Palivizumab coverage rates among moderate-to-late preterm infants in Korea: a nationwide cross-sectional study.

Objectives: Since October 2016, Korea has implemented a national reimbursement program for palivizumab aimed at moderate-to-late preterm (MLPT) infants born between 32 0/7 weels and 35 6/7 weeks of gestation during the respiratory syncytial virus (RSV) season (October-March). However, large-scale data on coverage rates and associated factors remain limited. This study evaluated palivizumab coverage rates and identified predictive factors influencing its administration in MLPT infants.

Methods: This nationwide, population-based cross-sectional study utilized data from the Korean National Health Insurance Service collected between October 2016 and March 2019. MLPT infants eligible for palivizumab reimbursement were divided into administration and non-administration groups. Seasonal and overall coverage rates were assessed. A multivariate logistic regression analysis examined factors associated with palivizumab administration, with a focus on infant and maternal characteristics.

Results: Among 2,843 eligible MLPT infants, 1,201 (42.2%) received palivizumab, while 1,642 (57.8%) did not. Although coverage rates increased annually, they remained suboptimal. Lower palivizumab prophylaxis coverage was observed in infants with higher gestational ages, female sex, absence of low birth weight, those born in March, residents of non-capital areas, infants not admitted to a neonatal intensive care unit at birth, and infants of mothers aged <35 years.

Conclusions: In the initial 3 RSV seasons following the introduction of palivizumab reimbursement for MLPT infants in Korea, the overall coverage rate was low (42.2%). National policies targeting infants with higher gestational ages, those born in March, and those residing in non-capital areas are necessary to improve coverage and ensure equitable RSV prophylaxis.