Safety and Immunogenicity Study of Self-Amplifying RNA Pandemic Influenza Vaccine in Adults
August 12, 2026 updated by: Arcturus Therapeutics, Inc.
A Phase 1, First-in-human, Randomized, Observer-blind, Parallel Design, Controlled, Dose Level and Schedule-finding Study to Evaluate the Safety, Reactogenicity, and Immunogenicity of a Self-Amplifying mRNA Pandemic Influenza Vaccine (ARCT-2304) When Administered to Healthy Adults
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)
Study Overview
Status
Completed
Conditions
Detailed Description
Phase 1, first-in-human, randomized, controlled, observer blind, dose level and schedule-finding study, to evaluate the safety, reactogenicity, and immunogenicity of a self-amplifying mRNA pandemic influenza (H5N1) vaccine (ARCT-2304) when administered as a 2-dose vaccination series to healthy adults in comparison with an inactivated influenza vaccine.
Study drug (ARCT-2304 or control) will be administered as a 2-dose vaccination series as an intramuscular (IM) injection. The study comprises two parts.
In Part 1, 120 participants (young adults) will be randomized to one of the three dose levels of the ARCT-2304 vaccine or control vaccine. Participants will be further randomized to one of the two different vaccination schedules.
In Part 2, 80 participants (older adults) will be randomized to one of the three dose levels of the ARCT-2304 vaccine or control vaccine. Participants will be further randomized to one of the two different vaccination schedules.
Investigational Vaccine: ARCT-2304
Control Vaccines: licensed influenza vaccines
Study Type
Interventional
Enrollment (Actual)
212
Phase
- Phase 2
- Phase 1
Contacts and Locations
This section provides the contact details for those conducting the study, and information on where this study is being conducted.
Study Locations
-
-
California
-
La Mesa, California, United States, 91942
- Velocity Clinical Research
-
San Bernardino, California, United States, 92408
- Velocity Clinical Research
-
-
Colorado
-
Longmont, Colorado, United States, 80501
- Tekton Research
-
-
Ohio
-
Cincinnati, Ohio, United States, 45212
- CTI Clinical Research Center
-
-
Participation Criteria
Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.
Eligibility Criteria
Ages Eligible for Study
- Adult
- Older Adult
Accepts Healthy Volunteers
Yes
Description
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.
Study Plan
This section provides details of the study plan, including how the study is designed and what the study is measuring.
How is the study designed?
Design Details
- Primary Purpose: Prevention
- Allocation: Randomized
- Interventional Model: Parallel Assignment
- Masking: Quadruple
Arms and Interventions
Participant Group / Arm |
Intervention / Treatment |
|---|---|
|
Experimental: Low dose of ARCT-2304, Schedule 1, Young Adults
Low dose of ARCT-2304 administered through intramuscular injection in the deltoid muscle. Interventions: 2-dose regimen, schedule 1 Investigational Vaccine: ARCT-2304 |
Each participant will receive 2-dose regimen intramuscular (IM) dose into the deltoid muscle.
Other Names:
|
|
Experimental: Mid dose of ARCT-2304, Schedule 1, Young Adults
Mid dose of ARCT-2304 administered through intramuscular injection in the deltoid muscle. Interventions: 2-dose regimen, schedule 1 Investigational Vaccine: ARCT-2304 |
Each participant will receive 2-dose regimen intramuscular (IM) dose into the deltoid muscle.
Other Names:
|
|
Experimental: High dose of ARCT-2304, Schedule 1, Young Adults
High dose of ARCT-2304 administered through intramuscular injection in the deltoid muscle. Interventions: 2-dose regimen, schedule 1 Investigational Vaccine: ARCT-2304 |
Each participant will receive 2-dose regimen intramuscular (IM) dose into the deltoid muscle.
Other Names:
|
|
Active Comparator: Control, Schedule 1, Young Adults
Control Vaccine (dose 1) and placebo (dose 2) administered through intramuscular injection in the deltoid muscle. Interventions: 2-dose regimen, schedule 1 Investigational Vaccine: Comparator vaccine younger adult and saline placebo vaccine |
Each participant will receive one intramuscular (IM) dose into the deltoid muscle.
