Respiratory Syncytial Virus Immune Globulin Research Articles

Cost Effectiveness of Respiratory Syncytial Virus Prophylaxis

Respiratory syncytial virus (RSV) is the leading cause of infant hospitalization in the US. The economic burden of severe disease is substantial, including hospitalization costs and out-of-pocket expenses. RSV prophylaxis with either RSV immune globulin intravenous (RSV-IGIV) or palivizumab has been shown to be effective in reducing RSV-related hospitalizations. Motavizumab, a new enhanced-potency humanized RSV monoclonal antibody, is presently in clinical trials. RSV-IGIV and palivizumab are associated with high acquisition costs. Cost-effectiveness analyses are therefore of great importance in helping to determine who should receive RSV prophylaxis. Six studies have analysed the cost effectiveness of RSV-IGIV, 14 have analysed the cost effectiveness of palivizumab and five have analysed the cost effectiveness of both agents, two of which directly compared palivizumab with RSV-IGIV. The cost effectiveness of motavizumab has not been studied. Significant variation exists in the modelling used in these analyses. Many studies have examined short-term benefits such as reducing hospitalizations and associated costs, while fewer studies have examined long-term benefits such as QALYs or life-years gained. The payer and society have been the most common perspectives used. The endpoints examined varied and generally did not account for the potential impact of RSV prophylaxis on RSV-related complications such as asthma. While some studies have reported acceptable cost-effectiveness ratios for RSV prophylaxis, the majority failed to show cost savings or cost-effectiveness ratios below commonly accepted thresholds for either RSV-IGIV or palivizumab. Cost effectiveness of RSV prophylaxis tended to be more favourable in populations with specific risk factors, including premature infants < or =32 weeks' gestational age, and infants or children aged < 2 years with chronic lung disease or congenital heart disease. Comparing the results of economic analyses of the two agents suggests palivizumab may be the more cost-effective option in the population for which RSV prophylaxis is recommended. Over time, the acquisition cost of RSV prophylaxis agents, a major cost driver, may decrease, and more acceptable outcomes of economic analyses may result. Albeit important, the results of economic analyses are not the only tool that decision makers rely on, as population-specific risk factors, and efficacy and safety data must be considered when developing treatment guidelines and making clinical decisions.

AAP Publications Retired or Reaffirmed, October 2006

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WITHDRAWN: Immunoglobulin for preventing respiratory syncytial virus infection.

Respiratory Syncytial virus, the most important cause of lower respiratory tract infections in infants and young children in industrialized countries, is associated with increased morbidity in premature infants with or without bronchopulmonary dysplasia as well as those with congenital heart disease. Because of observations that lower rates of disease occur immediately after birth, presumably due to vertical transmission of maternal antibody, and animal studies where protection from pneumonia was observed through administration of immune globulin, the efficacy of passive prophylaxis in premature infants has been studied. This meta-analysis was performed to assess the effects of polyclonal respiratory syncytial virus hyperimmune globulin or monoclonal antibody in preventing RSV hospitalization, receipt of intensive care, mechanical ventilation, and mortality in those with underlying prematurity, bronchopulmonary dysplasia, or congenital heart disease. We searched the Cochrane Acute Respiratory Infections trials register and MEDLINE in March, 1999. In addition, abstracts on these topics were sought from the Pediatric Academies Meetings and the Intersciences Conference on Antimicrobial Agents and Chemotherapy for the years 1994 to 1997, inclusive. Randomized, controlled trials of prevention of RSV using immune globulin, respiratory syncytial virus immune globulin, or monoclonal RSV antibody in children with prematurity, bronchopulmonary dysplasia or congenital heart disease. Two authors independently abstracted data and assessed study quality. Only incidences could be pooled because data for durations was summarized in a manner that did not allow combining results across the studies. Four studies with a total of 2598 subjects were included in the main analysis. All were randomized controlled trials. Two trials were not blinded. Three studies examined RSV hyperimmune globulin and one examined monoclonal RSV antibody. A study of a different monoclonal RSV antibody could not be included because it has not been presented or published. The pooled Peto Odds Ratios favoring prophylaxis were 0.48 (95% CI 0.37, 0.64), 0.47 (0.29, 0.77), and 0.99 (0.48, 2.07) for incidence of hospitalization, incidence of ICU admission, and incidence of mechanical ventilation, respectively. The numbers needed to prevent one hospitalization and one ICU admission are 17 and 50 respectively. RSVIG is effective in preventing RSV hospitalizations and admission to the intensive care unit, but not in preventing mechanical ventilation. There was a non-significant trend towards a higher mortality in children given RSVIG.

