CompletedPhase 1

Safety and Immunogenicity Study of Self-Amplifying RNA Pandemic Influenza Vaccine in Adults

United States212 participantsStarted 2024-12-10

Plain-language summary

The goal of this clinical trial is to evaluate the safety and immune responses of three different dose levels a self-amplifying RNA pandemic influenza vaccine (ARCT-2304) in adults. The key objectives of the study are: * To evaluate safety and reactogenicity of different dose levels of the ARCT-2304 vaccine * To describe the Immune responses of different dose levels of the ARCT-2304 vaccine as measured by hemagglutination inhibition (HAI) and neuraminidase enzyme-linked lectin (ELLA) antibody responses Researchers will compare the results with licensed influenza vaccines to select the most optimal dose level and schedule for vaccine administration in terms of safety and immunogenicity for further development of the vaccine. Participants will receive 2 doses of the ARCT-2304 vaccine or 1 dose of licensed influenza vaccine and 1 dose of placebo. They will be asked: * to complete a daily diary for 7 days after each vaccination, answering questions how they have been feeling on that day. * to provide blood samples at each visit in the clinic * to comply with all study visits and procedures (e.g., be available for planned telephone contacts and unscheduled clinic visits, if required)

Who can participate

Age range

18 Years – 80 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Main Inclusion Criteria: * Individuals are male or female adults 18-80 years of age. * Healthy participants or participants with pre-existing stable medical conditions. * Individuals of childbearing potential must be willing to adhere to contraceptive requirements. Main Exclusion Criteria: * Individuals with acute medical conditions or febrile illness, including body temperature ≥100.4°F (≥38.0°C measured by any method) within 3 days prior to randomization. * Individuals with a known history of severe hypersensitivity reactions, including anaphylaxis, or other significant adverse reactions to any mRNA vaccine, influenza vaccine, or excipients. * Individuals with a history of myocarditis, pericarditis, myopericarditis, or cardiomyopathy. * Individuals who received any influenza vaccine within 3 months prior to first vaccine administration or plan to receive an influenza vaccine during the study period. * Individuals who have received mRNA vaccination within 60 days before the first vaccine administration. * Individuals who have received or plan to receive an A/H5N1 influenza vaccine and/or individuals who had substantial exposure to or direct contact with poultry, wild birds, live cattle, or raw milk.

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

Percentage of participants reporting local Adverse Events

Timeframe: For 7 days following each study vaccination

Percentage of participants reporting systemic Adverse Events

Timeframe: For 7 days following each study vaccination

Percentage of participants reporting unsolicited Adverse Events

Timeframe: For 28 days following each study vaccination

Percentage of participants reporting laboratory or vital signs abnormalities

Timeframe: For 28 days following each study vaccination

Percentage of participants reporting serious adverse events, medically attended adverse events, adverse events of special interest, and adverse events leading to early termination

Timeframe: For 28 days following each study vaccination

Serum hemagglutination inhibition (HAI) antibody levels against the HA glycoprotein

Timeframe: For 28 days following study second vaccination

Trial details

NCT IDNCT06602531

SponsorArcturus Therapeutics, Inc.

Sponsor typeINDUSTRY

Study typeINTERVENTIONAL

Primary completion2025-06-13

View on ClinicalTrials.gov More Influenza, Human trials

Plain-language summary

Who can participate

Age range

18 Years – 80 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

What they're measuring

Percentage of participants reporting local Adverse Events

Timeframe: For 7 days following each study vaccination

Percentage of participants reporting systemic Adverse Events

Timeframe: For 7 days following each study vaccination

Percentage of participants reporting unsolicited Adverse Events

Timeframe: For 28 days following each study vaccination

Percentage of participants reporting laboratory or vital signs abnormalities

Timeframe: For 28 days following each study vaccination

Percentage of participants reporting serious adverse events, medically attended adverse events, adverse events of special interest, and adverse events leading to early termination

Timeframe: For 28 days following each study vaccination

Serum hemagglutination inhibition (HAI) antibody levels against the HA glycoprotein

Timeframe: For 28 days following study second vaccination