FDA Expands Indication for Flucelvax Quadrivalent to Children 6 Months and Older BY IDSE NEWS STAFF
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he FDA expanded the indication for a cell-based quadrivalent influenza vaccination (QIVc; Flucelvax Quadrivalent, Seqirus) for children as young as 6 months old. The expanded age indication is supported by a phase 3 clinical study demonstrating that ccIIV4 was as safe and immunogenic as a standard quadrivalent seasonal influenza vaccine (QIV) in children 6 months to younger than 4 years of age during the U.S. 2019-2020 influenza season, according to data presented at the Pediatric Academic Society (PAS) virtual annual meeting on May 1, 2021. This observer-blinded, controlled study randomized 2,414 U.S. children to receive QIVc or QIV. Participants received one or two vaccine doses 28 days apart, based on vaccination history, and were followed for at least 180 days. Noninferiority of QIVc to QIV was concluded if the upper bound of the two-sided 95% confidence interval for the postvaccination geometric mean titer (GMT) ratio did not exceed 1.5 and the seroconversion rate (SCR) difference did not exceed 10% for each of the four strains tested (A/H1N1, A/ H3N2, B/Yamagata and B/Victoria), which was reached. Safety profiles also were comparable between QIVc and QIV. The most common adverse events were similar between vaccinated groups, and included tenderness, erythema at the injection site, irritability and sleepiness. The vaccine is produced with a cell-based manufacturing process, an alternative to traditional egg-based manufacturing, which can cause the strain to mutate at several steps throughout the manufacturing process, and may lead to an antigenic mismatch between the circulating strains and the inactivated influenza strains contained within the seasonal influenza vaccine, according to the CDC. Cell-based influenza vaccines are designed to produce a better match to the World Health Organization selected influenza virus strains by avoiding egg-adapted changes, and therefore may be more effective, according to the CDC, and may offer additional advantages over the standard manufacturing process, including increased scalability and production speed in the event of an influenza pandemic. Children younger than 5 years old, particularly those younger than 24 months, are at increased risk for developing serious influenza-related complications, including pneumonia. According to the CDC, almost 50,000 hospitalizations occurred in children during the 2019-2020 U.S. influenza season, and there were more than 486 influenza-related deaths in this age group. The CDC recommends everyone 6 months of age and older
without contraindications receive an influenza vaccine annually. In related news, the FDA granted supplemental approval of a multidose vial of Influenza A(H5N1) Monovalent Vaccine, Adjuvanted (Audenz, Seqirus), the first adjuvanted, cell-based influenza vaccine designed to help protect people 6 months of age and older against influenza A(H5N1) in the event of a pandemic. The approval marks an important milestone in pandemic preparedness, the company said. “Producing Audenz in multidose vials allows for increased speed and efficiency, which is absolutely critical to help protect public health in the case of an influenza pandemic,” said Marc Lacey, the executive director of Pandemic Response Solutions at Seqirus. “According to the CDC, the influenza A(H5N1) virus is highly pathogenic and has high pandemic potential, so it’s critical to be prepared.”
Adjuvanted, Cell-Based Technology Audenz combines Seqirus’ proprietary MF59 adjuvant technology, designed to create broad, cross-reactive antibodies, with its cell-based manufacturing platform. This adjuvant is an important part of pandemic preparedness planning because it reduces the amount of antigen required to produce an immune response, increasing the number of doses of vaccine developed, so that a large number of people can be vaccinated as quickly as possible (Vaccine 2014;32:5027-5034). Under the terms of the public-private partnership with the Biomedical Advances Research and Development Authory, and the Department of Health and Human Services, established in 2009, Seqirus would deliver 150 million influenza vaccine doses to the U.S. government to support an influenza pan■ demic response within six months. The sources work for Seqirus.
INFECTIOUS DISEASE SPECIAL EDITION • WINTER 2021
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