Respiratory Syncytial Virus Prophylaxis

After completing this article, readers should be able to: 1. Identify risk factors for severe respiratory syncytial virus (RSV) lower respiratory tract disease in children. 2. Identify strategies for prevention of severe RSV disease among high-risk infants and children. 3. Know the recommendations for prophylaxis of RSV disease with palivizumab. RSV is the leading viral pathogen responsible for bronchiolitis and pneumonia in infants and young children worldwide. Preterm infants and children who have bronchopulmonary dysplasia (BPD) (otherwise known as chronic lung disease of prematurity) or congenital heart disease are at increased risk for severe RSV disease that requires hospitalization (Table 1). | | Hospitalization | PICU Admission | Death | |:-----------:| --------------- | -------------- | ----- | | Prematurity | 8% | 3% | 1% | | BPD (CLD) | 13% | 36% | 5% | | CHD | 10% | 4% | 0.6% | * PICU=pediatric intensive care unit, BPD=bronchopulmonary dysplasia, CLD=chronic lung disease of prematurity, CHD=congenital heart disease. Table 1. Clinical Outcomes of Respiratory Syncytial Virus Infection Among Infants and Children Who Have High-risk Conditions Education of parents and other caregivers about methods to decrease the infant’s exposure to RSV and to factors that may contribute to the severity of the RSV infection must form the basis of any RSV prophylaxis program. Because RSV is transmitted by direct or close contact with contaminated secretions and the virus is known to persist for hours on environmental surfaces and for 30 minutes or longer on hands, emphasis on hand hygiene is crucial. High-risk infants and children should not be exposed to individuals who have respiratory infections, and if at all possible, they should not be in settings (eg, child care centers) where such exposures are likely. Exposure to tobacco smoke must be eliminated because it has been associated with more severe RSV disease. These measures have the added benefit of decreasing transmission of other respiratory pathogens. In addition, all high-risk children older than 6 months of age and their contacts must receive influenza vaccine. Passive immunoprophylaxis of high-risk children with RSV immune globulin intravenous (RSV-IGIV) and palivizumab has been …

Community-acquired respiratory viruses

Community-acquired respiratory viruses

Incidence of Bronchiolitis-Associated Hospitalization Among Children in Olmsted County, Minnesota

Incidence of Bronchiolitis-Associated Hospitalization Among Children in Olmsted County, Minnesota

Revised Indications for the Use of Palivizumab and Respiratory Syncytial Virus Immune Globulin Intravenous for the Prevention of Respiratory Syncytial Virus Infections

Palivizumab and Respiratory Syncytial Virus Immune Globulin Intravenous (RSV-IGIV) are licensed by the Food and Drug Administration for use in preventing severe lower respiratory tract infections caused by respiratory syncytial virus (RSV) in high-risk infants, children younger than 24 months with chronic lung disease (formerly called bronchopulmonary dysplasia), and certain preterm infants. This statement provides revised recommendations for administering RSV prophylaxis to infants and children with congenital heart disease, for identifying infants with a history of preterm birth and chronic lung disease who are most likely to benefit from immunoprophylaxis, and for reducing the risk of RSV exposure and infection in high-risk children. On the basis of results of a recently completed clinical trial, prophylaxis with palivizumab is appropriate for infants and young children with hemodynamically significant congenital heart disease. RSV-IGIV should not be used in children with hemodynamically significant heart disease. Palivizumab is preferred for most high-risk infants and children because of ease of intramuscular administration. Monthly administration of palivizumab during the RSV season results in a 45% to 55% decrease in the rate of hospitalization attributable to RSV. Because of the large number of infants born after 32 to 35 weeks' gestation and because of the high cost, immunoprophylaxis should be considered for this category of preterm infants only if 2 or more risk factors are present. High-risk infants should not attend child care during the RSV season when feasible, and exposure to tobacco smoke should be eliminated.