Other Names:
Each participant will receive one intramuscular (IM) dose into the deltoid muscle.
Other Names:
|
|
Experimental: Low dose of ARCT-2304, Schedule 1, Older Adults
Low dose of ARCT-2304 administered through intramuscular injection in the deltoid muscle. Interventions: 2-dose regimen, schedule 1 Investigational Vaccine: ARCT-2304 |
Each participant will receive 2-dose regimen intramuscular (IM) dose into the deltoid muscle.
Other Names:
|
|
Experimental: Mid dose of ARCT-2304, Schedule 1, Older Adults
Mid dose of ARCT-2304 administered through intramuscular injection in the deltoid muscle. Interventions: 2-dose regimen, schedule 1 Investigational Vaccine: ARCT-2304 |
Each participant will receive 2-dose regimen intramuscular (IM) dose into the deltoid muscle.
Other Names:
|
|
Experimental: High dose of ARCT-2304, Schedule 1, Older Adults
High dose of ARCT-2304 administered through intramuscular injection in the deltoid muscle. Interventions: 2-dose regimen, schedule 1 Investigational Vaccine: ARCT-2304 |
Each participant will receive 2-dose regimen intramuscular (IM) dose into the deltoid muscle.
Other Names:
|
|
Active Comparator: Control, Schedule 1, Older Adults
Older Adults Control Vaccine (dose 1) and placebo (dose 2) administered through intramuscular injection in the deltoid muscle. Interventions: 2-dose regimen, schedule 1 Investigational Vaccine: Comparator vaccine older adult and saline |
Each participant will receive one intramuscular (IM) dose into the deltoid muscle.
Other Names:
Each participant will receive one intramuscular (IM) dose into the deltoid muscle.
Other Names:
|
|
Experimental: Low dose of ARCT-2304, Schedule 2, Young Adults
Low dose of ARCT-2304 administered through intramuscular injection in the deltoid muscle. Interventions: 2-dose regimen, schedule 2 Investigational Vaccine: ARCT-2304 |
Each participant will receive 2-dose regimen intramuscular (IM) dose into the deltoid muscle.
Other Names:
|
|
Experimental: Mid dose of ARCT-2304, Schedule 2, Young Adults
Mid dose of ARCT-2304 administered through intramuscular injection in the deltoid muscle. Interventions: 2-dose regimen, schedule 2 Investigational Vaccine: ARCT-2304 |
Each participant will receive 2-dose regimen intramuscular (IM) dose into the deltoid muscle.
Other Names:
|
|
Experimental: High dose of ARCT-2304, Schedule 2, Young Adults
High dose of ARCT-2304 administered through intramuscular injection in the deltoid muscle. Interventions: 2-dose regimen, schedule 2 Investigational Vaccine: ARCT-2304 |
Each participant will receive 2-dose regimen intramuscular (IM) dose into the deltoid muscle.
Other Names:
|
|
Active Comparator: Control, Schedule 2, Young Adults
Young Adults Control Vaccine (dose 1) and placebo (dose 2) administered through intramuscular injection in the deltoid muscle. Interventions: 2-dose regimen, schedule 2 Investigational Vaccine: Comparator vaccine younger adult and saline placebo vaccine |
Each participant will receive one intramuscular (IM) dose into the deltoid muscle.
Other Names:
Each participant will receive one intramuscular (IM) dose into the deltoid muscle.
Other Names:
|
|
Experimental: Low dose of ARCT-2304, Schedule 2, Older Adults
Low dose of ARCT-2304 administered through intramuscular injection in the deltoid muscle. Interventions: 2-dose regimen, schedule 2 Investigational Vaccine: ARCT-2304 |
Each participant will receive 2-dose regimen intramuscular (IM) dose into the deltoid muscle.
Other Names:
|
|
Experimental: Mid dose of ARCT-2304, Schedule 2, Older Adults
Mid dose of ARCT-2304 administered through intramuscular injection in the deltoid muscle. Interventions: 2-dose regimen, schedule 2 Investigational Vaccine: ARCT-2304 |
Each participant will receive 2-dose regimen intramuscular (IM) dose into the deltoid muscle.
