Respiratory Syncytial Virus Hospitalizations among U.S. Preterm Infants Compared with Term Infants Before and After the 2014 American Academy of Pediatrics Guidance on Immunoprophylaxis: 2012-2016

Episodic Cost of Lower Respiratory Tract Illness due to Respiratory Syncytial Virus Among US Infants During the First Year of Life

A study of 2 health care claims databases (commercial, Medicaid) was undertaken to estimate the episodic cost of lower respiratory tract illness due to respiratory syncytial virus among infants aged <12 months overall, by age, and by birth gestational age. Among commercial-insured infants, mean costs were $28 812 for hospitalized episodes, $2575 for emergency department episodes, and $336 for outpatient clinic episodes. Costs were highest among infants aged <1 month and infants with a gestational age ≤32 weeks and were comparable among Medicaid-insured infants, albeit somewhat lower. The cost of lower respiratory tract illness due to respiratory syncytial virus during the acute phase of illness is high, especially among the youngest infants and those born premature.

Economic Burden of Medically Attended Respiratory Syncytial Virus Infections Among Privately Insured Children Under 5 Years of Age in the USA

BACKGROUND

The cost of medically attended RSV LRI (lower respiratory infection) is critical in determining the economic value of new RSV immunoprophylaxes. However, most studies have focused on intermittent RSV encounters, not the episode of care that captures the entirety of RSV illness.

METHODS

We created age- and condition-specific cohorts of children under 5 years of age using MarketScan® data (2015-2019). We contrasted aggregating healthcare costs over RSV-LRTI episodes to ascertaining costs based on RSV-specific encounters only. Economic burden was estimated by multiplying costs per encounter or per episode by their respective incidence rates.

RESULTS

Average cost was higher per episode than per encounter regardless of settings (inpatient: $28,586 vs. $18,056 and outpatient/ED: $2099 vs. $407 for infants). Across ages, the economic burden was highest for infants and RSV-LRTI requiring inpatient care, but the burden in outpatient/ED settings was disproportionately higher than costs due to higher incidence rates (for inpatient vs. outpatient episodes: $226,403 vs. $101,269; for inpatient vs. outpatient encounters: $151,878 vs. $38,819 per 1000 infant-years). For high-risk children, cost and burden were up to 3-10 times higher, respectively.

CONCLUSIONS

With a comprehensive stratification by settings and risk condition, the encounter- versus episode-based estimates provide a robust range for policymakers' economic appraisal of new RSV immunoprophylaxes.

Model correction of diagnostic coding-based RSV incidence for children 0-4 years in the US

BACKGROUND

Although administrative claims data have a high degree of completeness, not all medically attended Respiratory Syncytial Virus-associated lower respiratory tract infections (RSV-LRTIs) are tested or coded for their causative agent. We sought to determine the attribution of RSV to LRTI in claims data via modeling of temporal changes in LRTI rates against surveillance data.

METHODS

We estimated the weekly incidence of LRTI (inpatient, outpatient, and total) for children 0-4 years using 2011-2019 commercial insurance claims, stratified by HHS region, matched to the corresponding weekly NREVSS RSV and influenza positivity data for each region, and modelled against RSV, influenza positivity rates, and harmonic functions of time assuming negative binomial distribution. LRTI events attributable to RSV were estimated as predicted events from the full model minus predicted events with RSV positivity rate set to 0.

RESULTS

Approximately 42% of predicted RSV cases were coded in claims data. Across all regions, the percentage of LRTI attributable to RSV were 15-43%, 10-31%, and 10-31% of inpatient, outpatient, and combined settings, respectively. However, when compared to coded inpatient RSV-LRTI, 9 of 10 regions had improbable corrected inpatient LRTI estimates (predicted RSV/coded RSV ratio < 1). Sensitivity analysis based on separate models for PCR and antigen-based positivity showed similar results.

CONCLUSIONS

Underestimation based on coding in claims data may be addressed by NREVSS-based adjustment of claims-based RSV incidence. However, where setting-specific positivity rates is unavailable, we recommend modeling across settings to mirror NREVSS's positivity rates which are similarly aggregated, to avoid inaccurate adjustments.

Effectiveness and Safety of Palivizumab for the Prevention of Serious Lower Respiratory Tract Infection Caused by Respiratory Syncytial Virus: A Systematic Review

OBJECTIVE

Palivizumab is a humanized monoclonal antibody approved for the prevention of serious lower respiratory tract infection (LRTI) caused by respiratory syncytial virus (RSV) in infants and young children at high risk of RSV disease. This systematic review summarized evidence on the effectiveness and safety of palivizumab when used in approved populations.

STUDY DESIGN

A systematic review of Phase III trials and observational studies was conducted according to the population, intervention, comparator, outcome, timing, setting (PICOTS) approach (PROSPERO, CRD42021281380). Target populations consisted of infants with a history of premature birth (≤35-week gestational age) and children aged <2 years with bronchopulmonary dysplasia (BPD) or with hemodynamically significant congenital heart disease (hs-CHD). Outcomes of interest included RSV-related hospitalization, admission to intensive care unit (ICU), requirement for mechanical ventilation, treatment-related adverse events (AEs), and RSV-related deaths. Information sources were literature search (Ovid MEDLINE and Embase), pragmatic searches, and snowballing (covering the period up to 07 September 2021).

