Respiratory syncytial virus-enriched globulin for the prevention of acute otitis media in high risk children

Recent progress in antiviral chemotherapy for respiratory syncytial virus infections

The recent progress in antiviral chemotherapy against respiratory syncytial virus (RSV) infections was reviewed. RSV infections among high risk individuals, such as premature babies, infants with congenital disease of cardiopulmonary system or immune system and the aged, hospitalised patients with immunosuppressed status are threatened, with high mortality rates and thus need anti-viral chemotherapy. Clinical efficacy of ribavirin and humanized monoclonal antibody (mAb) against RSV infections as well as experimental reports of novel anti-RSV compounds under investigation such as membrane fusion inhibitors were introduced.

Immunoglobulin for preventing respiratory syncytial virus infection

BACKGROUND

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.

OBJECTIVES

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.

SEARCH STRATEGY

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.

SELECTION CRITERIA

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.

DATA COLLECTION AND ANALYSIS

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.

MAIN RESULTS

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.

REVIEWER'S CONCLUSIONS

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.

Supply, use, and abuse of intravenous immunoglobulin

Intravenous immunoglobulin is used as a replacement therapy in primary immunodeficiency diseases as well as an immunomodulatory agent in a variety of autoimmune and inflammatory disorders. The mechanisms of intravenous immunoglobulin action are complex and, for some disorders, not well understood. This paper reviews the recent literature and discusses approved, new, and controversial indications for intravenous immunoglobulin therapy, with special emphasis on its mechanism of action.

Respiratory viral infection predisposing for bacterial disease: a concise review

Although bacterial superinfection in viral respiratory disease is a clinically well documented phenomenon, the pathogenic mechanisms are still poorly understood. Recent studies have revealed some of the mechanisms involved. Physical damage to respiratory cells as a result of viral infection may lead to opportunistic adherence of bacteria. Enhanced bacterial adherence by specific mechanisms has been documented for respiratory cells infected with influenza A virus, respiratory syncytial virus and adenovirus in both in vitro and in vivo models. To date, results of various experimental studies indicate that different mechanisms for increased bacterial adherence induced by viruses are operating for specific viral-bacterial combinations. In the present review, a number of key findings obtained during the past two decades is presented and discussed.

Respiratory syncytial virus infection

Respiratory syncytial virus (RSV), long recognised as the major viral pathogen of the lower respiratory tract of infants, has also been implicated in severe lung disease in adults, especially the elderly. This fact, and the demonstration that passive prophylaxis with either polyclonal or monoclonal antibody to RSV prevents severe lung disease in high-risk infants and children, has led to renewed interest in the immune mechanisms surrounding protection, and the development of vaccines

Upper respiratory tract infections

In reviewing recent advances in upper respiratory tract infections, we focus on five key topics. First, the use of ribavirin in the treatment of respiratory syncytial virus infection has been limited to the immunosuppressed. Prophylaxis in high-risk patients with specific immunoglobulin is effective and a new monoclonal antibody shows promise. Second, the efficacy of neuraminidase inhibitors in the treatment of influenza has become established. There are unresolved concerns about early implementation of therapy without a firm diagnosis; resource implications are enormous. Third, an outbreak of influenza due to avian influenza virus (H5N1) raised the possibility of a new pandemic. However, there was minimal person-to-person spread although much was learned about pathogenesis of infection. Fourth, evidence favoring the use of ciprofloxacin rather than rifampicin for meningococcal chemoprophylaxis is reviewed. Efficacy in eradicating nasopharyngeal carriage is excellent. Finally, the management of sore throat has been considered. This remains controversial but evidence supporting antibiotic therapy in adults is lacking. If treatment is indicated in childhood, shorter courses of antibiotics may be effective.

Respiratory syncytial virus immune globulin for prophylaxis against respiratory syncytial virus disease in infants and children with congenital heart disease. The Cardiac Study Group

OBJECTIVE

To examine the effectiveness of respiratory syncytial virus immune globulin administered intravenously (RSV-IGIV) in reducing hospitalization for treatment of RSV in children with congenital heart disease (CHD).

METHODS

Children younger than 4 years of age were randomly assigned to a treatment group receiving RSV-IGIV, 750 mg/kg, monthly or to a control group not receiving infusions. Surveillance for respiratory tract infections was carried out and management decisions were made by physicians blinded to treatment group.

