A Study of an Epstein-Barr Virus (EBV) Candidate Vaccine, mRNA-1189, in 12- to 30-Year-Old Healthy Adolescents and Adults

Study Overview
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Brief Summary
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The main objective of Part A of this trial is to evaluate the safety and reactogenicity of mRNA-1189 in 18- to 30-year-old healthy adults and the main objective of Part B is to evaluate the safety and reactogenicity of mRNA-1189 in 12- to <18-year-old EBV-seronegative healthy adolescents.

Official Title
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A Phase 1, Randomized, Observer-Blind, Placebo-Controlled, Dose-Ranging Study of an Epstein-Barr Virus (EBV) Candidate Vaccine, mRNA-1189, in 12- to 30-Year-Old Healthy Adolescents and Adults

Conditions
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Epstein-Barr Virus Infection

Intervention / Treatment
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* Biological: mRNA-1189
* Biological: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: According to the assessment of the investigator, is in good general health and can comply with study procedures. Part A: Healthy adult from 18 to 30 years of age (inclusive) at the time of consent (Screening Visit, Day 0). Part B: Healthy adolescent from 12 to <18 years of age at the time of consent (Screening Visit, Day 0). EBV - seronegative as determined by serology at screening. Exclusion Criteria: Has had significant exposure to someone with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection or COVID-19 in the past 14 days prior to the screening visit, if the participant has not been fully vaccinated against COVID-19 at least 14 days prior to the screening visit. Has symptomatic acute or chronic illness requiring ongoing medical or surgical care, to include changes in medication in the past 2 months indicating that chronic illness/disease is not stable (at the discretion of the investigator). Significant, progressive, unstable or uncontrolled clinical condition, including any condition that may affect participant safety, assessment of study endpoints, assessment of immune response, or adherence to study procedures per investigator judgement. Has a history of myocarditis, and/or pericarditis. Has received or plans to receive any licensed or authorized vaccine, to include COVID-19 vaccines, ≤28 days prior to the first injection (Day 1) or plans to receive a licensed vaccine within 28 days before or after any study vaccine injection, with the exception of licensed influenza vaccines, which may be received more than 14 days before or after any study vaccine injection. Note: Other inclusion and exclusion criteria may apply.

Ages Eligible for Study
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Minimum Age: 12 Years
Maximum Age: 30 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Part A: mRNA-1189 Dose Level 2<br>Participants will receive 3 intramuscular (IM) injections of mRNA-1189 at Dose Level 2 on Days 1, 57, and 169. | Biological: mRNA-1189<br>* Sterile liquid for injection<br>|
| Experimental: Part A: mRNA-1189 Dose Level 3<br>Participants will receive 3 IM injections of mRNA-1189 at Dose Level 3 on Days 1, 57, and 169. | Biological: mRNA-1189<br>* Sterile liquid for injection<br>|
| Experimental: Part A: mRNA-1189 Dose Level 4<br>Participants will receive 3 IM injections of mRNA-1189 at Dose Level 4 on Days 1, 57, and 169. | Biological: mRNA-1189<br>* Sterile liquid for injection<br>|
| Placebo Comparator: Part A: Placebo<br>Participants will receive 3 IM injection of study drug-matching placebo on Days 1, 57, and 169. | Biological: Placebo<br>* 0.9% sodium chloride (normal saline) injection<br>|
| Experimental: Part B: mRNA-1189 Dose Level 1<br>Participants will receive 3 IM injections of mRNA-1189 at Dose Level 1 on Days 1, 57, and 169. | Biological: mRNA-1189<br>* Sterile liquid for injection<br>|
| Experimental: Part B: mRNA-1189 Dose Level 2<br>Participants will receive 3 IM injections of mRNA-1189 at Dose Level 2 on Days 1, 57, and 169. | Biological: mRNA-1189<br>* Sterile liquid for injection<br>|
| Experimental: Part B: mRNA-1189 Dose Level 3<br>Participants will receive 3 IM injections of mRNA-1189 at Dose Level 3 on Days 1, 57, and 169. | Biological: mRNA-1189<br>* Sterile liquid for injection<br>|
| Experimental: Part B: mRNA-1189 Dose Level 4<br>Participants will receive 3 IM injections of mRNA-1189 at Dose Level 4 on Days 1, 57, and 169. | Biological: mRNA-1189<br>* Sterile liquid for injection<br>|
| Placebo Comparator: Part B: Placebo<br>Participants will receive 3 IM injection of study drug-matching placebo on Days 1, 57, and 169. | Biological: Placebo<br>* 0.9% sodium chloride (normal saline) injection<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants with Solicited Local and Systemic Reactogenicity Adverse Reactions (ARs) |  | Up to Day 176 (7-day follow-up after vaccination) | 
| Number of Participants with Unsolicited Adverse Events (AEs) |  | Up to Day 197 (28-day follow-up after vaccination) | 
| Number of Participants with Any Serious AEs (SAEs), Medically Attended AEs (MAAEs), AEs Leading to Withdrawal From Study/Discontinuation of Study Vaccine, and AEs of Special Interest (AESIs) |  | Day 1 to end of study (EOS) (Day 505) | 
| Number of Participants with Laboratory Abnormalities |  | Up to Day 176 (7-day follow-up after vaccination) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Geometric Mean Titer (GMT) of B-Cell Neutralizing Antibody (nAb) and/or Antigen-Specific Binding Antibody (bAb) |  | Days 1, 85, and 197 | 
| Geometric Mean Fold Rise (GMFR) of B-Cell nAb and Antigen-Specific bAb |  | Days 1, 85, and 197 | 
| Number of Participants With Seroconversion of B-Cell nAbs and/or Antigen-Specific bAbs | The number of initially EBV-negative participants with seroconversion from below the lower limit of quantification (LLOQ) to above the LLOQ for EBV-specific (vaccine antigen) binding and nAbs responses and the initially EBV-positive participants with > 2-, 3-, and 4-fold increases in serum binding or nAb titers from baseline (if above LLOQ) will be analyzed. | Days 1, 85, and 197 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Infectious mononucleosis, Mononucleosis