RESULTS

A total of 60 sources were included (5 Phase III trials and 55 observational studies). RSV-related hospitalization rates following palivizumab prophylaxis in Phase III trials were 1.8% in premature infants and 7.9% in children with BPD, which were significantly lower than rates in placebo arms. In the real-world setting, similar hospitalization rates were found (0.7-4.0% in premature infants [16 studies] and 0-5.5% in patients with BPD [10 studies]) with ICU admission reported in 0 to 33.3% of patients hospitalized for RSV. In Phase III trials, RSV-related mortality rates were 0.2 and 0.3%, while AEs occurred in 11% of premature and/or BPD patients and 7.2% of hs-CHD patients, consisting mainly of injection site reaction, fever, and diarrhea. Similar results were found in observational studies.

CONCLUSION

This systematic review supports the effectiveness and safety of palivizumab in the indicated populations.

KEY POINTS

· Systematic review supports the positive benefit-risk profile of palivizumab in the indicated populations.. · Real-world safety and effectiveness of palivizumab are consistent with Phase III trials results.. · Palivizumab reduces RSV-related hospitalizations, ICU admissions, and need for mechanical ventilation..

Cost Savings Without Increased Risk of Respiratory Hospitalization for Preterm Children after the 2014 Palivizumab Policy Update

OBJECTIVES

Our objective was to compare rates of hospitalizations for respiratory illnesses in preterm and full-term (FT) children for 4 years before and after the 2014 update to the American Academy of Pediatrics (AAP) respiratory syncytial virus (RSV) immunoprophylaxis guidance, which restricted eligibility among infants born at 29 to 34 weeks in the first winter and all preterm infants in the second winter after neonatal discharge.

STUDY DESIGN

We conducted pre-post and interrupted time series analyses on claims data from a commercial national managed care plan. We compared the number of RSV and all respiratory hospital admissions in the first and second RSV seasons after neonatal discharge among a cohort of preterm children, regardless of palivizumab status, in the 4 years before and after the implementation of the 2014 palivizumab eligibility change. A FT group was included for reference.

RESULTS

The cohort included 821 early preterm (EP, <29 weeks), 4,790 moderate preterm (MP, 29-34 weeks), and 130,782 FT children. Palivizumab use after the policy update decreased among MP children in the first and second RSV seasons after neonatal discharge, without any change in the odds of hospitalization with RSV or respiratory illness. For the EP group, there was no change in the rate of palivizumab or the odds of hospitalization with RSV or respiratory illness after the policy update. For the FT group, there was a slight decrease in odds of hospitalization post-2014 after the policy update. The interrupted time series did not reveal any secular trends over time in hospitalization rates among preterm children. Following the policy change, there were cost savings for MP children in the first and second RSV seasons, when accounting for the cost of hospitalizations and the cost of palivizumab.

CONCLUSION

Hospitalizations for RSV or respiratory illness did not increase, and cost savings were obtained after the implementation of the 2014 AAP palivizumab prophylaxis policy.

KEY POINTS

· Palivizumab use decreased among children born moderate preterm (29 to34 weeks) after the 2014 palivizuamb policy update.. · There was no change in odds of hospitalization with respiratory syncitial virus or respiratory illness among preterm infants after the policy update when compared to before.. · There were cost savings, when accounting for the cost of hospitalizations and the cost of palivizumab, after the policy update among children born moderate preterm..

Increasing Rates of RSV Hospitalization among Preterm Infants: A Decade of Data

OBJECTIVE

In 2014, the American Academy of Pediatrics (AAP) changed its policy on the use of respiratory syncytial virus immunoprophylaxis (RSV-IP) so that RSV-IP was no longer recommended for use among infants without other medical conditions born >29 weeks of gestational age (wGA). This study examines 10-year trends in RSV-IP and RSV hospitalizations among term infants and preterm infants born at 29 to 34 wGA, including the 5 RSV seasons before and 5 RSV seasons after the AAP guidance change.

STUDY DESIGN

A retrospective observational cohort study of a convenience sample of infants less than 6 months of age during RSV season (November-March) born between July 1, 2008, and June 30, 2019, who were born at 29 to 34 wGA (preterm) or >37 wGA (term) in the IBM MarketScan Commercial and Multi-State Medicaid databases. We excluded infants with medical conditions that would independently qualify them for RSV-IP. We identified RSV-IP utilization along with RSV and all-cause bronchiolitis hospitalizations during each RSV season. A difference-in-difference model was used to determine if there was a significant change in the relative rate of RSV hospitalizations following the 2014 policy change.

