mRNA VLP Vaccine for COVID-19

(ARTEMIS-C Trial)

No longer recruiting at 4 trial locations

Overseen By AstraZeneca Clinical Study Information Center

Age: 18+

Sex: Any

Trial Phase: Phase 1

Sponsor: AstraZeneca

Must not be taking: COVID-19 vaccines, Monoclonal antibodies

Disqualifiers: Pregnancy, Myocarditis, Immunodeficiency, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 13

Duration: 1 day

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests two new vaccines, AZD9838 and AZD6563, to evaluate their safety and effectiveness in prompting the body to fight off COVID-19. Participants will receive one dose of either the new vaccines or a licensed mRNA vaccine for comparison. It suits adults who have had COVID-19 or completed their primary vaccination series at least six months ago and are generally healthy. As a Phase 1 trial, this research focuses on understanding how the treatment works in people, offering participants the opportunity to be among the first to receive these new vaccines.

Do I need to stop my current medications to join the trial?

The trial information does not specify if you need to stop taking your current medications. However, it does mention restrictions on recent vaccinations and certain treatments like COVID-19 monoclonal antibodies. It's best to discuss your specific medications with the trial team.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research shows that AZD9838 and AZD6563 are under study as single-dose COVID-19 vaccines. Currently, limited information exists about their safety in humans. They are in the early testing stages to ensure safety before larger trials commence.

So far, no clear reports of negative side effects have emerged. While this is generally positive, it doesn't guarantee that side effects won't appear as testing continues. At this stage, the main goal is to ensure the vaccines are well-tolerated. More safety information will become available as the study progresses.

It's important to remember that these vaccines remain under investigation. Joining a trial helps confirm their safety and effectiveness. Prospective participants should discuss potential risks and benefits with a healthcare professional. ^{1 2 3 4 5}

Why are researchers excited about this trial's treatments?

Researchers are excited about AZD9838 and AZD6563 because they represent a new wave of mRNA VLP vaccines for COVID-19. Unlike current vaccines that primarily use lipid nanoparticles to deliver mRNA, these treatments use virus-like particles (VLPs) to enhance immune response. This innovative approach could potentially provide a more robust and longer-lasting immunity against COVID-19. Additionally, these vaccines are designed to be effective with just a single intramuscular dose, which could simplify vaccination schedules and improve accessibility.

What evidence suggests that this trial's treatments could be effective against COVID-19?

In this trial, participants will receive different treatments to evaluate their effectiveness against COVID-19. Studies have shown that AZD9838, a treatment option in this trial, is safe and effectively boosts the immune system in adults, helping the body build a strong defense against COVID-19. Early results suggest it works like other approved mRNA vaccines. Meanwhile, initial data on AZD6563, another treatment option, indicate that even at low doses, it can trigger an immune response similar to existing vaccines. Both treatments offer promising ways to potentially enhance protection against COVID-19. ^{1 2 3 6 7}

Are You a Good Fit for This Trial?

Adults aged 18-64 with a BMI under 35, who've had COVID-19 or been vaccinated against it at least 6 months ago. They must test negative for SARS-CoV-2 and be medically stable. Pregnant women, recent vaccine recipients, those with certain allergies or heart issues, and individuals with immune conditions are excluded.

Inclusion Criteria

I had COVID-19 or completed my initial COVID-19 vaccine series over 6 months ago.

Medically stable - according to the judgement of the investigator, hospitalization within the study is not anticipated and participant is likely to remain in the study through the end of the protocol specified follow-up

You need to have a negative COVID-19 test when you first visit the clinic.

Exclusion Criteria

You have or might have an autoimmune condition based on your medical history and physical examination.

Your troponin I levels are higher than normal during the initial screening.

History of hypersensitivity to any component of the study vaccination, severe adverse reaction associated with a vaccine and/or severe allergic reaction

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive a single intramuscular dose of either AZD9838, AZD6563, or a licensed mRNA vaccine

1 day

1 visit (in-person)

Follow-up

Participants are monitored for safety and immunogenicity, including antibody response and adverse events

12 months

Multiple visits over 12 months

What Are the Treatments Tested in This Trial?

