NCT05960097

A Study on the Safety and Immune Response of Investigational COVID-19 mRNA Vaccines in Healthy Adults

A Phase 2 Randomized, Active-controlled, Observer-blind Study to Assess the Safety, Reactogenicity, and Immunogenicity of a Booster Dose of Investigational COVID-19 mRNA Vaccines in Healthy Adults Who Previously Received a Complete Primary Vaccination Series With or Without Booster Dose(s)

• Status: Completed
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 692 (actual)
• Sponsor: GlaxoSmithKline · Industry
• Sex: All
• Age: 18 Years
• Healthy volunteers: Accepted

Summary

The purpose of Part A of this study is to assess the immune response and safety of a booster dose of investigational COVID-19 mRNA vaccines in healthy adults. The study will compare the investigational vaccines to control vaccine. The purpose of Part B of this study is to assess the immune response and safety of a booster dose of investigational COVID-19 mRNA vaccines in healthy adults. The study will compare the investigational vaccine under three different storage conditions.

Detailed description

Part A: This Phase 2 study's Part A evaluates the safety, reactogenicity, and immunogenicity of two candidate vaccines - the bivalent CV0701 and the monovalent CV0601 - in healthy adults who have received a full primary vaccination series (with or without booster doses). By including these candidates, the study will assess whether immune interference occurs between the XY spike protein and the XX spike protein antigens in the bivalent vaccine compared with the XX spike protein antigen in the monovalent vaccine. In Part A, both CV0701 and CV0601 will be compared to the Control Vaccine (that serve as a standard of care control) using a randomized, observer-blinded design. Part B: The purpose of Part B is to evaluate the safety and Day 29 immunogenicity of CV0801 under three storage conditions: * Condition 1: Baseline/control * Condition 2: Intermediate storage * Condition 3: Maximum storage Condition 1 serves as the control against which the performance (safety, reactogenicity, and immunogenicity) of Conditions 2 and 3 will be compared. mRNA vaccine stability is affected by product-specific factors (e.g., molecular weight, buffer composition, lipid nanoparticle encapsulation), manufacturing factors (such as the duration the vaccine remains in liquid form during production and handling at different temperatures), and storage conditions. The impact of these factors is based on product and process knowledge as well as clinical experience. Through Part B of this Phase 2 study, GSK and CureVac aim to develop data on how different storage conditions affect the final attributes of the vaccine in a clinical trial setting.

Conditions

• SARS-CoV-2
• COVID-19

Interventions

Type	Name	Description
BIOLOGICAL	CV0701 mRNA COVID-19 Vaccine (Low dose)	Study vaccine was administered as a single intramuscular injection.
BIOLOGICAL	CV0701 mRNA COVID-19 Vaccine (Medium dose)	Study vaccine was administered as a single intramuscular injection.
BIOLOGICAL	CV0701 mRNA COVID-19 Vaccine (High dose)	Study vaccine was administered as a single intramuscular injection.
BIOLOGICAL	CV0601 mRNA COVID-19 Vaccine	Study vaccine was administered as a single intramuscular injection.
BIOLOGICAL	Control vaccine	Study vaccine was administered as a single intramuscular injection.
BIOLOGICAL	CV0801 mRNA COVID-19 Vaccine	Study vaccine was administered as a single intramuscular injection.

Timeline

• Start date: 2023-08-01
• Primary completion: 2024-08-30
• Completion: 2024-08-30
• First posted: 2023-07-25
• Last updated: 2025-10-23
• Results posted: 2025-10-23

Locations

17 sites across 2 countries: United States, Australia

Regulatory

• FDA-regulated drug study