Palivizumab Prophylaxis among Infants at Increased Risk of Hospitalization due to Respiratory Syncytial Virus Infection in UAE: A Hospital-Based Study

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..

Impact of immunoprophylaxis with palivizumab on respiratory syncytial virus infection in preterm infants less than 35 weeks in Colombian hospitals

OBJECTIVE

To evaluate the impact of immunoprophylaxis with palivizumab in preterm infants less than 35 weeks in terms of hospitalization rate, intensive care unit requirement, and mortality.

METHODS

A prospective cohort study was conducted at six Colombian hospitals. Preterm infants less than 35 weeks who received at least one dose of palivizumab during the first 6 months of life were included. The primary outcome was the hospitalization rate related to respiratory syncytial virus (RSV) infection.

RESULTS

A total of 222 newborns participated in the study; 204 (91.8%) completed the 6-month follow-up, and three died during the study. 88.7% received a second dose of palivizumab, 79.7% a third, 34.7% a fourth, and 25.2% a fifth. The nonadjusted incidence rate of RSV infection was 2.4%, and the overall RSV-positive hospitalization rate was 1.9%. The proportion of patients that required Neonatal Intensive Care Unit (NICU) and mechanical ventilation in relation to RSV infection was 1.4%. Discharge with home oxygen, pulmonary dysplasia, and being younger than 6 months were significantly associated with respiratory infection. Furthermore, exposition to cigarette smoke was the only factor associated with increased risk of hospitalization. The group that required hospitalization received fewer doses of palivizumab (p = 0.049). No discontinuation of treatment due to adverse events were reported. No death was judged to be related to palivizumab.

CONCLUSION

The hospitalization rate and the need for NICU admission were lower than those reported in the literature. In this real-life setting, palivizumab appears to be effective in preventing serious cases of RSV infection.

Immunoinformatics-Aided Analysis of RSV Fusion and Attachment Glycoproteins to Design a Potent Multi-Epitope Vaccine

Respiratory syncytial virus (RSV) usually causes respiratory tract infections of upper airways in infants and young children. Despite recent medical advances, no approved vaccine is available to control RSV infections. Therefore, we conducted an immunoinformatics study to design and evaluate a potential multi-epitope vaccine against RSV. Sequence-based analyses of the glycoproteins F and G revealed a total of eight CD8 T-cell and three CD4 T-cell epitopes after considering antigenicity, binding affinity and other parameters. Molecular docking analysis confirmed that these T-cell epitopes developed strong structural associations with HLA allele(s). By integrating these prioritized epitopes with linkers and a cholera toxin-derived adjuvant, a multi-epitope vaccine was designed. The developed vaccine was found to be stable, non-allergenic, flexible and antigenic. Molecular docking analysis revealed a striking mean HADDOCK score (−143.3) of top-ranked vaccine-TLR cluster and a Gibbs free energy change (ΔG) value of −11.3 kcal mol−1. As per computational immune simulation results, the vaccine generated a high titer of antibodies (especially IgM) and effector T-cells. Also, codon optimization and in silico cloning ensured the increased expression of vaccine in Escherichia coli. Altogether, we anticipate that the multi-epitope vaccine reported in this study will stimulate humoral and cellular responses against RSV infection, subject to follow-up experimental validation.

Effectiveness of Palivizumab Against Respiratory Syncytial Virus Hospitalization Among Preterm Infants in a Setting With Year-Round Circulation

BACKGROUND

The year-round respiratory syncytial virus (RSV) circulation in tropical regions leads to different transmission patterns and burden of disease among infants born very preterm.

METHODS

We conducted a retrospective cohort study to estimate the effectiveness of palivizumab in preventing RSV hospitalization at 6 and 12 months after discharge, among infants born at <32 weeks' gestation in our tropical setting.

RESULTS

A total of 109 infants (26.3%) received palivizumab at discharge, of 415 who were eligible. All patients received ≥4 doses, with 105 infants (96.3%) completing 5 doses. Within 1 year after discharge, there were 35 RSV-associated admissions (3 [2.8%] in the palivizumab vs 32 [10.5%] in the nonpalivizumab group; P = .02). After adjustment for confounders, the effectiveness of palivizumab against RSV hospitalization was estimated to be 90% (95% confidence interval, 10%-99%) up to 6 months after discharge. The median time to RSV hospitalization was shorter in the nonpalivizumab than in the palivizumab group (median [range], 155 [15-358] vs 287 [145-359] days, respectively; P = .11). Five infants (14.3%), all from the nonpalivizumab group, required admission to the intensive care unit.

CONCLUSIONS

In our setting with year-round RSV circulation, palivizumab prophylaxis was effective in reducing RSV hospitalization among high-risk preterm infants of <32 weeks' gestation within the initial 6 months after discharge.