RESULTS

There were 53,535 commercially insured and 85,099 Medicaid-insured qualifying preterm infants and 1,111,670 commercially insured and 1,492,943 Medicaid-insured qualifying term infants. Following the 2014 policy change, RSV-IP utilization decreased for all infants, while hospitalization rates tended to increase for preterm infants. Rate ratios comparing preterm to term infants also increased. The relative rate for RSV hospitalization for infants born at 29 to 34 wGA increased significantly for both commercially and Medicaid-insured infants (1.95, 95% CI: 1.67-2.27, p <0.001; 1.70, 95% CI: 1.55-1.86, p <0.001, respectively). Findings were similar for all-cause bronchiolitis hospitalizations.

CONCLUSION

We found that the previously identified increase in RSV hospitalization rates among infants born at 29 to 34 wGA persisted for at least 5 years following the policy change.

KEY POINTS

· Immunoprophylaxis rates decreased after the 2014 American Academy of Pediatrics guidelines update.. · Rate of RSV hospitalization increased among preterm infants after the 2014 AAP guidelines update.. · Increase in RSV hospitalization persisted for at least 5 years after AAP guidelines update..

Risk of RSV-related hospitalization is associated with gestational age in preterm (born at 29-34 wGA) infants without outpatient palivizumab administration

Palivizumab has been shown to decrease RSV-related hospitalization (RSVH) risk and reduce RSVH severity. American Academy of Pediatrics (AAP) guidance on administration of palivizumab has changed over time; in 2014, palivizumab was no longer recommended in preterm infants born at 29 weeks gestational age (wGA) or later. This study's objective was to describe RSVH risk and severity in preterm infants (29-34 wGA) without comorbidities relative to healthy term infants and to each other by gestational age. Using the MarketScan Multi-State Medicaid and Commercial Databases, infants born from July 1, 2014 to June 30, 2019, at 29-34 wGA (preterm) and >37 wGA (term) were identified. During RSV seasons (November to March) from 2014 to 2020, claims incurred by infants while they were <6 months old were evaluated for RSVH and RSVH characteristics. This study included 63,351 preterm infants and 1,076,389 term infants without outpatient palivizumab administration. Rate of RSVH was higher in infants with lower wGA at birth and ranged 3.32-5.72 per 100 infant-seasons in Medicaid-insured infants and 3.21-4.84 in commercially insured infants. Relative risk of RSVH was 5-8 times higher in Medicaid-insured preterm infants and 3-5 times higher in commercially insured preterm infants compared to term infants. ICU admissions and mechanical ventilation were more common during RSVH in preterm infants relative to term infants. RSV-related outpatient healthcare utilization was also 2-3 times higher in preterm infants born at 31-34 wGA. Increased utilization of palivizumab among infants born at 29-34 wGA may decrease RSVH rates and result in less severe course in preterm infants with RSVH.

Real-World Studies of Respiratory Syncytial Virus Hospitalizations among Moderate/Late Preterm Infants Exposed to Passive Immunoprophylaxis with Palivizumab

This article aims to assess the real-world effectiveness of palivizumab immunoprophylaxis against respiratory syncytial virus (RSV)-associated hospitalization (RSVH) rates in otherwise healthy moderate/late preterm infants and discuss the role of palivizumab in preventing acute and long-term outcomes. We identified studies in the PubMed and Embase databases that reported patient-level data on (1) exposure to palivizumab in preterm infants born between 29 and 35 weeks of gestational age (or subsets within this range) ≤ 2 years of chronological age, and (2) the outcome of RSVH. Six studies assessed RSVH in infants this gestational age who had been exposed or not to palivizumab and reported patient-level data. Exposure was associated with a reduction in RSVH rates that was comparable to the reduction seen in controlled clinical trials (weighed mean 4.0-fold reduction). RSV immunoprophylaxis in preterm infants within 29 to 35 weeks of gestational age is associated with a considerably lower burden of RSVH. KEY POINTS: · RSV is the leading cause of lower respiratory tract infection hospitalization in infants.. · Palivizumab prevents RSVH in a real-world scenario.. · Immunoprophylaxis should be used in high-risk infants..

RSV-related hospitalization and outpatient palivizumab use in very preterm (born at <29 wGA) infants: 2003-2020

Respiratory syncytial virus (RSV) is a leading cause of bronchiolitis and pneumonia in children under one year and a leading cause of infant hospitalization. Palivizumab was approved by the FDA in 1998 as RSV immunoprophylaxis to prevent severe RSV disease in children with specific health conditions and those born at <35 weeks gestational age (wGA). This study compared RSV-related hospitalization (RSVH) and RSVH characteristics in very preterm (<29 wGA) and term (>37 wGA) infants. Using the MarketScan Commercial and Multi-State Medicaid administrative claims databases, infants born between 7/1/2003 and 6/30/2020 were identified and classified as very preterm or term. Infants with evidence of health conditions, such as congenital heart disease and cystic fibrosis, were excluded. During 2003-2020 RSV seasons (November to March), claims incurred by infants while they were <12 months old were evaluated for outpatient administration of palivizumab and RSVH. The study included 40,123 very preterm infants and 4,421,942 term infants. Rate of RSVH in very preterm infants ranged 1.5-3.8 per 100 infant-seasons in commercially insured infants and 3.5-8.4 in Medicaid insured infants and were inversely related to wGA at birth. Relative risk of RSVH in very preterm was 3-4 times higher, and ICU admissions and mechanical ventilation were more common during RSVH in very preterm infants relative to term infants. However, these outcomes were less common or less severe in very preterm infants who received outpatient palivizumab administration, despite evidence of higher baseline risk of RSVH in these infants.