RESULTS

Hospitalization for treatment of an RSV infection occurred in 32 of 214 (15%) of control children and 21 of 202 (10%) of the children receiving RSV-IGIV, a 31% reduction (P = .16). However, in infants younger than 6 months of age at study entry, 20 of 82 (24%) in the control group and 10 of 96 (10%) in the RSV-IGIV group had RSV hospitalizations (58% reduction, P = .01). The incidence of hospitalization for any respiratory tract symptomatology was lower in the RSV-IGIV group (34 of 202, 17%) than in the control group (57 of 214, 27%; P = .02). There was a significantly higher frequency of unanticipated cyanotic episodes and of poor outcomes after surgery among children with cyanotic CHD in the RSV-IGIV group (22 of 78, 28%) than in the control group (4 of 47, 8.5%; P = .009).

CONCLUSION

RSV-IGIV should not be used for prophylaxis of RSV disease in children with cyanotic CHD. RSV-IGIV did not reduce RSV hospitalization in all children with CHD, but it was effective in preventing RSV hospitalization in infants younger than 6 months of age. Further studies in these children are indicated.

Detection of rhinovirus, respiratory syncytial virus, and coronavirus infections in acute otitis media by reverse transcriptase polymerase chain reaction

OBJECTIVE

To determine the frequencies of human rhinovirus (HRV), respiratory syncytial virus (RSV), and coronavirus (HCV) infection in children with acute otitis media (AOM).

METHODS

Middle ear fluids (MEF) collected by tympanocentesis and nasopharyngeal aspirates (NPA) at the time of the AOM diagnosis were examined by reverse transcriptase polymerase chain reaction for HRV, RSV, and HCV RNA.

PATIENTS

Ninety-two children aged 3 months to 7 years during a 1-year period.

RESULTS

Virus RNA was detected in a total of 69 children (75%) and in 44 MEF samples (48%) and 57 NPA samples (62%) at the time of AOM diagnosis. HRV RNA was detected in both MEF and NPA in 18 (20%), in MEF alone in 4 (4%), and in NPA alone in 10 (11%). RSV was detected in both MEF and NPA in 12 (13%), in MEF alone in 5 (5%), and in NPA alone in 9 (10%). HCV RNA was detected in both MEF and NPA in 5 (5%), in MEF alone in 2 (2%), and in NPA alone in 9 (10%). Dual viral infections were detected in 5% of children. HRV and RSV were detected simultaneously in 2 MEF samples and in 2 NPA samples; RSV and HCV were detected in 1 NPA sample. Bacterial pathogens were detected in 56 (62%) MEF from 91 children. Viral RNA was detected in 20 (57%) MEF of 35 bacteria-negative and in 25 (45%) of 56 bacteria-positive MEF samples. No important differences in the risk of treatment failure, relapse, or occurrence of late secretory otitis media were noted between children with virus-positive and virus-negative MEF aspirates.

CONCLUSION

These findings highlight the importance of common respiratory viruses, particularly HRV and RSV, in predisposing to and causing AOM in young children.

Costs and benefits of respiratory syncytial virus immunoglobulin to prevent hospitalization for lower respiratory tract illness in very low birth weight infants

BACKGROUND

Respiratory syncytial virus immunoglobulin intravenous (RSV-IGIV) has been shown to reduce the risk of lower respiratory illness (LRI) hospitalization in preterm infants and infants with bronchopulmonary dysplasia (BPD). The purpose of this analysis was to estimate the economic costs and benefits of prophylaxis with RSV-IGIV in these groups.

METHODS

The analysis was performed from a payer's perspective and therefore included only costs and cost savings that would be realized by an insurer. Estimates of the direct costs of prophylaxis and the risk and cost of LRI hospitalization were based on data about preterm very low birth weight infants cared for at our medical center. Estimates of the reduction in risk of LRI hospitalization associated with RSV-IGIV were based on data from a randomized trial (the PREVENT Study).

RESULTS

The range of cost for a five-dose course of RSV-IGIV was estimated to be $3280 to $8800 for infants weighing 1.2 to 10.0 kg at the time of the initial dose. Risks of LRI hospitalization were estimated to be 12, 17 and 28%, respectively, for preterm infants without BPD, with mild BPD and with moderate to severe BPD. Estimates of duration and per diem cost of LRI hospitalizations were, respectively, 5 days and $971. The estimated net cost of prophylaxis per infant ranged between $5415 for a 6-kg infant without BPD to $1689 for an infant with BPD and age < or =3 months.

CONCLUSIONS

The cost of RSV-IGIV typically exceeds the cost of hospitalizations prevented by several thousand dollars. Cost minus benefit is lower for infants with BPD and infants 3 months of age or younger.

