NCT06279871Phase 3Completed

Immunogenicity and Safety Study of Self-amplifying mRNA COVID-19 Vaccine Administered With Influenza Vaccines in 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 completion2024-10-09Actual

Enrollment · participants1514Actual

Source updated2025-12-12Last update listed in the registry record

Version history

Changes to this trial

Last 12 months

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Posted 2025-12-12 · 1 field changed

Actual enrollment increased by 15 participants

− Before

~~1499 participants (actual)~~

+ After

1514 participants (actual)

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Posted 2025-11-13 · 1 field changed

Actual enrollment decreased by 15 participants

− Before

~~1514 participants (actual)~~

+ After

1499 participants (actual)

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Posted 2025-10-21 · 1 field changed

Main study measure wording changed

Text changed; whether the study measures changed has not been verified. Saved text may be shortened.

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− Before

Measure: SARS-CoV-2 ~~neutralizing~~ ~~antibody~~ ~~titers~~ Measure: ~~SARS-CoV-2~~ ~~neutralizing~~ ~~antibody~~ ~~seroconversion~~ ~~rates Measure:~~ Hemagglutination Inhibition (HI) ~~titers~~ Measure: SARS-CoV-2 ~~neutralizing~~ ~~antibody~~ ~~titers~~

+ After

Measure: Groups 2a and 2b and ARCT-154-J01 Historical Control: Geometric Mean Titers (GMT) of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Neutralizing Antibody Titers Against Omicron XBB.1.5 Subvariant at Day 29 Measure: Groups 2a and 2b and ARCT-154-J01 Historical Control: Number of Participants With Seroconversion to SARS-CoV-2 Neutralizing Antibody Against Omicron XBB.1.5 Subvariant at Day 29 Measure: Groups 1a and 3a: Adjusted Hemagglutination Inhibition (HI) GMTs Against Influenza Vaccine Strains at Day 29 Measure: Groups 1a and 2a: Adjusted GMTs of SARS-CoV-2 Neutralizing Antibody Against Omicron XBB.1.5 Subvariant at Day 29

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Study details

Conditions studied

COVID-19

Treatments or interventions studied

ARCT-2303Biological
Influenza vaccineBiological
Influenza vaccine, adjuvantedBiological

Primary outcomes · main study measures

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measure: Groups 2a and 2b and ARCT-154-J01 Historical Control: Geometric Mean Titers (GMT) of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Neutralizing Antibody Titers Against Omicron XBB.1.5 Subvariant at Day 29; timeFrame: Day 29; measure: Groups 2a and 2b and ARCT-154-J01 Historical Control: Number of Participants With Seroconversion to SARS-CoV-2 Neutralizing Antibody Against Omicron XBB.1.5 Subvariant at Day 29; description: Seroconversion was defined as either a pre-vaccination titer below the lower limit of quantitation (LLOQ) and a postvaccination titer ≥4xLLOQ; or a pre-vaccination titer ≥LLOQ and a ≥4-fold increase in post-vaccination titer.; timeFrame: Day 29; measure: Groups 1a and 3a: Adjusted Hemagglutination Inhibition (HI) GMTs Against Influenza Vaccine Strains at Day 29; description: Influenza vaccine strains were A/H1N1, A/H3N2, B/Victoria, and B/Yamagata.; timeFrame: Day 29; measure: Groups 1a and 2a: Adjusted GMTs of SARS-CoV-2 Neutralizing Antibody Against Omicron XBB.1.5 Subvariant at Day 29; timeFrame: Day 29

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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