OUP accepted manuscript

Background

Limited data are available on the economic costs of respiratory syncytial virus (RSV) infections among infants and young children in the United States.

Methods

We performed a systematic literature review of 10 key databases to identify studies published between 1 January 2014 and 2 August 2021 that reported RSV-related costs in US children aged 0–59 months. Costs were extracted and a systematic analysis was performed.

Results

Seventeen studies were included. Although an RSV hospitalization (RSVH) of an extremely premature infant costs 5.6 times that of a full-term infant ($10 214), full-term infants accounted for 82% of RSVHs and 70% of RSVH costs. Medicaid-insured infants were 91% more likely than commercially insured infants to be hospitalized for RSV treatment in their first year of life. Medicaid financed 61% of infant RSVHs. Paying 32% less per hospitalization than commercial insurance, Medicaid paid 51% of infant RSVH costs. Infants’ RSV treatment costs $709.6 million annually, representing $187 per overall birth and $227 per publicly funded birth.

Conclusions

Public sources pay for more than half of infants’ RSV medical costs, constituting the highest rate of RSVHs and the highest expenditure per birth. Full-term infants are the predominant source of infant RSVHs and costs.

Palivizumab for preventing severe respiratory syncytial virus (RSV) infection in children

BACKGROUND

Respiratory viruses are the leading cause of lower respiratory tract infection (LRTI) and hospitalisation in infants and young children. Respiratory syncytial virus (RSV) is the main infectious agent in this population. Palivizumab is administered intramuscularly every month during five months in the first RSV season to prevent serious RSV LRTI in children. Given its high cost, it is essential to know if palivizumab continues to be effective in preventing severe RSV disease in children.

OBJECTIVES

To assess the effects of palivizumab for preventing severe RSV infection in children.

SEARCH METHODS

We searched CENTRAL, MEDLINE, three other databases and two trials registers to 14 October 2021, together with reference checking, citation searching and contact with study authors to identify additional studies. We searched Embase to October 2020, as we did not have access to this database for 2021.

SELECTION CRITERIA

We included randomised controlled trials (RCTs), including cluster-RCTs, comparing palivizumab given at a dose of 15 mg/kg once a month (maximum five doses) with placebo, no intervention or standard care in children 0 to 24 months of age from both genders, regardless of RSV infection history.  DATA COLLECTION AND ANALYSIS: We used Cochrane's Screen4Me workflow to help assess the search results. Two review authors screened studies for selection, assessed risk of bias and extracted data. We used standard Cochrane methods. We used GRADE to assess the certainty of the evidence. The primary outcomes were hospitalisation due to RSV infection, all-cause mortality and adverse events. Secondary outcomes were hospitalisation due to respiratory-related illness, length of hospital stay, RSV infection, number of wheezing days, days of supplemental oxygen, intensive care unit length of stay and mechanical ventilation days.

MAIN RESULTS

We included five studies with  a total of 3343 participants. All studies were parallel RCTs, assessing the effects of 15 mg/kg of palivizumab every month up to five months compared to placebo or no intervention in an outpatient setting, although one study also included hospitalised infants. Most of the included studies were conducted in children with a high risk of RSV infection due to comorbidities like bronchopulmonary dysplasia and congenital heart disease. The risk of bias of outcomes across all studies was similar and predominately low.  Palivizumab reduces hospitalisation due to RSV infection at two years' follow-up (risk ratio (RR) 0.44, 95% confidence interval (CI) 0.30 to 0.64; 5 studies, 3343 participants; high certainty evidence). Based on 98 hospitalisations per 1000 participants in the placebo group, this corresponds to 43 (29 to 62) per 1000 participants in the palivizumab group. Palivizumab probably results in little to no difference in mortality at two years' follow-up (RR 0.69, 95% CI 0.42 to 1.15; 5 studies, 3343 participants; moderate certainty evidence). Based on 23 deaths per 1000 participants in the placebo group, this corresponds to 16 (10 to 27) per 1000 participants in the palivizumab group. Palivizumab probably results in little to no difference in adverse events at 150 days' follow-up (RR 1.09, 95% CI 0.85 to 1.39; 3 studies, 2831 participants; moderate certainty evidence). Based on 84 cases per 1000 participants in the placebo group, this corresponds to 91 (71 to 117) per 1000 participants in the palivizumab group. Palivizumab probably results in a slight reduction in hospitalisation due to respiratory-related illness at two years' follow-up (RR 0.78, 95% CI 0.62 to 0.97; 5 studies, 3343 participants; moderate certainty evidence). Palivizumab may result in a large reduction in RSV infection at two years' follow-up (RR 0.33, 95% CI 0.20 to 0.55; 3 studies, 554 participants; low certainty evidence). Based on 195 cases of RSV infection per 1000 participants in the placebo group, this corresponds to 64 (39 to 107) per 1000 participants in the palivizumab group. Palivizumab also reduces the number of wheezing days at one year's follow-up (RR 0.39, 95% CI 0.35 to 0.44; 1 study, 429 participants; high certainty evidence).

