NCT03598439

Randomized Influenza Vaccine Evaluation of Immune Response

Randomized Open-Label Trial to Compare Immunogenicity of Egg-Based and Non-Egg Based Quadrivalent Influenza Vaccines Among Adults 18-64 Years of Age (US Flu Vaccine Effectiveness Serologic Study, 2018-19 and 2019-20)

• Status: Completed
• Phase: Phase 4
• Study type: Interventional
• Enrollment: 366 (actual)
• Sponsor: Marshfield Clinic Research Foundation · Academic / Other
• Sex: All
• Age: 18 Years – 64 Years
• Healthy volunteers: Not accepted

Summary

Licensed influenza vaccines are manufactured with a variety of technologies. The majority are split, inactivated vaccines derived from egg-adapted, high growth reassortant viruses. Two US licensed products do not use egg-adapted viruses: Flucelvax (mammalian cell culture) and FluBlok (recombinant). There is increasing evidence that egg propagation induces virus mutations that impair the immune responses to circulating viruses. However, the impact of egg-propagation on clinical vaccine effectiveness is uncertain, and there is no preferential recommendation for any specific influenza vaccine product or technology. A direct comparison of serologic response to egg based and non-egg based vaccines in adults has not been performed. This randomized trial will compare serologic responses to the egg- and non-egg A(H3N2) vaccine component. The study cohort will be followed for two influenza seasons to evaluate sequential vaccination effects on immune response.

Conditions

• Influenza

Interventions

Type	Name	Description
BIOLOGICAL	Standard IIV4	Standard inactivated influenza vaccine
BIOLOGICAL	Recombinant	Influenza vaccine that uses a hemagglutinin protein manufactured in insect cells with a baculovirus vector
BIOLOGICAL	Cell-culture	inactivated influenza vaccine manufactured using mammalian cell lines; current vaccine uses a cell-propagated H3N2 strain.

Timeline

• Start date: 2018-07-30
• Primary completion: 2020-03-18
• Completion: 2024-07-09
• First posted: 2018-07-26
• Last updated: 2025-11-21

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated drug study