Current opinion in the management in acute otitis media

The management of Acute otitis media has been a subject of controversy. This paper discusses the the current opinion on the subject including a review of recent literature. The use and choice of antibiotics reflects the wide variation in opinion for both first line and second-line therapy. The role of tympanocentesis and prophylactic treatment is discussed. The introduction of vaccines holds new promise on the prevention of Acute otitis media. Factors affecting outcome influence the management plan especially in recurrent cases, high risk groups and treatment failures.

Respiratory syncytial virus immunoglobulin and monoclonal antibodies in the prevention and treatment of respiratory syncytial virus infection

Respiratory syncytial virus (RSV) infection is particularly severe in infants with bronchopulmonary dysplasia (BPD) and in premature infants without BPD. Attempts to develop a vaccine against RSV have been unsuccessful. Passive immunoprophylaxis of premature infants with or without BPD using a hyperimmune human globulin against RSV (RSVIg) decreases the severity of RSV infection such that the rate of hospitalization following infection is reduced by 40%. The severity of illness among hospitalized infants is also reduced. To avoid the difficulties associated with intravenous infusion of immunoglobulins, monoclonal IgG antibodies against the fusion protein of RSV have been developed. In one trial, the antibodies were ineffective, although subsequent trials using higher doses of the antibody show more promising results. Studies of IgA monoclonal antibodies directed against RSV, which are administered in the form of nose drops, are also in progress. None of these preparations appear to be effective in the treatment of established RSV infection. Each of the preparations appeared to be safe, with one exception. Infants with cyanotic heart disease who received RSVIg had an increased risk of surgical complications, perhaps related to increases in serum viscosity as a result of receiving the hyperimmunoglobulin monthly in doses of 750 mg/kg. While definitive cost/benefit analyses are pending, RSVIg may be useful in infants and children with BPD who have current or recent oxygen requirements, as well as in certain premature infants without BPD. Recommendations on the use of RSVIg are provided.

Reduction of respiratory syncytial virus hospitalization among premature infants and infants with bronchopulmonary dysplasia using respiratory syncytial virus immune globulin prophylaxis. The PREVENT Study Group

OBJECTIVE

To determine the safety and efficacy of monthly prophylaxis with respiratory syncytial virus immune globulin, intravenous (RSV-IGIV) for reduction of the incidence of RSV-associated hospitalization.

METHODS

A randomized, double-blind, placebo-controlled clinical trial was conducted at 54 centers in the United States during the 1994 to 1995 RSV season. A total of 510 children with bronchopulmonary dysplasia and/or a history of prematurity were randomized to receive either 750 mg/kg RSV-IGIV (n = 250) or placebo (1% albumin; n = 260) intravenously every 30 days. Randomized groups were well balanced at entry for demographics, RSV risk factors, and birth characteristics. Children were monitored for adverse events and for RSV-associated hospitalization from randomization through 30 days after the last infusion visit; serious adverse events were monitored for an additional 30 days. For children hospitalized with RSV, data were collected regarding the total days of RSV stay, total days of increased oxygen requirement, total days with a moderate or severe lower respiratory tract illness, and frequency and duration of intensive care unit stay and mechanical ventilation. Ninety-five percent of participants completed the protocol and 85% received a complete course of infusions.

RESULTS

The incidence of RSV hospitalization was reduced by 41% in children receiving RSV-IGIV prophylaxis; 35 (13.5%) of the children in the placebo group were hospitalized for RSV, compared with 20 (8.0%) RSV-IGIV recipients. RSV-IGIV recipients had a 53% reduction in the total number of RSV hospital days per 100 children, a 60% reduction in the number of RSV days with increased oxygen requirement, and a 54% reduction in the number of RSV hospital days with a moderate or severe lower respiratory tract illness. In addition, children receiving RSV-IGIV had a 38% reduction in hospitalization for respiratory illness of any cause and a 46% reduction in total hospital days for respiratory illness per 100 children. RSV-IGIV was safe and well tolerated, with a safety profile similar to other IGIV preparations. Between 1% to 3% of children had medically significant adverse events related to RSV-IGIV administration.

CONCLUSIONS

Monthly administration of 750 mg/kg of RSV-IGIV was safe and well tolerated and was effective in reducing the incidence and total days of both RSV hospitalization and overall respiratory hospitalization in infants with a history of prematurity or bronchopulmonary dysplasia or both.