AUTHORS' CONCLUSIONS

The available evidence suggests that prophylaxis with palivizumab reduces hospitalisation due to RSV infection and results in little to no difference in mortality or adverse events. Moreover, palivizumab results in a slight reduction in hospitalisation due to respiratory-related illness and may result in a large reduction in RSV infections. Palivizumab also reduces the number of wheezing days. These results may be applicable to children with a high risk of RSV infection due to comorbidities. Further research is needed to establish the effect of palivizumab on children with other comorbidities known as risk factors for severe RSV disease (e.g. immune deficiencies) and other social determinants of the disease, including children living in low- and middle-income countries, tropical regions, children lacking breastfeeding, living in poverty, or members of families in overcrowded situations.

Unintended Consequences Following the 2014 American Academy of Pediatrics Policy Change for Palivizumab Prophylaxis among Infants Born at Less than 29 Weeks' Gestation

OBJECTIVE

The aim of this study is to compare outpatient respiratory syncytial virus (RSV) immunoprophylaxis (IP) use and relative RSV hospitalization (RSVH) rates for infants <29 weeks' gestational age (wGA) versus term infants before and after the 2014 American Academy of Pediatrics (AAP) policy change.

STUDY DESIGN

Infants were identified in the MarketScan Commercial and Multi-State Medicaid databases. Outpatient RSV IP receipt and relative <29 wGA/term hospitalization risks in 2012 to 2014 and 2014 to 2016 were assessed using rate ratios and a difference-in-difference model.

RESULTS

Outpatient RSV IP receipt by infants <29 wGA and aged <3 months in the Commercial and Medicaid populations and those aged 3 to <6 months in the Medicaid population declined after 2014. Relative RSVH risks for infants <29 wGA were numerically greater after 2014, with infants aged <3 months and Medicaid infants experiencing the greatest increases. Difference-in-difference results indicated a significantly increased relative risk of RSVH for infants <29 wGA versus term (both cohorts aged 0 to <6 months) in the Medicaid-insured population (1.68, p = 0.0054). A nonsignificant increase of similar magnitude occurred in the commercially insured population (1.57, p = 0.2867).

CONCLUSION

The 2014 policy change was associated with a decrease in RSV IP use and an increase in RSVH risk among otherwise healthy infants <29 wGA.

A Comparison of Respiratory Syncytial Viral Prophylaxis in Multiple Births versus Singletons in the Canadian Registry of Palivizumab

OBJECTIVE

The aim of this study is to compare respiratory illness-related hospitalization (RIH) and respiratory syncytial virus (RSV)-related hospitalization (RSVH) in multiple births versus singletons, who received palivizumab during the RSV season and participated in the Canadian registry of palivizumab (CARESS).

STUDY DESIGN

Prospective, observational study of infants aged <2 years recruited across 32 centers over 12 RSV seasons from 2005 to 2017. Demographic data were collected at enrolment and RIH events were recorded monthly.

RESULTS

A total of 25,003 infants were enrolled of whom 6,949 (27.8%) were of multiple birth, and 18,054 (72.2%) were singletons. A significantly larger proportion of the multiple births were premature (80.2%) compared with the singleton group (56.8%). Multiples had a lower gestational age (mean ± standard deviation): 31.2 ± 3.2 versus 33.2 ± 5.5 weeks and birth weight (mean: 1,590 ± 606.8 vs. 2,069.4 ± 1068.5 g; both p < 0.0005). They were younger at enrolment (4.5 ± 5.0 vs. 6.1 ± 6.8 months), and fewer attended daycare (1.9 vs. 4.6%), and experienced exposure to smoking (24.5 vs. 29.9%), but more lived in a crowded household (36.7 vs. 19.4%); all p < 0.0005. Multiples had a longer length of neonatal stay (51.1 ± 65.9 vs. 47.9 ± 67.8 days), and more required respiratory support (65.7 vs. 57.7%), but for shorter duration (22.6 ± 32.9 vs. 24.7 ± 40.6 days); all p < 0.001. RIH and RSVH rates (%) in multiples versus singletons were 4.7; 7.7 and 1.4; and 1.6, respectively. Cox regression showed that multiples had a lower risk of RIH compared with singletons (hazard ratio [HR] = 0.616, 95% confidence interval [CI]: 0.543-0.698, p < 0.0005), but not RSVH (HR: 0.77, 95% CI: 0.57-1.02, p = 0.071).

CONCLUSION

Multiple birth infants, who are known to be at greater risk for severe RSVH compared with singletons, are well protected by palivizumab, provided adherence to the monthly injection scheme is guaranteed.