Other Names:
|
|
Experimental: High dose of ARCT-2304, Schedule 2, Older Adults
High dose of ARCT-2304 administered through intramuscular injection in the deltoid muscle. Interventions: 2-dose regimen, schedule 2 Investigational Vaccine: ARCT-2304 |
Each participant will receive 2-dose regimen intramuscular (IM) dose into the deltoid muscle.
Other Names:
|
|
Active Comparator: Control, Schedule 2, Older Adults
Older Adults Control Vaccine (dose 1) and placebo (dose 2) administered through intramuscular injection in the deltoid muscle. Interventions: 2-dose regimen, schedule 2 Investigational Vaccine: Comparator vaccine older adult and saline placebo vaccine |
Each participant will receive one intramuscular (IM) dose into the deltoid muscle.
Other Names:
Each participant will receive one intramuscular (IM) dose into the deltoid muscle.
Other Names:
|
What is the study measuring?
Primary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
|---|---|---|
|
Number of Participants With Solicited Adverse Events (AEs) Within 7 Days After Each Vaccination
Time Frame: 7 days post each dose
|
The following solicited local and systemic AEs were recorded from Day 1 to 7 days after each vaccination (dose): Injection site pain, Erythema, Swelling, Fatigue, Headache, Myalgia, Arthralgia, Dizziness, Nausea, Chills, Fever (≥100.4
°Fahrenheit [F] /≥38.0 °Celsius [C]).
A summary of all Serious Adverse Events and Other Adverse Events (non-serious) regardless of causality is located in the 'Reported Adverse Events' Section.
|
7 days post each dose
|
|
Number of Participants With Unsolicited AEs Within 28 Days After Each Vaccination
Time Frame: D1,29 Cohorts: up to Day 29 and up to Day 57 (28 days post each dose), D1,57 Cohorts: up to Day 29 and up to Day 85 (28 days post each dose)
|
An AE was any untoward medical occurrence in a participant or participant administered a medicinal product, whether or not considered related to the trial vaccine.
An unsolicited AE was defined as any AE not included in the list of solicited AEs (i.e., any event other than injection site pain, erythema, swelling, fatigue, headache, myalgia, arthralgia, dizziness, nausea, chills, or fever (≥100.4
°F / ≥38.0 °C).
Solicited AEs that lasted for more than 7 days were considered as unsolicited AEs.
Unsolicited AEs were recorded from Day 1 up to 28 days after each vaccination (dose).
A summary of all Serious Adverse Events and Other Adverse Events (non-serious) regardless of causality is located in the 'Reported Adverse Events' Section'.
|
D1,29 Cohorts: up to Day 29 and up to Day 57 (28 days post each dose), D1,57 Cohorts: up to Day 29 and up to Day 85 (28 days post each dose)
|
|
Number of Participants With Serious Adverse Events (SAEs), Medically Attended AEs (MAAEs), AEs of Special Interest (AESIs), and AEs Leading To Early Termination From Day 1 to 28 Days After Second Vaccination
Time Frame: D1,29 Cohorts: up to Day 57, D1,57 Cohorts: up to Day 85
|
An SAE was defined as any AE that resulted in death, was life-threatening, resulted in persistent disability/incapacity, or required inpatient hospitalization or prolongation of existing hospitalization.
AEs potentially associated with messenger ribonucleic acid (mRNA) vaccines and influenza vaccines were reported as AESIs.
MAAEs were defined as AEs with medically attended visits including hospital, emergency room, urgent care clinic, or other visits (including phone/telehealth visits) to or from medical personnel for any reason but did not fulfil seriousness criteria.
A summary of all Serious Adverse Events and Other Adverse Events (non-serious) regardless of causality is located in the 'Reported Adverse Events' Section'.
|
D1,29 Cohorts: up to Day 57, D1,57 Cohorts: up to Day 85
|
|
Geometric Mean Titer of Antibody Response to Hemagglutinin (HA) Glycoprotein Measured By Hemagglutinin Inhibition (HAI) Assay
Time Frame: D1,29 Cohorts: Day 1, Day 29 (28 days post dose 1), Day 36 (7 days post dose 2), and Day 57 (28 days post dose 2), D1,57 Cohorts: Day 1, Day 57 (56 days post dose 1), Day 64 (7 days post dose 2), and Day 85 (28 days post dose 2)
|
A serum HAI assay was used for measuring HA-specific antibodies against the A/H5N1/Indonesia/5/2005 influenza strain.
