Long term follow-up of Palivizumab administration in children born at 29-32 weeks of gestation

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..

Lung function, allergic sensitization and asthma in school-aged children after viral-coinfection bronchiolitis

Our main objective was to compare the lung function, the rate of allergic sensitization and the prevalence of asthma at 7–9 years in children hospitalized for bronchiolitis with viral coinfection versus single viral infection. Observational study in children with previous bronchiolitis and current age 7–9 years. Clinical data were collected. Fraction of exhaled nitric oxide (FeNO) determination, spirometry and skin prick test for common aeroallergens were performed. A total of 181 children hospitalized for bronchiolitis (40 coinfections and 141 single infections), with median age of 8.3 years (IQR:7.5–9.1) were included. Single-HRV-infections showed lower basal FEV1(%) than coinfections (p = 0.04) and lower z-score FEV1 than single-RSV-infections (p = 0.04) or coinfections (p = 0.02). Also, single-HRV-infections had lower post-bronchodilator FEV1(%) and z-score FEV1 values than coinfections (p = 0.03 and p = 0.03). Single-HRV-bronchiolitis was an independent risk factor for FEV1 < 80% (p = 0.007). FeNO value > 25 ppb was detected in 21(12.5%) cases, without differences between viral groups (p = 0.768). The prevalence of allergic sensitization was similar in coinfections (31.4%) versus single infections (38.7%), (p = 0.428). The highest frequency of allergic rhinitis was observed in single-HRV patients (p = 0.004). The respiratory morbidity at 7–9 years of coinfected patients was similar to the single-HRV ones. In contrast, the likelihood of current asthma was up to 5 times higher in RSV/HRV coinfections than in the single-RSV-infections ones (p = 0.012). The respiratory morbidity at 7–9 years of age after severe bronchiolitis is significantly higher in single-HRV or viral coinfection patients that in single-RSV ones. Single-HRV-bronchiolitis is independently associated with lower lung function at school-age.

Respiratory Follow Up of the Premature Neonates-Rationale and Practical Issues

The aim of the review was to present the state of knowledge about the respiratory pathology in former premature neonates (children that were born preterm-before 37 weeks of gestation-and are examined and evaluated after 40 weeks corrected age) other than chronic lung disease, in order to provide reasons for a respiratory follow-up program for this category of patients. After a search of the current evidence, we found that premature infants are prone to long-term respiratory consequences due to several reasons: development of the lung outside of the uterus, leading to dysmaturation of the structures, pulmonary pathology due to immaturity, infectious agents or mechanical ventilation and deficient control of breathing. The medium- to long-term respiratory consequences of being born before term are represented by an increased risk of respiratory infections (especially viral) during the first years of life, a risk of recurrent wheezing and asthma and a decrease in pulmonary volumes and airway flows. Late preterm infants have risks of pulmonary long-term consequences similar to other former premature infants. Due to all the above risks, premature neonates should be followed in an organized fashion, being examined at regular time intervals from discharge from the maternity hospital until adulthood-this could lead to an early detection of the risks and preventive therapies in order to improve their prognosis and assure a normal and productive life. The difficulties related to establishing such programs are represented by the insufficient standardization of the data gathering forms, clinical examinations and lung function tests, but it is our belief that if more premature infants are followed, the experience will allow standards to be established in these fields and the methods of data gathering and evaluation to be unified.

Adherence to the 2014 American Academy of Pediatrics palivizumab prophylaxis recommendations

INTRODUCTION

This study aims to describe adherence rates to the 2014 American Academy of Pediatrics (AAP) Committee on Infectious Disease guidance document recommending which patients should receive palivizumab for prophylaxis against respiratory syncytial virus (RSV).

METHODS

A retrospective, single-center analysis of patients who received at least one dose of palivizumab between October 1, 2012, and March 1, 2017 was conducted. Data collected included demographics, medical history, palivizumab administration regimens, and incidence of RSV infection.

RESULTS

Data were collected on 457 patients who received palivizumab over five RSV seasons. Approximately half of the patients (45% and 55%, respectively) received palivizumab according to the AAP recommendations in place at the time (2012 or 2014 recommendations, respectively). One percent of patients had a breakthrough RSV infection after receiving at least one dose of palivizumab. There was no significant difference in the number of breakthrough infections before and after the 2014 recommendations were released (3 vs. 2).

CONCLUSIONS

Approximately half of the patients received prophylaxis in accordance with the 2014 AAP recommendations and infrequently suffered from a breakthrough RSV infection.

One-Week Nebulization of Mycobacterium vaccae Can Protect Against Pulmonary Respiratory Syncytial Virus Infection in Balb/c Mice

Background: Respiratory syncytial virus (RSV) infection is the most common cause of acute lower respiratory tract infection in children, leading to their death. Currently, no effective prevention and treatment methods for RSV infection are available. RSV and many other unknown viruses pose a serious threat to human health. Our previous study demonstrated that Mycobacterium vaccae nebulization can protect against allergic asthma. As RSV infection and asthma are closely related, we hypothesized that M. vaccae could protect against pulmonary RSV infection. Therefore, we evaluated the effect of M. vaccae on RSV infection in Balb/c mice. Methods: The mice were randomized into three groups: normal, RSV, and M. vaccae. One week before the RSV infection model was established, the mice in the M. vaccae group were nebulized with M. vaccae. On the fourth day after RSV infection, airway responsiveness, airway inflammation, pulmonary RSV infection, mRNA levels of pulmonary toll-like receptor (TLR) 7 and TLR8, and pulmonary NF09, acetylcholine, and epidermal growth factor regulator (EGFR) expression levels in all mice were measured. Results: The airway inflammation in the M. vaccae group was alleviated compared with that in the RSV group. In the M. vaccae group, the pulmonary mRNA level of RSV and the pulmonary expression levels of NF09, acetylcholine, and EGFR were decreased considerably, whereas the mRNA levels of TLR7 and TLR8 were increased significantly. Conclusions: One-week nebulization of M. vaccae can protect against RSV infection in Balb/c mice. The mechanism involves the regulation of neurotransmitters and expression of TLR7, TLR8, and EGFR.