Update on respiratory syncytial virus hospitalizations among U.S. preterm and term infants before and after the 2014 American Academy of Pediatrics policy on immunoprophylaxis: 2011-2017

Palivizumab is the only licensed respiratory syncytial virus (RSV) immunoprophylaxis (IP) available to prevent severe RSV disease in high-risk pediatric populations, including infants born at 29-34 weeks' gestational age (wGA). In 2014, the American Academy of Pediatrics (AAP) stopped recommending RSV IP use for otherwise healthy 29-34 wGA infants and stated that 29-34 wGA infants and term infants have similar RSV hospitalization (RSVH) rates. This study aimed to compare RSV IP use and RSVH rates in 29-34 wGA infants and term infants during the 3 RSV seasons before and after the 2014 AAP policy change. RSV IP use in otherwise healthy infants 29-30, 31-32, and 33-34 wGA was estimated from pharmacy or outpatient medical claims for palivizumab. RSVH rates in the first 6 months of life were calculated per 100 infant-seasons. RSVH rate ratios were used to compare preterm infants and term infants before and after the policy change. Across infant cohorts (29-34 wGA) and chronologic age groups (<3 months and 3-<6 months), absolute decreases in RSV IP use between the combined 2011-2014 seasons and 2014-2017 seasons ranged from 7% to 38% and from 68% to 97%, respectively. Compared with 2011-2014, the RSVH risk increased 2.09-fold (P< .001) and 1.76-fold (P< .001) in 2014-2017 for infants born at 29-34 wGA and aged <6 months with commercial and Medicaid insurance, respectively. Overall, RSV IP use declined in the RSV seasons following the 2014 RSV IP policy change, and RSVH increased among 29-34 wGA infants aged <6 months.

The Future of Respiratory Syncytial Virus Disease Prevention and Treatment

Respiratory syncytial virus (RSV) is a major cause of respiratory tract infections in infants, young children, and older or immunocompromised adults. Although aerosolized ribavirin was licensed for RSV treatment on the basis of data demonstrating a reduced need for supplemental oxygen, ribavirin use is limited because of issues with efficacy, safety, and cost. Currently, the treatment of RSV is primarily supportive. New antiviral treatments for RSV are in the early stages of development, but it will be years until any of these may be licensed by the US Food and Drug Administration (FDA). Palivizumab, an RSV monoclonal antibody [immunoprophylaxis (IP)], has demonstrated effectiveness in disease prevention and is the only licensed IP for RSV disease in specific high-risk pediatric populations. Although its efficacy is well established, some challenges that may interfere with its clinical use include cost, need for monthly injections, and changing policy for use by the American Academy of Pediatrics (AAP). Preventing RSV disease would be possible through RSV vaccine development (e.g., live-attenuated, vector-based subunit, or particle-based). Alternatively, new long-acting monoclonal antibodies have demonstrated promising results in early clinical trials. Despite scientific advances, until new agents become available, palivizumab should continue to be used to reduce RSV disease burden in high-risk patients for whom it is indicated.

Severity and Cost of RSV Hospitalization Among US Preterm Infants Following the 2014 American Academy of Pediatrics Policy Change

The American Academy of Pediatrics (AAP) Committee on Infectious Diseases (COID) periodically publishes recommendations for respiratory syncytial virus (RSV) immunoprophylaxis (IP) use in pediatric patients considered to be at highest risk for severe RSV infection. In 2014, for the first time, the AAP COID stopped recommending the use of RSV IP for otherwise healthy infants born at 29 weeks’ gestational age (wGA) or later, stating that RSV hospitalization (RSVH) rates in this population are similar to those of term infants. Subsequently, epidemiological studies in the US at national and regional levels provided evidence of the impact of the policy change in 29–34 wGA infants. The results of these studies demonstrated a significant decrease in IP use after 2014 that was associated with an increased rate of RSVH in 29–34 wGA infants and an increase in morbidities. RSVH-related morbidities included pediatric intensive care unit (ICU) admissions, an increased need for mechanical ventilation, and an increase in the length of stay. After the change in recommendations, the costs of RSVH also rose among 29–34 wGA infants. The severity of the illness and expenses associated with RSVH were generally higher among 29–34 wGA infants of younger chronologic age compared with older preterm infants. Overall, these studies underscore that 29–34 wGA infants continue to be a high-risk pediatric population that could benefit from the protection provided by RSV IP. On the basis of these data, in 2018, the National Perinatal Association developed guidelines that recommended RSV IP for all ≤ 32 wGA infants and 32–35 wGA infants with additional risk factors. Re-evaluation of the AAP COID policy is warranted in light of these observations.

Impact of the 2014 American Academy of Pediatrics Policy on RSV Hospitalization in Preterm Infants in the United States