Antibody titers were expressed as Geometric Mean Titers.
|
D1,29 Cohorts: Day 1, Day 29 (28 days post dose 1), Day 36 (7 days post dose 2), and Day 57 (28 days post dose 2), D1,57 Cohorts: Day 1, Day 57 (56 days post dose 1), Day 64 (7 days post dose 2), and Day 85 (28 days post dose 2)
|
|
Geometric Mean Titer of Antibody Response to Neuraminidase (NA) Glycoprotein Measured By Enzyme-linked Lectin Assay (ELLA)
Time Frame: D1,29 Cohorts: Day 1, Day 29 (28 days post dose 1), Day 36 (7 days post dose 2), and Day 57 (28 days post dose 2), D1,57 Cohorts: Day 1, Day 57 (56 days post dose 1), Day 64 (7 days post dose 2), and Day 85 (28 days post dose 2)
|
A serum ELLA assay was used for measuring NA-specific antibodies against the A/H5N1/Indonesia/5/2005 influenza strain.
Antibody titers were expressed as Geometric Mean Titers.
|
D1,29 Cohorts: Day 1, Day 29 (28 days post dose 1), Day 36 (7 days post dose 2), and Day 57 (28 days post dose 2), D1,57 Cohorts: Day 1, Day 57 (56 days post dose 1), Day 64 (7 days post dose 2), and Day 85 (28 days post dose 2)
|
|
Geometric Mean Fold Rise of Antibody Response to HA Glycoprotein Measured By HAI Assay
Time Frame: D1,29 Cohorts: Day 29 (28 days post dose 1), Day 36 (7 days post dose 2), and Day 57 (28 days post dose 2), D1,57 Cohorts: Day 57 (56 days post dose 1), Day 64 (7 days post dose 2), and Day 85 (28 days post dose 2)
|
A serum HAI assay was used for measuring HA-specific antibodies against the A/H5N1/Indonesia/5/2005 influenza strain.
Geometric Mean Fold Rise was reported as a ratio to Day 1.
|
D1,29 Cohorts: Day 29 (28 days post dose 1), Day 36 (7 days post dose 2), and Day 57 (28 days post dose 2), D1,57 Cohorts: Day 57 (56 days post dose 1), Day 64 (7 days post dose 2), and Day 85 (28 days post dose 2)
|
|
Geometric Mean Fold Rise of Antibody Response to NA Glycoprotein Measured By ELLA
Time Frame: D1,29 Cohorts: Day 29 (28 days post dose 1), Day 36 (7 days post dose 2), and Day 57 (28 days post dose 2), D1,57 Cohorts: Day 57 (56 days post dose 1), Day 64 (7 days post dose 2), and Day 85 (28 days post dose 2)
|
A serum ELLA assay was used for measuring NA-specific antibodies against the A/H5N1/Indonesia/5/2005 influenza strain.
Geometric Mean Fold Rise was reported as a ratio to Day 1.
|
D1,29 Cohorts: Day 29 (28 days post dose 1), Day 36 (7 days post dose 2), and Day 57 (28 days post dose 2), D1,57 Cohorts: Day 57 (56 days post dose 1), Day 64 (7 days post dose 2), and Day 85 (28 days post dose 2)
|
|
Percentage of Participants With Seroconversion of Antibody Response to HA Glycoprotein Measured By HAI Assay
Time Frame: D1,29 Cohorts: Day 29 (28 days post dose 1), Day 36 (7 days post dose 2), and Day 57 (28 days post dose 2), D1,57 Cohorts: Day 57 (56 days post dose 1), Day 64 (7 days post dose 2), and Day 85 (28 days post dose 2)
|
A serum HAI assay was used for measuring HA-specific antibodies against the A/H5N1/Indonesia/5/2005 influenza strain.
