Randomized, double-blind comparison of standard-dose vs. high-dose trivalent inactivated influenza vaccine in...

Area of Science:

• Immunology
• Pediatric Transplant Medicine
• Vaccinology

Background:

• Children undergoing solid organ transplantation (SOT) exhibit diminished immune responses to vaccinations.
• Influenza vaccination is crucial for protecting immunocompromised pediatric populations.

Purpose of the Study:

• To evaluate the immunogenicity and safety of a high-dose (HD) versus standard-dose (SD) trivalent inactivated influenza vaccine (TIV) in pediatric SOT recipients.
• To compare immune responses and adverse events between HD-TIV and SD-TIV groups.

Main Methods:

• A randomized controlled trial involving 38 pediatric SOT recipients aged 3-17 years, at least six months post-transplant.
• Participants were randomized 2:1 to receive either HD-TIV (60 μg) or SD-TIV (15 μg).
• Immune responses (four-fold titer rise) and local/systemic reactions were assessed before and after vaccination.

Main Results:

• The HD-TIV group showed a higher percentage of four-fold titer rise to the H3N2 strain compared to the SD-TIV group.
• Mild, transient local and systemic reactions (tenderness, fatigue, body ache) were more frequent in the HD-TIV group but resolved within three days.
• No severe adverse events or transplant rejection were attributed to the vaccinations.

Conclusions:

• High-dose influenza vaccine (HD-TIV) was well-tolerated in pediatric SOT recipients.
• HD-TIV demonstrated potentially increased immunogenicity compared to SD-TIV, particularly against the H3N2 strain.
• Further investigation in a Phase 2 trial is warranted to confirm these findings.