A Phase 1/2 Trial Evaluating the Safety and Immunogenicity of an mRNA-based Seasonal Influenza Vaccine Candidate Encoding Hemagglutinin and Neuraminidase.
Ilse De Coster, Jose F Cardona, Murdo Ferguson, Isabel Leroux-Roels, Haylene Nell, Stefano Berrè, Sonia Schoonbroodt, Clarisse Lorin, Leroy Jide Ovbude, Brian Moldt
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引用次数: 0
Abstract
Introduction: Hemagglutinin (HA) is the principal immunologic target of most licensed seasonal influenza vaccines. Targeting both HA and neuraminidase (NA) might improve vaccine effectiveness. This randomized phase 1/2 study evaluated an investigational mRNA-based quadrivalent seasonal influenza vaccine, encoding HA and NA of A/H1N1, A/H3N2, B/Victoria, and B/Yamagata (FLUm4HA-4NA).
Methods: In phase 1, adults aged 18-50 years received either one of twelve mRNA vaccine formulations of varying HA-only or HA and NA mRNA doses, or a licensed quadrivalent seasonal influenza comparator. In phase 2, participants aged 18-64 years (younger adults) and 65-85 years (older adults) received FLUm4HA-4NA (three groups per age category, with different HA/NA mRNA doses) or age-appropriate licensed quadrivalent comparator. Primary endpoints were safety/reactogenicity, and hemagglutination inhibition [HI] and NA inhibition [NI] responses against the four seasonal strains at day 29. Cross-reactive HI/NI responses against drifted strains, virus neutralization, and HA-/NA-specific cell-mediated immunity were evaluated in phase 2 as tertiary objectives.
Results: A total of 293 participants (21-25 per group) were vaccinated in phase 1, 480 younger (108-137 per group) and 483 older adults (117-125 per group) in phase 2. Solicited events were more frequent with FLUm4HA-4NA than comparators and were mostly short-lived and mild or moderate. No deaths or vaccine-related serious adverse events were reported. Post-vaccination HI and neutralizing titers in the FLUm4HA-4NA groups were similar or higher for the A strains and lower for the B strains versus comparators. NI responses exceeded those of comparators for all four strains. HI and NI titers against evaluated drifted A strains were similar or higher after FLUm4HA-4NA than after comparator vaccination. HA-specific CD4+ and CD8+ T-cell responses were generally higher after FLUm4HA-4NA than comparator vaccination.
Conclusions: FLUm4HA-4NA showed an acceptable safety profile and humoral and cellular immunogenicity in the study population, supporting further development and formulation optimization to improve influenza B HI responses.
期刊介绍:
Infectious Diseases and Therapy is an international, open access, peer-reviewed, rapid publication journal dedicated to the publication of high-quality clinical (all phases), observational, real-world, and health outcomes research around the discovery, development, and use of infectious disease therapies and interventions, including vaccines and devices. Studies relating to diagnostic products and diagnosis, pharmacoeconomics, public health, epidemiology, quality of life, and patient care, management, and education are also encouraged.
Areas of focus include, but are not limited to, bacterial and fungal infections, viral infections (including HIV/AIDS and hepatitis), parasitological diseases, tuberculosis and other mycobacterial diseases, vaccinations and other interventions, and drug-resistance, chronic infections, epidemiology and tropical, emergent, pediatric, dermal and sexually-transmitted diseases.