NCT04668339Phase 2Terminated

A Trial Evaluating the Safety and Effects of an RNA Vaccine ARCT-021 in Healthy Adults

Study sponsor: Arcturus Therapeutics, Inc.

Compare the available registry edits below. Primary completion is the date data collection ends for the main study measures; it does not tell you when results will be published.

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Primary completion2022-03-01Actual

Enrollment · participants581Actual

Source updated2025-05-15Last update listed in the registry record

Version history

Changes to this trial

Last 12 months

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Study details

Conditions studied

Covid19; SARS-CoV Infection; Corona Virus Infection

Treatments or interventions studied

ARCT-021 single dose primingBiological
ARCT-021 two lower dose primingBiological
ARCT-021 two higher dose primingBiological
Placebo (two doses), primingBiological
Randomized boosterBiological
Placebo boosterBiological

Primary outcomes · main study measures

Read the study measures

measure: Percentage of Participants Reporting Solicited Local Adverse Events Within 7 Days Post Each Priming Vaccination; description: Per prespecified analysis, solicited local adverse events were defined as pain, erythema, swelling, or injection site tenderness. Solicited adverse reactions were recorded by the participant in an eDiary. Per prespecified analysis, solicited adverse events were not evaluated for severity (such as, serious or non-serious). A summary of all unsolicited adverse events and solicited adverse events regardless of causality is located in the Reported Adverse Events module.; timeFrame: For 7 days following each dose administration (Day 0 up to Day 7 for Vaccination 1 and Day 29 up to Day 35 for Vaccination 2); measure: Percentage of Participants Reporting Solicited Local Adverse Events Within 7 Days Post Booster Vaccination; description: Per prespecified analysis, solicited local adverse events were defined as pain, erythema, swelling, or injection site tenderness. Solicited adverse reactions were recorded by the participant in an eDiary. Per prespecified analysis, solicited adverse events were not evaluated for severity (such as, serious or non-serious). A summary of all unsolicited adverse events and solicited adverse events regardless of causality is located in the Reported Adverse Events module.; timeFrame: For 7 days following each dose administration (Day 208 up to Day 215); measure: Percentage of Participants Reporting Solicited Systemic Adverse Events Within 7 Days Post Each Priming Vaccination; description: Per prespecified analysis, solicited systemic adverse events were defined as fever, headache, fatigue, myalgia, arthralgia, nausea, chills, diarrhea, dizziness, and vomiting. Per prespecified analysis, solicited adverse events were not evaluated for severity (such as, serious or non-serious). A summary of all unsolicited adverse events and solicited adverse events regardless of causality is located in the Reported Adverse Events module.; timeFrame: For 7 days following each dose administration (Day 0 up to Day 7 for Vaccination 1 and Day 29 up to Day 35 for Vaccination 2); measure: Percentage of Participants Reporting Solicited Systemic Adverse Events Within 7 Days Post Booster Vaccination; description: Per prespecified analysis, solicited systemic adverse events were defined as fever, headache, fatigue, myalgia, arthralgia, nausea, chills, diarrhea, dizziness, and vomiting. Per prespecified analysis, solicited adverse events were not evaluated for severity (such as, serious or non-serious). A summary of all unsolicited adverse events and solicited adverse events regardless of causality is located in the Reported Adverse Events module.; timeFrame: For 7 days post booster dose administration (Day 208 up to Day 215); measure: Percentage of Participants Reporting Unsolicited Adverse Events Up to 28 Days Post Each Priming Vaccination; description: An unsolicited AE was defined as any AE (serious and nonserious) occurring after administration of first dose of study vaccine and before the end of study. A summary of all unsolicited adverse events and solicited adverse events regardless of causality is located in the Reported Adverse Events module.; timeFrame: 28 days following each dose administration (Day 0 up to Day 28 for Vaccination 1 and Day 29 up to Day 56 for Vaccination 2); measure: Percentage