Impact and cost-effectiveness of respiratory syncytial virus prophylaxis for Kansas medicaid's high-risk children.

To determine the impact of prophylactic therapy for respiratory syncytial virus (RSV) infections on subsequent hospitalizations and related lengths of stay and costs and to estimate whether prophylactic treatment was cost-effective. Retrospective cohort study of the 1999-2000 RSV season. Propensity scores were used to identify an untreated comparison group to adjust for treatment selection bias. State of Kansas Medicaid program. The study population included children 10 months or younger at the start of the RSV season or born during the season who either were premature or had chronic lung disease. All children were continuously enrolled in Medicaid throughout the season. Inpatient admission for RSV infections and associated lengths of stay and costs; cost-benefit analysis of drug costs per reduction in hospitalization costs. The RSV-preventive treatments reduced the odds of hospitalizations to 0.47, lengths of stay by 74%, and hospitalization costs by $703. Given an average drug cost of $4687, the cost-benefit ratio was 6.67. Despite the demonstrated efficacy of intravenous RSV immune globulin and palivizumab in clinical trials, use of these agents in actual practice has not generated expected outcomes in the Kansas Medicaid program. Although their use generated reductions in all 3 hospital-related outcomes, their costs overwhelmed these benefits.

Parental Emotional and Time Costs Predict Compliance With Respiratory Syncytial Virus Prophylaxis

Two agents are effective in preventing respiratory syncytial virus (RSV) hospitalization in premature infants: RSV immune globulin (RSV-IG) and palivizumab. RSV-IG is associated with greater parental emotional and time costs, which may account for the more limited adherence to recommended monthly treatment with this agent. To compare the emotional distress and time costs associated with RSV-IG and palivizumab treatments and to determine the influence of these costs on treatment adherence. We surveyed parents of 82 infants who received RSV-IG (90% of eligible) and parents of 61 infants who received palivizumab (87% of eligible) at Arkansas Children's Hospital by telephone. We measured infant distress during treatment, parental distress, parental time costs, and adherence with recommended monthly prophylaxis. Half of parents of RSV-IG recipients witnessed their infant in distress during infusion, over half (61%) were upset by observing the needle stick, and 22% observed infusion in the scalp. Fewer than 5% of parents of palivizumab recipients observed their infant in distress or were themselves distressed during treatment. A quarter of parents took time off from work for RSV-IG or palivizumab treatment. RSV-IG recipients completed 62% of recommended monthly treatments compared with 86% completed by palivizumab recipients. Increased parental distress and time costs largely accounted for the reduction in adherence to monthly treatment among RSV-IG recipients. The emotional and time costs of RSV-IG treatment far exceed those of palivizumab and predict substantial differences in treatment adherence between the 2 agents. The impact of hidden costs on treatment adherence should be included in economic evaluations of medical procedures.

Respiratory outcomes in high-risk children 7 to 10 years after prophylaxis with respiratory syncytial virus immune globulin

PurposeRespiratory syncytial virus infections have been implicated in the development of asthma. We evaluated the long-term effects of respiratory syncytial virus immune globulin, an effective prophylactic agent for the prevention of these infections in children, on respiratory and allergic outcomes in children at high risk of chronic airway disease. Subjects and methodsThirteen children at high risk of respiratory disease (mean [±SD] age, 8.6 ± 1.1 years) were evaluated using pulmonary function and allergy skin testing 7 to 10 years after they had received prophylaxis with respiratory syncytial virus immune globulin. For comparison, 26 high-risk control children (mean age, 8.5 ± 0.9 years) were also evaluated. Health outcomes data were collected from all subjects. ResultsThe children were matched for age and gestational age. There were more boys, and a lesser frequency of a lower respiratory tract infection with respiratory syncytial virus (P <0.001) in the group that had been treated prophylactically than in the controls. The ratio of the forced expiratory volume in 1 second to forced vital capacity was significantly better in children who had received immune globulin (median, 0.88; interquartile range, 0.81 to 0.91) than in the controls (median, 0.76; interquartile range, 0.67 to 0.86; P = 0.02). Children were also less atopic (2 of 13) in the respiratory syncytial virus immune globulin group than in the control group (13 of 26, P <0.04) and were less likely to have missed school (P = 0.006) or have had an asthma attack (P = 0.03). ConclusionThe results suggest that prophylaxis of respiratory syncytial virus infections in infancy may have long-term effects on respiratory and immunologic parameters relevant to the development of asthma. Larger-scale studies are needed.