Despite being a leading cause of hospitalization due to lower respiratory tract infections, the treatment of respiratory syncytial virus (RSV) infection is primarily supportive. Palivizumab is the only licensed immunoprophylaxis (IP) available for preventing severe RSV infection in high-risk populations including ≤ 35 weeks' gestational age (wGA) infants and children with chronic lung disease of prematurity or congenital heart disease. The American Academy of Pediatrics (AAP) has published its IP recommendations since the approval of palivizumab. In 2014, the AAP stopped recommending RSV IP in 29-34 wGA infants without comorbidities and stated that RSV hospitalization (RSVH) risk in otherwise healthy ≥ 29 wGA infants and term infants was similar. Since then, experts in the field have debated the appropriateness of the 2014 policy change, and several real-world evidence studies at the national and regional levels in the US have examined the impact of the AAP policy on 29-34 wGA infants. Overall, these studies showed a significant decline in RSV IP use and a concurrent increase in RSVH risk among 29-34 wGA infants relative to term infants in the seasons after the 2014 policy change. A similar decrease in IP use and increase in RSVH risk was also observed among < 29 wGA infants relative to term infants after the 2014 policy change. This decrease could be an unintended consequence as < 29 wGA infants are an in-policy population recommended to receive RSV IP. According to the National Perinatal Association, strong evidence exists to support the use of RSV IP in all ≤ 32 wGA and 32-35 wGA infants with risk factors such as attending day care, having ≥ 1 school-aged siblings, twin or greater multiple gestation, younger age, and exposure to parental smoking. Until new preventive and treatment options become available, palivizumab can help prevent and mitigate RSV disease burden among high-risk preterm infants.

Respiratory Syncytial Virus Disease: Immunoprophylaxis Policy Review and Public Health Concerns in Preterm and Young Infants

Globally, respiratory syncytial virus (RSV) is a leading cause of hospitalization due to severe respiratory infections in infants of all gestational ages and children aged 5 years and younger, and it is associated with a substantial health care burden. Approximately, 1% to 3% of infants younger than 1 year are hospitalized with severe RSV disease in the United States. With no specific treatment or vaccine, palivizumab is the only licensed immunoprophylaxis for the prevention of severe RSV disease in high-risk pediatric populations, including infants born at or before 35 weeks' gestational age (wGA). In the United States, the American Academy of Pediatrics (AAP) periodically publishes its recommendation for the use of RSV immunoprophylaxis, which is largely followed by health care professionals and payers. In 2014, the AAP Committee on Infectious Diseases stopped recommending RSV immunoprophylaxis for otherwise healthy infants born at or after 29 wGA and stated that the RSV hospitalization rates in infants 29 to 34 wGA and full-term infants were similar. Several studies have demonstrated that a significant decline in palivizumab use following the AAP 2014 recommendations was accompanied by increases in rates of RSV hospitalization and disease severity and hospital costs in infants 29 to 34 wGA versus full-term infants. Despite the growing evidence demonstrating high RSV morbidity in infants 29 to 34 wGA, the AAP reaffirmed its 2014 policy in 2019. This article will discuss the critical roles and strategies of advocacy groups and nurses in providing the maximum protection with RSV immunoprophylaxis to all high-risk and label-eligible preterm infants.

A Survey of Parental Knowledge of Respiratory Syncytial Virus and Other Respiratory Infections in Preterm Infants

PURPOSE

Evaluate parental knowledge of respiratory syncytial virus (RSV) and other respiratory infections in preterm infants.

DESIGN

Survey.

SAMPLE

Five hundred and eighty-three parents of preterm infants with generalized, Canadian provincial representation.

MAIN OUTCOME

Knowledge of RSV infection, sources of information, and parental understanding of disease risk.

RESULTS

97.9 percent (571/583) of the parents had heard about RSV, since they all had a preterm infant. Sixty-one percent reported having good knowledge of RSV; 19.4 percent had very good knowledge; 19.7 percent had little or no awareness of RSV-related infection. Most (86.3 percent) believed that RSV illness was a very serious condition; 13 percent recognized that it could be a major problem for their child. Principal sources of information were the nurse, doctor and pamphlets. Over 480 participants cited 3 or more sources of additional information-Internet, social media platforms, and educational sessions. Respiratory syncytial virus prophylaxis was a priority, but knowledge regarding the eligibility criteria for prophylaxis is essential.

Updated cost-effectiveness analysis of palivizumab (Synagis) for the prophylaxis of respiratory syncytial virus in infant populations in the UK

AIMS

Respiratory syncytial virus (RSV) is a common cause of respiratory infection in infants and severe infection can result in hospitalization. The passive immunization, palivizumab, is used as prophylaxis against RSV, however, use in the UK is restricted to populations at high risk of hospitalization. This study assesses the cost-effectiveness (CE) of palivizumab in premature infants with and without risk factors for hospitalization (congenital heart disease [CHD], bronchopulmonary dysplasia [BPD]).

METHODS

A decision tree model, based on earlier CE analyses, was updated using data derived from targeted literature reviews and advice gained from a Round Table meeting. All costs were updated to 2019 prices. One-way and probabilistic sensitivity analyses were performed to assess the degree of uncertainty surrounding the results.

RESULTS

Palivizumab is dominant (i.e. clinically superior and cost saving) when used in premature infants born ≤35 weeks gestational age (wGA) without CHD or BPD and aged <6 months at the start of the RSV season, infants aged <24 months with CHD and infants aged <24 months requiring treatment for BPD within the last 6 months.

LIMITATIONS

One-way sensitivity analysis suggests that these results are highly sensitive to the efficacy of prophylaxis, number of doses, impact of long-term respiratory sequalae, rate of hospitalization and mortality due to RSV. A conservative approach has been taken toward long-term respiratory sequalae due to uncertainty around epidemiology and etiology and a lack of recent cost and utility data.