Seroconversion was recorded if participant had pre-vaccination antibody titer < Lower Limit Of Quantitation (LLOQ) and a post-vaccination antibody titer ≥ 4 x LLOQ, or a pre-vaccination antibody titer ≥LLOQ and a ≥4-fold increase in post-vaccination antibody titer.
|
D1,29 Cohorts: Day 29 (28 days post dose 1), Day 36 (7 days post dose 2), and Day 57 (28 days post dose 2), D1,57 Cohorts: Day 57 (56 days post dose 1), Day 64 (7 days post dose 2), and Day 85 (28 days post dose 2)
|
|
Percentage of Participants With Seroconversion of Antibody Response to NA Glycoprotein Measured By ELLA
Time Frame: D1,29 Cohorts: Day 29 (28 days post dose 1), Day 36 (7 days post dose 2), and Day 57 (28 days post dose 2), D1,57 Cohorts: Day 57 (56 days post dose 1), Day 64 (7 days post dose 2), and Day 85 (28 days post dose 2)
|
A serum ELLA assay was used for measuring NA-specific antibodies against the A/H5N1/Indonesia/5/2005 influenza strain.
Seroconversion was recorded if participant had pre-vaccination antibody titer < LLOQ and a post-vaccination antibody titer ≥ 4 x LLOQ, or a pre-vaccination antibody titer ≥LLOQ and a ≥4-fold increase in post-vaccination antibody titer.
|
D1,29 Cohorts: Day 29 (28 days post dose 1), Day 36 (7 days post dose 2), and Day 57 (28 days post dose 2), D1,57 Cohorts: Day 57 (56 days post dose 1), Day 64 (7 days post dose 2), and Day 85 (28 days post dose 2)
|
|
Percentage of Participants With HAI Titers Above or Equal to Prespecified Thresholds
Time Frame: D1,29 Cohorts: Day 57 (28 days post dose 2), D1,57 Cohorts: Day 85 (28 days post dose 2)
|
A serum HAI assay was used for measuring HA-specific antibodies against the A/H5N1/Indonesia/5/2005 influenza strain.
The prespecified antibody threshold levels were as follows: ≥1:10, ≥1:20, ≥1:40, ≥1:80, ≥1:160, and ≥1:320.
|
D1,29 Cohorts: Day 57 (28 days post dose 2), D1,57 Cohorts: Day 85 (28 days post dose 2)
|
|
Percentage of Participants With ELLA Titers Above or Equal to Prespecified Thresholds
Time Frame: D1,29 Cohorts: Day 57 (28 days post dose 2), D1,57 Cohorts: Day 85 (28 days post dose 2)
|
A serum ELLA assay was used for measuring NA-specific antibodies against the A/H5N1/Indonesia/5/2005 influenza strain.
The prespecified antibody threshold levels were as follows: ≥1:10, ≥1:20, ≥1:40, ≥1:80, ≥1:160, and ≥1:320.
|
D1,29 Cohorts: Day 57 (28 days post dose 2), D1,57 Cohorts: Day 85 (28 days post dose 2)
|
Secondary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
|---|---|---|
|
Number of Participants With SAEs, MAAEs, AESIs, and AEs Leading To Early Termination From Day 1 to Day 240
Time Frame: Day 1 to Day 240
|
A SAE was defined as any AE that resulted in death, was life-threatening, resulted in persistent disability/incapacity, or required inpatient hospitalization or prolongation of existing hospitalization.
AEs potentially associated with mRNA vaccines and influenza vaccines were reported as AESIs.
MAAEs were defined as AEs with medically attended visits including hospital, emergency room, urgent care clinic, or other visits (including phone/telehealth visits) to or from medical personnel for any reason, but did not fulfil seriousness criteria.
A summary of all Serious Adverse Events and Other Adverse Events (non-serious) regardless of causality is located in the 'Reported Adverse Events' Section.
|
Day 1 to Day 240
|
|
Geometric Mean Titer of Antibody Response To HA Glycoprotein Measured By HAI Assay at Day 240
Time Frame: Day 240
|
A serum HAI assay was used for measuring HA-specific antibodies against the A/H5N1/Indonesia/5/2005 influenza strain.