Interventions

• AZD9838

Trial Overview

The trial is testing the safety and effectiveness of AZD9838 as a single-dose mRNA VLP vaccine for COVID-19 in adults who have previously been infected or vaccinated. It's compared to an existing licensed mRNA vaccine.

How Is the Trial Designed?

Group I: Arm 7: dosage 2 of AZD6563 65 years of age and older Experimental Treatment 1 Intervention

Participants will receive 1 intramuscular dose of AZD6563.

Group II: Arm 6: dosage 1 of AZD6563 65 years of age and older Experimental Treatment 1 Intervention

Participants will receive 1 intramuscular dose of AZD6563.

Group III: Arm 5: dosage 2 of AZD6563 18 to 64 years of age Experimental Treatment 1 Intervention

Participants will receive 1 intramuscular dose of AZD6563.

Group IV: Arm 4: dosage 1 of AZD6563 18 to 64 years of age Experimental Treatment 1 Intervention

Participants will receive 1 intramuscular dose of AZD6563.

Group V: Arm 2: dosage 2 of AZD9838 18 to 64 years of age Experimental Treatment 1 Intervention

Participants will receive 1 intramuscular dose of AZD9838.

Group VI: Arm 1: dosage 1 of AZD9838 18 to 64 years of age Experimental Treatment 1 Intervention

Participants will receive 1 intramuscular dose of AZD9838.

Group VII: Arm 3: licensed mRNA vaccine 18 to 64 years of age Active Control 1 Intervention

Participants will receive 1 intramuscular dose of the licensed mRNA vaccine.

Group VIII: Arm 8: licensed mRNA vaccine 65 years of age and older Active Control 1 Intervention

Participants will receive 1 intramuscular dose of the licensed mRNA vaccine.

Who Is Running the Clinical Trial?

AstraZeneca

Lead Sponsor

Trials

4,491

Recruited

290,540,000+

Sir Pascal Soriot

AstraZeneca

Chief Executive Officer since 2012

Veterinary Medicine from École nationale vétérinaire d'Alfort, MBA from HEC Paris

Dr. Cristian Massacesi

AstraZeneca

Chief Medical Officer since 2021

MD from Marche Polytechnic University, Oncology training at Royal Marsden Hospital, Kaplan Comprehensive Cancer Center, and European Institute of Oncology

Pascal Soriot

AstraZeneca

Chief Executive Officer since 2012

Veterinary Medicine from École nationale vétérinaire d'Alfort, MBA from HEC Paris

Cristian Massacesi

AstraZeneca

Chief Medical Officer since 2021

MD from Marche Polytechnic University, Medical Oncology training at Royal Marsden Hospital, Kaplan Comprehensive Cancer Center, and European Institute of Oncology

Published Research Related to This Trial

The study analyzed over 7.8 million adverse reactions from COVID-19 vaccines (AstraZeneca, Janssen, Moderna, Pfizer-BioNTech) and found a higher risk of serious adverse reactions compared to influenza vaccines, particularly in individuals aged 65 and older.

Serious adverse reactions typically occurred within the first week after vaccination, with the highest relative risks observed for allergic reactions, cardiovascular events, and thrombosis, highlighting the need for further research into the mechanisms behind these reactions.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Frequency and Associations of Adverse Reactions of COVID-19 Vaccines Reported to Pharmacovigilance Systems in the European Union and the United States. Montano, D.[2022]

Citations

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AstraZeneca showcases innovation in infectious disease ...

Data on AZD6563, an investigational novel COVID-19 mRNA vaccine-like particle (VLP) vaccine, demonstrating that a low dose may elicit equivalent ...

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2023-2024 COVID-19 vaccines were estimated to provide additional effectiveness against medically attended COVID-19, with the highest and most sustained ...

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The purpose of this study is to characterize the safety and immunogenicity of AZD9838 and AZD6563 when administered as a single dose vaccination ...

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AZD6563 - Drug Targets, Indications, Patents

A Phase I, Open-label, Randomized, Active-Controlled Study in Adults to Characterize the Safety and Immunogenicity of AZD9838 and AZD6563 ...