CSL Seqirus Announces Results of Pragmatic Study Comparing Adjuvanted and High-Dose Influenza Vaccines

Strategic Insights -

A recent study conducted by CSL Seqirus in collaboration with a large health system has provided valuable insights into the effectiveness of adjuvanted and high-dose influenza vaccines in preventing lab-confirmed influenza among adults 65 years of age and older. The study, presented at the IDWeek 2024 conference, found that adjuvanted and high-dose influenza vaccines did not differ in effectiveness, with a relative vaccine effectiveness (rVE) of 1.5% between the two vaccines. This aligns with previous research and the current U.S. Centers for Disease Control and Prevention's (CDC) Advisory Committee on Immunization Practices (ACIP) recommendation.

Key Takeaways:

  • The study, conducted in collaboration with a large health system, compared the effectiveness of adjuvanted and high-dose influenza vaccines in preventing lab-confirmed influenza among adults 65 years of age and older.
  • The results of the first season of the study found that adjuvanted and high-dose influenza vaccines did not differ in effectiveness, with a relative vaccine effectiveness (rVE) of 1.5% between the two vaccines.
  • There was no difference in effectiveness between adjuvanted and high-dose influenza vaccines for the prevention of hospitalization or emergency department visits for PCR-confirmed influenza, and hospitalization for all-cause community-acquired pneumonia.
  • The findings of the study align with previous research based on diagnostic and test confirmed outcomes, systematic reviews, and meta-analyses, which have shown comparable effectiveness between adjuvanted and high-dose influenza vaccines.
  • The study is being conducted as a two-season pragmatic randomized study with approximately 480,000 individuals 65 years of age and older anticipated each season throughout facilities within a large health system.
  • The association director, Ian McGovern, highlights the commitment of CSL Seqirus to generating high-quality real-world evidence data (RWE) through this study.

Statistics:

  • Relative vaccine effectiveness (rVE) of adjuvanted influenza vaccine vs high-dose inactivated influenza vaccine (HD-IIV) was 1.5% (95% confidence interval: -8.4 to 10.5) among adults 65 years of age and older.
  • Approximately 480,000 individuals 65 years of age and older are anticipated to be studied each season throughout facilities within a large health system.
  • The study is a collaborative effort between CSL Seqirus and a large health system.
  • The second season and pooled season analyses will be performed following the end of the 2024-2025 season.

Sources:

  • CSL Seqirus news release
  • IDWeek 2024 conference presentation
  • U.S. Centers for Disease Control and Prevention's (CDC) Advisory Committee on Immunization Practices (ACIP) recommendation