A Study to Evaluate the Immunogenicity and Safety of mRNA-1283 COVID-19 Variant-containing Formulations

NCT07089706 | Completed Phase 4 DMC FDA Drug

• 1 other identifier: mRNA-1283-P401
• Study Type: interventional
• Target: 832
• Locations: 1 country
• Sites: 5

Brief Summary

The purpose of this study is to evaluate the immunogenicity and safety of the recommended variant-containing formulations of mRNA-1283 COVID-19 vaccine (mNEXSPIKE®) within the current epidemiological environment.

Conditions

COVID-19

Keywords

mRNA-1283; mRNA-1283 vaccine; SARS-CoV-2; SARS-CoV-2 Vaccine; Coronavirus; Coronavirus Infections; Virus Diseases; mNEXSPIKE®; COVID-19; COVID-19 vaccine; Moderna

Outcome Measures

Primary Outcomes (4)

• Subprotocol 1: Part A - Geometric Mean (GM) Value of Neutralizing Antibody (nAb) Against Vaccine-matched COVID-19 Variants

  Day 29

• Subprotocol 1: Part A - Geometric Mean Fold Rise (GMFR) of nAb Against Vaccine-matched COVID-19 Variants

  Baseline to Day 29

• Subprotocol 1: Part B - GMFR of nAb Against Vaccine-matched COVID-19 Variants

  Baseline to Day 29

• Subprotocol 1: Part A - Seroresponse Rate (SRR) of nAb Against Vaccine-matched COVID-19 Variants

  Baseline to Day 29

Secondary Outcomes (5)

• Subprotocol 1: Part A - Number of Participants with Unsolicited Adverse Events (AEs), Serious Adverse Events (SAEs), AEs of Special Interests (AESIs), and AEs Leading to Study Withdrawal

  Day 1 through Day 29

• Subprotocol 1: Part B - Number of Participants with Unsolicited AEs

  Day 1 through Day 29

• Subprotocol 1: Part B - Number of Participants with SAEs, AESIs, and AEs Leading to Study Withdrawal

  Day 1 through Day 181

• Subprotocol 1: Part B - Geometric Mean Ratio (GMR) of nAb Against Vaccine-matched COVID-19 Variants Between Participants Aged ≥12 to <65 Years and Those Aged ≥65 Years

  Day 29

• Subprotocol 1: Part B - Number of Participants With Solicited Local and Systemic Adverse Reactions (ARs)

  7 days post vaccination

Study Arms (1)

mRNA-1283.251 Variant-containing Formulation

EXPERIMENTAL

Participants will receive an intramuscular (IM) injection of a mRNA-1283.251 variant-containing formulation.

Biological: mRNA-1283.251 Variant-containing Formulation

Interventions

mRNA-1283.251 Variant-containing Formulation BIOLOGICAL

Sterile liquid for injection

Also known as: mNEXSPIKE®

mRNA-1283.251 Variant-containing Formulation

Eligibility Criteria

• Age: 12 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• Subprotocol 1:
• ≥65 years of age at the time of signing the informed consent or ≥12 to \<65 years of age at the time of signing the informed consent with at least 1 risk factor for severe outcomes from COVID-19.
• Investigator's assessment that the participant understands and is willing and physically able to comply with protocol-mandated follow-up, including all procedures.
• Participants who are assigned female at birth or could become pregnant:
• i) Has a negative pregnancy test at the Screening Visit and on the day of vaccination prior to vaccine dose being administered on Day 1.
• ii) Has practiced adequate contraception or has abstained from all activities that could result in pregnancy for at least 28 days prior to the first dose (Day 1).
• iii) Has agreed to continue adequate contraception through 28 days following vaccine administration.

You may not qualify if:

• Subprotocol 1:
• History of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection within 6 months prior to enrollment.
• Acutely ill or febrile (temperature ≥38.0°Celsius/≥100.4°Fahrenheit) within 72 hours prior to or at the Screening Visit or Day 1. Participants meeting this criterion may be rescheduled within the Screening window and will retain their initially assigned participant number.
• History of a diagnosis or condition that, in the judgment of the Investigator, is clinically unstable or may affect participant safety, assessment of study endpoints, assessment of immune response, or adherence to study procedures.
• Receipt of the COVID-19 vaccine within 6 months prior to enrollment.
• Receipt of any licensed non-COVID-19 vaccine within 28 days before or planned receipt within 28 days after the study intervention, except an influenza vaccine, which may be given 14 days before or after receipt of the study intervention.
• Receipt of systemic immunosuppressants for \>14 days in total, within 180 days prior to Screening Visit (for corticosteroids ≥10 milligrams \[mg\]/day of prednisone equivalent) or is anticipating the need for immunosuppressive treatment at any time during participation in the study.
• Receipt of systemic immunoglobulins, long-acting biological therapies that affect immune responses (for example, infliximab) or blood products within 90 days prior to the Screening Visit or plans to receive them during the study.
• History of anaphylaxis or severe hypersensitivity reaction requiring medical intervention after receipt of any mRNA vaccine or therapeutic or any components of an mRNA vaccine or therapeutic.
• Has donated ≥450 milliliters (mL) of blood products within 28 days prior to the Screening Visit or plans to donate blood products within 28 days after the study injection.

Sponsors & Collaborators

• ModernaTX, Inc.: lead

Study Sites (5)

DelRicht Research-Atlanta

Atlanta, Georgia, 30329, United States

Location

DelRicht Research-Baton Rouge

Baton Rouge, Louisiana, 70769, United States

Location

DelRicht Research-New Orleans

New Orleans, Louisiana, 70115, United States

Location

DelRicht Research-Gulfport

Gulfport, Mississippi, 39503, United States

Location

DelRicht Research-Tulsa

Tulsa, Oklahoma, 74133, United States

Location

MeSH Terms

Conditions

COVID-19; Coronavirus Infections; Virus Diseases

Condition Hierarchy (Ancestors)

Pneumonia, Viral; Pneumonia; Respiratory Tract Infections; Infections; Coronaviridae Infections; Nidovirales Infections; RNA Virus Infections; Lung Diseases; Respiratory Tract Diseases

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: NA
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: This is a Phase 3b/4 open-label study.

Study Record Dates

• First Submitted: July 21, 2025
• First Posted: July 28, 2025
• Study Start: July 21, 2025
• Primary Completion: June 16, 2026
• Study Completion: June 16, 2026
• Last Updated: July 7, 2026

Record last verified: 2026-06

Locations

US (5)