Association of RSV-related hospitalization and non-compliance with Palivizumab among commercially insured infants: a retrospective claims analysis

Abstract

BackgroundPalivizumab has been shown to decrease the incidence of hospitalization due to respiratory syncytial virus (RSV) in infants at risk of severe RSV disease. We examined the association between compliance with palivizumab dosing throughout the RSV season and risk of RSV-related hospitalization in clinical practice.MethodsSubjects who were born and discharged from the hospital before the RSV season and received ≥1 palivizumab dose during their first RSV season were identified from a large US commercial health insurance database between 01/01/03 and 12/31/09. Subjects were deemed compliant if they received ≥5 palivizumab doses without gaps (>35 days) and their first dose was received by November 30. RSV-related hospitalizations were identified using ICD-9-CM diagnosis codes and examined over 2 observation periods: post-index dose and RSV season. A Cox proportional hazard model was used to evaluate the association between non-compliance and RSV-related hospitalization.ResultsOf the 5,003 subjects who received palivizumab, 62% were deemed non-compliant. Non-compliant subjects had significantly higher unadjusted rates of RSV-related hospitalizations compared to compliant subjects during both observation periods (post-index: 6.1 vs. 2.8 per 100 infant seasons, p < 0.001; RSV season: 5.9% vs. 2.3%; p < 0.001). In multivariate analyses, non-compliance was significantly associated with higher risk of RSV-related hospitalization (HR = 2.01; p < 0.001). Of the 225 RSV-related hospitalizations observed during the RSV season, 61 (27%) occurred before the first dose of palivizumab.ConclusionsSubjects who did not receive monthly dosing of palivizumab throughout the RSV season had significantly higher rates of RSV-related hospitalizations. The RSV-related hospitalizations prior to the first dose of palivizumab suggest some dosing was started too late.

Rationale for full-season dosing for passive antibody prophylaxis of respiratory syncytial virus

“…These results were also observed in 2 recent retrospective cohort studies evaluating outcomes in insurance claims databases during the 6 RSV seasons between 2003–2004 and 2008–2009 24 , 25 …”

RSV Hospitalizations in Comparison With Regional RSV Activity and Inpatient Palivizumab Administration, 2010–2013

“…One study conversely found that RSV hospitalizations were more frequent before the initiation of palivizumab dosing (including outpatient dosing) for the season. 20 This may be a product of a difference in inpatient and outpatient patterns of palivizumab initiation or that the population of children' s hospitals studied in PHIS may not be representative of the overall population. While we do not know when outpatient palivizumab dosing began in relationship to our study, it is possible that inpatient providers (compared with those in the outpatient setting) are more familiar with RSV hospitalization patterns and use these patterns when dosing palivizumab to inpatients.…”

“…[16][17][18] Although there is no RSV vaccine, certain children at high risk are given prophylaxis with palivizumab, an RSV monoclonal immunoglobulin, which can reduce RSV hospitalizations. 19,20 The latest policy statement from the American Academy of Pediatrics (AAP) recommends that palivizumab administration for these children at high risk begins at the start of regional activity season. 21 One study found that using RSV regional activity data to determine when to initiate prophylaxis rather than using a set initiation date (November) would increase protection by 15%.…”

“…It is possible that some children may benefit from palivizumab before the start of RSV regional activity season. One study using a national health insurance database noted that 27% of RSV hospitalizations occurred before the first dose of palivizumab was administered at the start of the regional activity season, 20 although this study only assessed privately insured patients who had received at least 1 dose of palivizumab and did not address regional differences in RSV activity and hospitalizations. Light et al 22 found that ∼10% of RSV hospitalizations occurred outside of the regional activity season at the state level in Florida.…”

Viral load in respiratory syncytial virus infected premature newborns under prophylaxis with palivizumab

“…Several studies showed that the Palivizumab® does not just prevent HRSV infection but also decreases the hospitalization occurrence [12], and in fact, only one of our study group was hospitalized. Despite the recognized importance of Palivizumab® prophylaxis, in our study 17.4% of children were infected by HRSV.…”