiting | Oklahoma City, Oklahoma, United States, 73112
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Tekton Research Inc
Recruiting | Austin, Texas, United States, 78745
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Benchmark Research
Not yet recruiting | Fort Worth, Texas, United States, 76135
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Crossroads Clinical Research
Recruiting | Victoria, Texas, United States, 77901
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Tanner Clinic
Not yet recruiting | Layton, Utah, United States, 84041
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Foothill Family Clinic
Recruiting | Salt Lake City, Utah, United States, 84109
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Foothill Family Clinic-South Clinic
Recruiting | Salt Lake City, Utah, United States, 84121
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