ARCT-2303 / Arcturus Therap, CSL Behring - LARVOL DELTA

Immunogenicity and safety of self-amplifying mRNA COVID-19 vaccine (ARCT-2303), with or without co-administration of seasonal inactivated influenza vaccine in adults: a phase 3, randomised, controlled, observer-blind, multicentre study. (PubMed, EClinicalMedicine) - P3 | "Between March 27, 2024 and April 10, 2025, we performed a randomised, observer-blind, placebo-controlled, phase 3 study with 1499 adult participants to compare immune responses of sa-mRNA vaccine, encoding spike glycoprotein of the XBB.1.5 subvariant (ARCT-2303), with vaccine encoding the ancestral strain (ARCT-154), as measured by geometric mean titres of neutralising antibodies and SARS-CoV-2 neutralising antibody seroconversion rates against the Omicron XBB.1.5, and to assess the immunological non-inferiority of co-administered ARCT-2303 and influenza vaccines compared with separately administered vaccines, as measured by neutralising antibodies against Omicron XBB.1.5.6 and haemagglutinin inhibition against influenza vaccine strains. We conclude that ARCT-2303 induces a robust immune response against the vaccine variant of SARS-CoV-2 and can be co-administered with licenced influenza vaccines in adults with no impact on the safety or immunogenicity of either..."

Journal • P3 data • Infectious Disease • Influenza • Novel Coronavirus Disease • Respiratory Diseases

Immunogenicity and Safety Study of Self-amplifying MRNA COVID-19 Vaccine Administered with Influenza Vaccines in Adults (clinicaltrials.gov) - P3 | N=1499 | Completed | Sponsor: Arcturus Therapeutics, Inc. | Active, not recruiting ➔ Completed

Trial completion • Infectious Disease • Influenza • Novel Coronavirus Disease • Respiratory Diseases

Immunogenicity and Safety Study of Self-amplifying mRNA COVID-19 Vaccine Administered With Influenza Vaccines in Adults (clinicaltrials.gov) - P3 | N=1680 | Active, not recruiting | Sponsor: Arcturus Therapeutics, Inc. | Recruiting ➔ Active, not recruiting

Enrollment closed • Infectious Disease • Influenza • Novel Coronavirus Disease • Respiratory Diseases

Immunogenicity and Safety Study of Self-amplifying mRNA COVID-19 Vaccine Administered With Influenza Vaccines in Adults (clinicaltrials.gov) - P3 | N=1680 | Recruiting | Sponsor: Arcturus Therapeutics, Inc. | Not yet recruiting ➔ Recruiting

Enrollment open • Infectious Disease • Influenza • Novel Coronavirus Disease • Respiratory Diseases

Immunogenicity and Safety Study of Self-amplifying mRNA COVID-19 Vaccine Administered With Influenza Vaccines in Adults (clinicaltrials.gov) - P3 | N=1680 | Not yet recruiting | Sponsor: Arcturus Therapeutics, Inc.

New P3 trial • Infectious Disease • Influenza • Novel Coronavirus Disease • Respiratory Diseases