Antibody titers were expressed as Geometric Mean Titers.
|
Day 240
|
|
Geometric Mean Titer of Antibody Response to NA Glycoprotein Measured By ELLA at Day 240
Time Frame: Day 240
|
A serum ELLA assay was used for measuring NA-specific antibodies against the A/H5N1/Indonesia/5/2005 influenza strain.
Antibody titers were expressed as Geometric Mean Titers.
|
Day 240
|
|
Geometric Mean Fold Rise of Antibody Response to HA Glycoprotein Measured By HAI Assay at Day 240
Time Frame: Day 240
|
A serum HAI assay was used for measuring HA-specific antibodies against the A/H5N1/Indonesia/5/2005 influenza strain.
Geometric Mean Fold Rise was reported as a ratio to Day 1.
|
Day 240
|
|
Geometric Mean Fold Rise of Antibody Response to NA Glycoprotein Measured By ELLA at Day 240
Time Frame: Day 240
|
A serum ELLA assay was used for measuring NA-specific antibodies against the A/H5N1/Indonesia/5/2005 influenza strain.
Geometric Mean Fold Rise was reported as a ratio to Day 1.
|
Day 240
|
|
Percentage of Participants With Seroconversion of Antibody Response to HA Glycoprotein Measured By HAI Assay At Day 240
Time Frame: Day 240
|
A serum HAI assay was used for measuring HA-specific antibodies against the A/H5N1/Indonesia/5/2005 influenza strain.
Seroconversion was recorded if participant had pre-vaccination antibody titer < LLOQ and a post-vaccination antibody titer ≥ 4 x LLOQ, or a pre-vaccination antibody titer ≥LLOQ and a ≥4-fold increase in post-vaccination antibody titer.
|
Day 240
|
|
Percentage of Participants With Seroconversion of Antibody Response to NA Glycoprotein Measured By ELLA At Day 240
Time Frame: Day 240
|
A serum ELLA assay was used for measuring NA-specific antibodies against the A/H5N1/Indonesia/5/2005 influenza strain.
Seroconversion was recorded if participant had pre-vaccination antibody titer < LLOQ and a post-vaccination antibody titer ≥ 4 x LLOQ, or a pre-vaccination antibody titer ≥LLOQ and a ≥4-fold increase in post-vaccination antibody titer.
|
Day 240
|
|
Percentage of Participants With HAI Titers Above Or Equal To Prespecified Thresholds At Day 240
Time Frame: Day 240
|
A serum HAI assay was used for measuring HA-specific antibodies against the A/H5N1/Indonesia/5/2005 influenza strain.
The prespecified antibody threshold levels were as follows: ≥1:10, ≥1:20, ≥1:40, ≥1:80, ≥1:160, and ≥1:320.
|
Day 240
|
|
Percentage of Participants With ELLA Titers Above Or Equal to Prespecified Thresholds At Day 240
Time Frame: Day 240
|
A serum ELLA assay was used for measuring NA-specific antibodies against the A/H5N1/Indonesia/5/2005 influenza strain.
The prespecified antibody threshold levels were as follows: ≥1:10, ≥1:20, ≥1:40, ≥1:80, ≥1:160, and ≥1:320.
|
Day 240
|
|
Geometric Mean Titer of Antibody Response Against HA Glycoprotein Measured By Microneutralization (MN) Assay
Time Frame: D1,29 Cohorts: Day 1, Day 29 (28 days post dose 1), Day 36 (7 days post dose 2), and Day 57 (28 days post dose 2), D1,57 Cohorts: Day 1, Day 57 (56 days post dose 1), Day 64 (7 days post dose 2), and Day 85 (28 days post dose 2)
|
Neutralizing antibody response to H5 hemagglutinin was measured by MN assay.
Antibody titers were expressed as Geometric Mean Titers.
|
D1,29 Cohorts: Day 1, Day 29 (28 days post dose 1), Day 36 (7 days post dose 2), and Day 57 (28 days post dose 2), D1,57 Cohorts: Day 1, Day 57 (56 days post dose 1), Day 64 (7 days post dose 2), and Day 85 (28 days post dose 2)
|
|
Geometric Mean Fold Rise of Antibody Response to HA Glycoprotein Measured By MN Assay
Time Frame: D1,29 Cohorts: Day 29 (28 days post dose 1), Day 36 (7 days post dose 2), and Day 57 (28 days post dose 2), D1,57 Cohorts: Day 57 (56 days post dose 1), Day 64 (7 days post dose 2), and Day 85 (28 days post dose 2)
|
Neutralizing antibody response to H5 hemagglutinin was measured by MN assay.