Respiratory syncytial virus infection: clinical features, management, and prophylaxis.

Respiratory syncytial virus (RSV) infects almost all children by two years of age, resulting in a large number of hospital admissions in infants. Reactive airway disease is more common after RSV infection, even in previously healthy children. Management of the acute infection is supportive, but preliminary evidence suggests surfactant administration to ventilated infants may be of benefit. Whether ribavirin or corticosteroids reduce respiratory morbidity after RSV infection remains controversial. Immunoprophylaxis reduces RSV admissions, Palivizumab, a humanized monoclonal antibody, is a more cost-effective prophylaxis than RSV immune globulin. Nevertheless, the cost of prophylaxis, unless only given to very high-risk infants, exceeds savings made in reducing admissions.

Respiratory syncytial virus infections in children.

Respiratory syncytial virus (RSV) is the leading cause of lower respiratory disease in young children in both developing and developed countries. By age 2, nearly all children have been infected by RSV.The clinical manifestations range from mild upper respiratory symptoms to bronchiolitis and pneumonia. First infections are nearly always symptomatic and frequently cause lower respiratory tract disease, whereas subsequent infections are generally milder. Although children with underlying conditions such as prematurity, chronic lung disease, congenital heart disease, and immuno-suppression are at high risk for severe disease, many children without underlying conditions require hospitalization. Treatment is supportive. Immunoprophylaxis with palivizumab or RSV immune globulin may benefit children born prematurely, especially those with bronchopulmonary dysplasia. To date, the development of an effective vaccine has been unsuccessful.

Respiratory syncytial virus immune globulin: decisions and costs.

A decision analysis was used to evaluate the economic effectiveness of respiratory syncytial virus immune globulin (RSVIG) prophylaxis on selected pediatric populations at risk for developing RSV bronchiolitis or all respiratory illness-related hospitalizations. We compared costs, outcomes, and cost-effectiveness of administering RSVIG to no treatment in different pediatric populations, including those at risk of developing RSV-bronchiolitis and those at risk of developing any respiratory illness-related hospitalization. We observed that if only infants at high risk of severe RSV infections received treatment with RSVIG, a calculated cost saving of about 27,000 dollars per hospitalization prevented were realized. If the Food and Drug Administration (FDA)-approved indications for RSVIG were followed, the cost to prevent one hospitalization due to RSV bronchiolitis would be over 53,000 dollars. If the aim, however, was to prevent all respiratory illness-related hospitalizations for this broader population, a much lower cost (4,000 dollars) to prevent one hospitalization would result. In this situation, cost neutrality was possible, with a therapy cost of 2,843 dollars compared to the actual average therapy cost of 4,444 dollars. Sensitivity analysis showed that the model was relatively insensitive to all variables, with the exceptions of costs related to RSVIG and intensive care unit (ICU) admissions. We conclude that RSVIG resulted in cost savings if therapy were reserved for the infants who are at highest risk for developing severe RSV infections. RSVIG is not cost-effective for preventing RSV bronchiolitis when used according to the FDA-approved indications. Education that emphasizes frequent hand-washing, avoidance of passive smoking, and lessening exposure to sick children remains the least expensive prevention tool.

Recent advances in the management and prophylaxis of respiratory syncytial virus infection.