of Participants Reporting Unsolicited Adverse Events Up to 28 Days Post Booster Vaccination; description: An unsolicited AE was defined as any AE (serious and nonserious) occurring after administration of first dose of study vaccine and before the end of study. A summary of all unsolicited adverse events and solicited adverse events regardless of causality is located in the Reported Adverse Events module.; timeFrame: 28 days following each dose administration (Day 208 up to 236 days); measure: Percentage of Participants Reporting Treatment-Emergent Serious Adverse Events (SAE), Medically Attended Adverse Events (MAAE) and New Onset of Chronic Disease (NOCD) Post Each Priming Vaccination; description: SAEs were defined as any event that resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in a persistent or significant incapacity or substantial disruption of the ability to conduct normal life functions, resulted in a congenital anomaly or birth defect, or was an important medical event. An NOCD was defined as any AE that led to the new diagnosis of a chronic medical condition that was not present or suspected prior to enrollment. An MAAE was an AE that led to an unscheduled visit (including a telemedicine visit) to a healthcare practitioner. A summary of all unsolicited adverse events and solicited adverse events regardless of causality is located in the Reported Adverse Events module.; timeFrame: Up to Day 207; measure: Percentage of Participants Reporting Treatment-emergent Serious Adverse Events, Medically Attended Adverse Events and New Onset of Chronic Disease Post Booster Vaccination; description: SAEs were defined as any event that resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in a persistent or significant incapacity or substantial disruption of the ability to conduct normal life functions, resulted in a congenital anomaly or birth defect, or was an important medical event. An NOCD was defined as an AE that led to the new diagnosis of a chronic medical condition that was not present or suspected prior to enrollment. An MAAE was an AE that led to an unscheduled visit (including a telemedicine visit) to a healthcare practitioner. A summary of all unsolicited adverse events and solicited adverse events regardless of causality is located in the Reported Adverse Events module.; timeFrame: Day 208 to early termination (up to 396 days); measure: Geometric Mean Titer (GMT) of Serum Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Neutralizing Antibodies Post Priming Vaccination; timeFrame: Day 1; measure: GMT of SARS-CoV-2 Neutralizing Antibodies Post Priming Vaccination; timeFrame: Day 56; measure: GMT of SARS-CoV-2 Neutralizing Antibodies Post Booster Vaccination; timeFrame: Day 208; measure: GMT of SARS-CoV-2 Neutralizing Antibodies Post Booster Vaccination; timeFrame: Day 236; measure: Geometric Mean Fold Rise (GMFR) in SARS-CoV-2 Neutralizing Antibody Titers Post Priming Vaccination; description: GMFR is reported as a ratio to baseline (Day 0).; timeFrame: Day 56; measure: Geometric Mean Fold Rise (GMFR) in SARS-CoV-2 Neutralizing Antibody Titers Post Booster Vaccination; description: GMFR is reported as a ratio to baseline (Day 0).; timeFrame: Day 208; measure: GMFR in SARS-CoV-2 Neutralizing Antibody Titers Post Booster Vaccination; description: GMFR is reported as a ratio to baseline (Day 0).; timeFrame: Day 236; measure: Percentages of Participants Achieving Greater Than or Equal to 2-fold and 4-fold Increase From Before Vaccination (Baseline) in SARS-CoV-2 Serum Neutralizing Antibody Levels at Day 56; timeFrame: Baseline up to Day 56; measure: Percentages of Participants Achieving Greater Than or Equal to 2-fold and 4-fold Increase From Before Vaccination (Baseline) in SARS-CoV-2 Serum Neutralizing Antibody Levels at Day 208; timeFrame: Baseline up to Day 208; measure: Percentages of Participants Achieving Greater Than or Equal to 2-fold and 4-fold Increase From Before Vaccination (Baseline) in SARS-CoV-2 Serum Neutralizing Antibody Levels at Day 236; timeFrame: Baseline up to Day 236

History coverage

Research sample: selected versions from May 2023 onward plus a preceding baseline where available. Only selected fields were retained; endpoint measures were truncated to 300 characters. This is not complete trial or sponsor history. Daily snapshots begin when collection starts.

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