Geometric Mean Fold Rise was reported as a ratio to Day 1.
|
D1,29 Cohorts: Day 29 (28 days post dose 1), Day 36 (7 days post dose 2), and Day 57 (28 days post dose 2), D1,57 Cohorts: Day 57 (56 days post dose 1), Day 64 (7 days post dose 2), and Day 85 (28 days post dose 2)
|
|
Percentage of Participants With Seroconversion of Antibody Response to HA Glycoprotein Measured By MN Assay
Time Frame: D1,29 Cohorts: Day 29 (28 days post dose 1), Day 36 (7 days post dose 2), and Day 57 (28 days post dose 2), D1,57 Cohorts: Day 57 (56 days post dose 1), Day 64 (7 days post dose 2), and Day 85 (28 days post dose 2)
|
Neutralizing antibody response to H5 hemagglutinin was measured by MN assay.
Seroconversion was recorded if participant had pre-vaccination antibody titer < LLOQ and a post-vaccination antibody titer ≥ 4 x LLOQ, or a pre-vaccination antibody titer ≥LLOQ and a ≥4-fold increase in post-vaccination antibody titer.
|
D1,29 Cohorts: Day 29 (28 days post dose 1), Day 36 (7 days post dose 2), and Day 57 (28 days post dose 2), D1,57 Cohorts: Day 57 (56 days post dose 1), Day 64 (7 days post dose 2), and Day 85 (28 days post dose 2)
|
|
Percentage of Participants With MN Titers Above Or Equal To Prespecified Thresholds
Time Frame: D1,29 Cohorts: Day 57 (28 days post dose 2), D1,57 Cohorts: Day 85 (28 days post dose 2)
|
Neutralizing antibody response to H5 hemagglutinin was measured by MN assay.
The prespecified antibody threshold levels were as follows: ≥1:10, ≥1:20, ≥1:40, ≥1:80, ≥1:160, and ≥1:320.
|
D1,29 Cohorts: Day 57 (28 days post dose 2), D1,57 Cohorts: Day 85 (28 days post dose 2)
|
Collaborators and Investigators
This is where you will find people and organizations involved with this study.
Sponsor
Collaborators
Investigators
- Study Director: Clinical Program Director, Arcturus Therapeutics
Study record dates
These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.
Study Major Dates
Study Start (Actual)
December 10, 2024
Primary Completion (Actual)
June 13, 2025
Study Completion (Actual)
December 5, 2025
Study Registration Dates
First Submitted
September 16, 2024
First Submitted That Met QC Criteria
September 17, 2024
First Posted (Actual)
September 19, 2024
Study Record Updates
Last Update Posted (Actual)
September 4, 2026
Last Update Submitted That Met QC Criteria
August 12, 2026
Last Verified
August 1, 2026
More Information
Terms related to this study
Additional Relevant MeSH Terms
- Respiratory Tract Infections
- Infections
- Orthomyxoviridae Infections
- RNA Virus Infections
- Virus Diseases
- Respiratory Tract Diseases
- Influenza, Human
- Inorganic Chemicals
- Chlorine Compounds
- Biological Products
- Complex Mixtures
- Vaccines
- Sodium Compounds
- Viral Vaccines
- Chlorides
- Hydrochloric Acid
- Influenza Vaccines
- Sodium Chloride
Other Study ID Numbers
- ARCT-2304-01
Plan for Individual participant data (IPD)
Plan to Share Individual Participant Data (IPD)?
NO
IPD Plan Description
Individual participant data will only be made available to study investigators at this time.
Drug and device information, study documents
Studies a U.S. FDA-regulated drug product
Yes
Studies a U.S. FDA-regulated device product
No
product manufactured in and exported from the U.S.
No
This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.