tetano
Editor, Senior Moderator
J Infect Chemother
. 2024 Jul 1:S1341-321X(24)00178-8.
doi: 10.1016/j.jiac.2024.06.023. Online ahead of print. The efficacy and safety of a quadrivalent live attenuated influenza nasal vaccine in Japanese children: a phase 3, randomized, placebo-controlled study
Tetsuo Nakayama[SUP] 1 [/SUP], Takuya Hayashi[SUP] 2 [/SUP], Kentaro Makino[SUP] 3 [/SUP], Keiji Oe[SUP] 4 [/SUP]
Affiliations
Background: Vaccination is the primary method of preventing influenza infection and complications in young children. We evaluated the efficacy and safety of a single dose of MEDI3250 (intranasal, quadrivalent, live attenuated influenza vaccine) in healthy Japanese children during the 2016/17 influenza season.
Methods: In this multicenter, randomized, double-blind, phase 3 study (jRCT2080223345), participants aged 2-18 years received MEDI3250 or placebo (2:1), stratified by age (2-6 years, 7-18 years). The primary and secondary endpoints were the incidence of confirmed symptomatic onset of influenza caused by a circulating wild-type strain or by a vaccine-matched strain, respectively. Safety outcomes included the incidence of adverse events (AEs) and vaccine-related AEs.
Results: Overall, 910 participants received MEDI3250 (n = 608) or placebo (n = 302). For the primary endpoint (regardless of the influenza subtype), the incidence of influenza onset was 25.5% (MEDI3250) and 35.9% (placebo); relative risk reduction, 28.8% (95% confidence interval, 12.5% to 42.0%). For the secondary endpoint (vaccine-matched strain), the incidence was 10.9% (MEDI3250) and 17.2% (placebo); relative risk reduction, 36.6% (95% confidence interval, 6.5% to 56.8%). Solicited AEs occurred in 67.6% (MEDI3250) and 63.6% (placebo). Most events were mild; nasal discharge was most common (59.2% [MEDI3250] and 52.6% [placebo]). Unsolicited AEs occurred in 36.0% (MEDI3250) and 33.1% (placebo). The most common unsolicited vaccine-related AE was diarrhea (2.3%, both groups).
Conclusions: MEDI3250 had a greater preventive effect against influenza onset in Japanese children than placebo; no new safety signals were observed relative to previous clinical and post-marketing studies of MEDI3250.
Keywords: Japan; intranasal vaccine; pediatric; seasonal influenza; vaccine efficacy; vaccine safety.
. 2024 Jul 1:S1341-321X(24)00178-8.
doi: 10.1016/j.jiac.2024.06.023. Online ahead of print. The efficacy and safety of a quadrivalent live attenuated influenza nasal vaccine in Japanese children: a phase 3, randomized, placebo-controlled study
Tetsuo Nakayama[SUP] 1 [/SUP], Takuya Hayashi[SUP] 2 [/SUP], Kentaro Makino[SUP] 3 [/SUP], Keiji Oe[SUP] 4 [/SUP]
Affiliations
- PMID: 38959995
- DOI: 10.1016/j.jiac.2024.06.023
Background: Vaccination is the primary method of preventing influenza infection and complications in young children. We evaluated the efficacy and safety of a single dose of MEDI3250 (intranasal, quadrivalent, live attenuated influenza vaccine) in healthy Japanese children during the 2016/17 influenza season.
Methods: In this multicenter, randomized, double-blind, phase 3 study (jRCT2080223345), participants aged 2-18 years received MEDI3250 or placebo (2:1), stratified by age (2-6 years, 7-18 years). The primary and secondary endpoints were the incidence of confirmed symptomatic onset of influenza caused by a circulating wild-type strain or by a vaccine-matched strain, respectively. Safety outcomes included the incidence of adverse events (AEs) and vaccine-related AEs.
Results: Overall, 910 participants received MEDI3250 (n = 608) or placebo (n = 302). For the primary endpoint (regardless of the influenza subtype), the incidence of influenza onset was 25.5% (MEDI3250) and 35.9% (placebo); relative risk reduction, 28.8% (95% confidence interval, 12.5% to 42.0%). For the secondary endpoint (vaccine-matched strain), the incidence was 10.9% (MEDI3250) and 17.2% (placebo); relative risk reduction, 36.6% (95% confidence interval, 6.5% to 56.8%). Solicited AEs occurred in 67.6% (MEDI3250) and 63.6% (placebo). Most events were mild; nasal discharge was most common (59.2% [MEDI3250] and 52.6% [placebo]). Unsolicited AEs occurred in 36.0% (MEDI3250) and 33.1% (placebo). The most common unsolicited vaccine-related AE was diarrhea (2.3%, both groups).
Conclusions: MEDI3250 had a greater preventive effect against influenza onset in Japanese children than placebo; no new safety signals were observed relative to previous clinical and post-marketing studies of MEDI3250.
Keywords: Japan; intranasal vaccine; pediatric; seasonal influenza; vaccine efficacy; vaccine safety.