Respiratory syncytial virus (RSV) infection is an important cause of morbidity, particularly in prematurely born infants who have had chronic lung disease. Current therapy is essentially supportive. Overall, the results of randomized trials do not support the use of bronchodilators, corticosteroids or Ribavirin. Nitric oxide and exogenous surfactant may improve the respiratory status of those infants who require ventilatory support. Nosocomial infection can be reduced by appropriate handwashing. There is no safe and effective vaccine for use in infants. Immunoprophylaxis reduces hospitalization and requirement for intensive care. Palivizumab, a humanized monoclonal antibody, is preferred to RSV immune globulin as the immunoprophylactic agent. Immunoprophylaxis should be reserved for infants at highest risk of severe respiratory syncytial virus infection, if this strategy is to be used most cost-effectively.

Hospitalisation for RSV infection in ex-preterm infants—implications for use of RSV immune globulin

BACKGROUNDRespiratory syncytial virus (RSV) specific immune globulin is now being marketed for prevention of RSV infection in ex-preterm infants. However, there are no published UK data on the morbidity or...

Respiratory syncytial virus (RSV) immune globulin and palivizumab for prevention of RSV infection.

The efficacy, safety, administration, and advantages and disadvantages of respiratory syncytial virus (RSV) immune globulin and palivizumab for preventing RSV infection are discussed. Prevention of RSV infection has attracted considerable attention because of its dinical and economic impact. Studies have shown respiratory syncytial virus immune globulin intravenous (RSV-IGIV) and palivizumab to be effective in decreasing the number of hospitalizations and hospital days attributable to RSV. The number of intensive-care-unit admissions and the severity of RSV infection in high-risk children decreased with the use of these agents. Both agents have been well tolerated, with few adverse effects; however, their high cost necessitates strict guidelines on use. The patient populations at greatest risk are those with bronchopulmonary dysplasia, those with congenital heart disease, those with a history of apnea or respiratory arrest, immunocompromised patients, those with pulmonary consolidation on chest radiography, and those born prematurely. American Academy of Pediatrics guidelines do not preferentially recommend use of either agent; each has advantages and disadvantages. Prophylactic therapy with RSV-IGIV or palivizumab may reduce the likelihood of RSV infection in high-risk patients.

Palivizumab and respiratory syncytial virus immune globulin intravenous for the prophylaxis of respiratory syncytial virus infection in high risk infants

Palivizumab and respiratory syncytial virus immune globulin intravenous for the prophylaxis of respiratory syncytial virus infection in high risk infants

Cost-effectiveness of respiratory syncytial virus prophylaxis among preterm infants.

To evaluate the costs and benefits of two new agents, respiratory syncytial virus immune globulin (RSVIG) and palivizumab, to prevent respiratory syncytial virus (RSV) infection among premature infants discharged from the neonatal intensive care unit (NICU) before the start of the RSV season. Method. Decision analysis was used to compare the projected societal cost-effectiveness of three strategies-RSVIG, palivizumab, and no prophylaxis-among a hypothetical cohort of premature infants. Probabilities and costs of hospitalization were derived from a cohort of 1721 premature infants discharged from six Kaiser Permanente-Northern California NICUs. Efficacies of prophylaxis were based on published trials. Costs of prophylaxis were derived from published sources. Mortality among infants hospitalized for RSV was assumed to be 1.2%. Future benefits were discounted at 3%. Palivizumab was both more effective and less costly than RSVIG. Cost-effectiveness varied widely by subgroup. Palivizumab appeared most cost-effective for infants whose gestational age was </=32 weeks, who required >/=28 days of oxygen in the NICU, and who were discharged from the NICU from September through November. In this subgroup, palivizumab was predicted to cost $12,000 per hospitalization averted (after taking into account savings from prevention of RSV admissions) or $33,000 per life-year saved, and the number needed to treat to avoid one hospitalization was estimated at 7.4. However, for all other subgroups, ratios ranged from $39,000 to $420,000 per hospitalization averted or $110,000 to $1,200,000 per life-year saved, and the number needed to treat extended from 15 to 152. The results were sensitive to varying assumptions about the cost and efficacy of prophylaxis, as well as the probability of hospitalization, but were less sensitive to the cost of hospitalization. In our model, the cost of prophylaxis against RSV for most subgroups of preterm infants was high relative to the benefits realized. Lower costs might permit the benefits of prophylaxis to be extended to additional groups of preterm infants.