CONCLUSIONS

Palivizumab prophylaxis is cost-effective in preventing severe RSV infection requiring hospital admission in a wider population than currently recommended in UK guidelines. Prophylaxis in premature infants born <29 wGA, 29-32 wGA and 33-35 wGA without CHD or BPD aged <6 months at the start of the RSV season is not funded under current guidance, however, prophylaxis has been demonstrated to be cost-effective in this analysis.

Respiratory syncytial virus hospitalizations in US preterm infants after the 2014 change in immunoprophylaxis guidance by the American Academy of Pediatrics

Palivizumab is the only licensed and effective immunoprophylaxis (IP) available to prevent respiratory syncytial virus (RSV) infection in high-risk infants including infants born at ≤35 weeks' gestational age (wGA). In 2014, the American Academy of Pediatrics stopped recommending IP for otherwise healthy 29-34 wGA infants, stating that their risk of RSV hospitalization (RSVH) was similar to term infants. Recent studies have demonstrated a significant decline in IP use after 2014 that was accompanied by an increased risk of RSVH in 29-34 wGA infants vs term infants. Severity and healthcare utilization of RSVH were high among 29-34 wGA infants. In 2018, the National Perinatal Association developed guidelines advocating IP use in all ≤32 wGA infants and 32-35 wGA infants with additional risk factors. Risk factor predictive models can identify infants who are at risk for RSVH and promote cost-effective use of palivizumab until new methods of RSV prevention become available.

Respiratory Syncytial Virus and All-Cause Bronchiolitis Hospitalizations Among Preterm Infants Using the Pediatric Health Information System (PHIS)

Background

In 2014, the American Academy of Pediatrics stopped recommending palivizumab to otherwise healthy 29–34 weeks’ gestational age (wGA) infants aged <12 months at respiratory syncytial virus (RSV) season start. Here, we compare the burden of RSV hospitalizations (RSVH) and all-cause bronchiolitis hospitalizations (BH) before and after 2014 among otherwise healthy 29–34 wGA infants hospitalized at ≤6 months of age.

Methods

A historical, observational cohort study was conducted to evaluate RSVH and BH in 29–34 wGA infants during the 2010–2017 RSV seasons using encounter data from 51 United States children’s hospitals that comprise the Pediatric Health Information System.

Results

The overall cohort included 67 570 RSVH out of 96 281 patients with BH. wGA was known for 22 937 RSVH and 33 289 BH. For 29–34 wGA infants, there were 8.7% and 14.2% RSVH before and after 2014, respectively (P < .0001). Intensive care unit admissions increased for RSVH (from 54.5% to 64.2%; P = .0002) and BH (from 46.7% to 54.5%; P = .0005) after controlling for sex, race, comorbidity, and cluster. The total cost of care increased for RSVH from $37 million to nearly $60 million.

Conclusions

RSVH, BH, and their severity increased among 29–34 wGA infants in the 3 RSV seasons following 2014.

Healthcare resource utilization and costs in the 12 months following hospitalization for respiratory syncytial virus or unspecified bronchiolitis among infants

Aims: To examine healthcare resource utilization (HRU) and costs within 12 months after hospitalization for respiratory syncytial virus (RSVH) or unspecified bronchiolitis (UBH) in infants.Materials and methods: Infants born July 1, 2009-June 30, 2015 were identified in the MarketScan Medicaid and Commercial databases and were assigned to one of three cohorts: RSVH (with/without UBH), UBH, or comparator (no RSVH or UBH). Each infant was identified as pre-term (5 groups) or term (2 groups) based on weeks gestational age (wGA). Index dates were the first admission dates for RSVH or UBH infants and were randomly assigned to comparator infants based on time from birth to index in the RSVH cohort. HRU, all-cause costs, and incremental cost differences between hospitalized and comparator infants were assessed over 12 months post-index with and without the index hospitalization. Results were propensity score weighted to balance pre-index characteristics across hospitalization cohorts.Results: This study identified 15,872 RSVH infants, 6,081 UBH infants, and 986,087 comparator infants in the Medicaid population and 5,755 RSVH infants, 1,888 UBH infants, and 696,302 comparator infants in the commercial population. HRU in follow-up was greater for RSVH and UBH infants relative to comparator infants in both populations, including hospitalizations (commercial: 7.4%, 11.0%, 1.7%; Medicaid: 12.3%, 15.3%, 3.2%) and emergency department visits (commercial: 33.0%, 33.3%, 17.2%; Medicaid: 65.8%, 68.5%, 51.4%). HRU was highest among RSVH and UBH infants born at <29 wGA. Hospitalized infants had numerically higher follow-up costs than comparator infants, with incremental differences reaching $19,896 among Medicaid UBH infants and $37,417 among commercial RSVH infants.Limitations: RSV/UB may be miscoded in claims data.Conclusions: Infants hospitalized for RSV or UB largely had greater subsequent HRU and costs in the first year after index hospitalization than comparator infants. Absolute and incremental follow-up costs relative to comparator infants were highest among infants <29 wGA.