Baloxavir Marboxil Prescription and Subsequent Medical Resource Use
among School-Aged Children
Abstract
Background: Baloxavir marboxil is a novel class of antiviral agent for
influenza, introduced into clinical practice in 2018. A concern remains
about the variant virus with reduced susceptibility after baloxavir
exposure and its clinical consequences including healthcare seeking
behavior. Methods: Using a healthcare database in Japan, we compared the
medical resource use following baloxavir and neuraminidase inhibitors
(NAIs) treatment among children aged 7- 15 years. Study period was from
December 2018 to March 2019. The primary endpoint was the composite of
hospitalization, laboratory and radiological tests, and antibiotic use
over 1-9 days of antiviral treatment. As prespecified exploratory
analyses, secondary outcomes were assessed and subgroup analyses
comparing baloxavir with each NAI were done. Results: Data from 115 867
prescriptions in 115 238 children were analyzed (median age: 10 years,
risk of severe influenza in 26%, baloxavir accounting for 43%).
Overall, baloxavir use did not increase the subsequent medical resource
utilization in the composite endpoint (adjusted odds ratio [aOR]:
1.002; 95% confidence interval [CI]: 0.999–1.005; P= .16), as were
likelihoods of other secondary outcomes. In the subgroup analysis,
baloxavir use was associated with higher medical resource use than
oseltamivir (aOR: 1.011; 95% CI: 1.007–1.015; P < .001) and
lower resource use than zanamivir (aOR: 0.995; 95% CI 0.991–0.999; P=
.039). Conclusions: Prescribing baloxavir rather than NAIs did not
increase medical resource utilization within 9 days of treatment, except
in one exploratory comparison with oseltamivir. Our data were derived
from single-year observation in one country, thereby requiring future
researches.