Immunoglobulin for preventing respiratory syncytial virus infection.

Respiratory Syncytial virus, the most important cause of lower respiratory tract infections in infants and young children in industrialized countries, is associated with increased morbidity in premature infants with or without bronchopulmonary dysplasia as well as those with congenital heart disease. Because of observations that lower rates of disease occur immediately after birth, presumably due to vertical transmission of maternal antibody, and animal studies where protection from pneumonia was observed through administration of immune globulin, the efficacy of passive prophylaxis in premature infants has been studied. This meta-analysis was performed to assess the effects of polyclonal respiratory syncytial virus hyperimmune globulin or monoclonal antibody in preventing RSV hospitalization, receipt of intensive care, mechanical ventilation, and mortality in those with underlying prematurity, bronchopulmonary dysplasia, or congenital heart disease. We searched the Cochrane Acute Respiratory Infections trials register and MEDLINE in March, 1999. In addition, abstracts on these topics were sought from the Pediatric Academies Meetings and the Intersciences Conference on Antimicrobial Agents and Chemotherapy for the years 1994 to 1997, inclusive. Randomized, controlled trials of prevention of RSV using immune globulin, respiratory syncytial virus immune globulin, or monoclonal RSV antibody in children with prematurity, bronchopulmonary dysplasia or congenital heart disease. Two authors independently abstracted data and assessed study quality. Only incidences could be pooled because data for durations was summarized in a manner that did not allow combining results across the studies. Four studies with a total of 2598 subjects were included in the main analysis. All were randomized controlled trials. Two trials were not blinded. Three studies examined RSV hyperimmune globulin and one examined monoclonal RSV antibody. A study of a different monoclonal RSV antibody could not be included because it has not been presented or published. The pooled Peto Odds Ratios favoring prophylaxis were 0.48 (95% CI 0.37, 0.64), 0.47 (0.29, 0. 77), and 0.99 (0.48, 2.07) for incidence of hospitalization, incidence of ICU admission, and incidence of mechanical ventilation, respectively. The numbers needed to prevent one hospitalization and one ICU admission are 17 and 50 respectively. RSVIG is effective in preventing RSV hospitalizations and admission to the intensive care unit, but not in preventing mechanical ventilation. There was a non-significant trend towards a higher mortality in children given RSVIG.

Questions About Palivizumab (Synagis)

To the Editor. A humanized monoclonal antibody designed for the prevention of serious disease attributable to respiratory syncytial virus (RSV) has recently been approved by the Food and Drug Administration (FDA). Palivizumab, manufactured by MedImmune, Inc (Gaithersburg, MD) and marketed as Synagis, is indicated for pediatric patients who are at high risk for severe infection with RSV. Because it is highly concentrated, it can be administered as a single monthly intramuscular injection, a significant advantage over RSV immune globulin, which requires intravenous access and is logistically challenging to administer. The results of the IMpact-RSV study,1 which provided the basis for FDA approval, included the finding that use of palivizumab was associated with a 55% reduction in the need for hospitalization attributable to RSV, compared with placebo, among high-risk children. The thoughtful commentary by Dr Storch2 included an analysis of costs associated with preventing infection in high-risk children using either RSV immune globulin or palivizumab. It states that 16 patients will have to be treated to prevent one RSV-related hospitalization. Reference is made to another analysis3that calculated that the number needed to treat (NNT) in the PREVENT trial of RSV immune globulin4 was 18. An important point that was not considered in either of these analyses was that there may have been a substantial placebo effect in both the Impact-RSV and PREVENT studies. The NIAID trial5 of RSV immune globulin demonstrated a 20.2% rate of hospitalization among control children who were at high risk, but these children were not given placebo or treated as such in the trial. Previous studies6,,7 have suggested even higher rates of hospitalization for high-risk children who were not involved in clinical trials. In the PREVENT study, 13.5% of placebo recipients were hospitalized because of RSV infection and …