Cell-Based Influenza Vaccines Show 19.8% Superior Effectiveness Over Egg-Based Vaccines in Real-World Study
核心洞察
Cell-based quadrivalent influenza (搜索) vaccines demonstrated 19.8% greater relative vaccine effectiveness compared to egg-based vaccines in preventing test-confirmed influenza during the 2023-2024 season.
The superiority was consistent across all patient subgroups, including pediatric (6 months to 17 years), adult (18 to 64 years), outpatient, and high-risk populations.
This marks the fifth consecutive season showing cell-based vaccine superiority and provides the first evidence of effectiveness in children as young as 6 months old.
Cell-based influenza (搜索) vaccines demonstrated significantly superior effectiveness compared to traditional egg-based vaccines across all patient populations during the 2023-2024 influenza season, according to new real-world evidence presented at IDWeek. The comprehensive study found that cell-based quadrivalent influenza vaccines (QIVc) provided 19.8% greater relative vaccine effectiveness in preventing test-confirmed influenza compared to egg-based quadrivalent vaccines (QIVe (搜索)).
Study Design and Population
Researchers from CSL Seqirus (搜索) conducted a retrospective test-negative design study using linked data from electronic health records, medical and pharmacy claims, and laboratory tests. The analysis included 106,779 vaccinated patients aged 6 months to 64 years who received either cell-based or egg-based influenza (搜索) vaccines and were tested for influenza within 7 days of developing acute respiratory or febrile illness (搜索).
"Evaluating the clinical benefit of cell-based vaccines compared to standard egg-based vaccines using real-world data was prompted by interest in investigating if the egg-adapted mutations that can come from the use of standard egg-based vaccines can potentially affect vaccine effectiveness," explained Alicia N. Stein, PhD, MBiostat, director of real world evidence at CSL Seqirus (搜索).
Consistent Results Across Patient Groups
The study revealed that QIVc was "significantly more effective" than QIVe (搜索) in preventing test-confirmed influenza (搜索), with an adjusted relative vaccine effectiveness (rVE) of 19.8% (95% CI, 15.7-23.8%) in the full population. Among the QIVc group, 2,119 patients (12.6%) were test-positive cases and 14,750 (87.4%) were test-negative controls, while the QIVe group had 14,559 (16.2%) cases and 75,351 (83.8%) controls.
The effectiveness advantage remained consistent across all assessed subpopulations. In pediatric patients (6 months to 17 years), the adjusted rVE was 19.6% (95% CI, 13.6-25.3%), while adults (18 to 64 years) showed an adjusted rVE of 18.5% (95% CI, 12.1-24.5%). The outpatient subgroup demonstrated an rVE of 19.7% (95% CI, 15.3-23.8), and the high-risk subgroup showed 14.7% (95% CI, 8.7-20.3) relative effectiveness.
Clinical Significance and Historical Context
This study represents the fifth consecutive season of extensive retrospective test-negative studies demonstrating greater protection from cell-based influenza (搜索) vaccines compared to standard egg-based vaccines. Notably, it provides the first evidence of superiority in pediatric populations from 6 months of age, a group that has only been included in cell-based influenza vaccine indications since October 2021.
"The estimated rVE would have translated to a substantial public heath impact across pediatric and adult populations," Stein concluded. "Real-world evidence allows for a more comprehensive understanding of a vaccine's impact, supporting better health outcomes and informed decision-making."
Manufacturing Implications
The superior effectiveness of cell-based vaccines addresses concerns about egg-adapted mutations that can occur during the production of standard egg-based vaccines. While many influenza (搜索) vaccines are traditionally produced in hens' eggs, the cell-based manufacturing process may preserve the antigenic properties of circulating influenza viruses more effectively.
"This study adds a fifth season to the ongoing exploration of comparative vaccine effectiveness across seasons with different characteristics of circulating and vaccine viruses," Stein noted, highlighting the growing body of evidence supporting cell-based vaccine technology in influenza (搜索) prevention.