Palivizumab and RSV

Palivizumab prevents respiratory syncytial virus in children

 

Why is palivizumab important? 

Respiratory syncytial virus (RSV) is the leading respiratory infection among young children. Every year there are 33.1 million RSV infections and 90.6% of these happen in low and middle-income countries. RSV can cause a cough, shortness of breath, difficulty feeding, wheezing, and running nose. In some cases, the infection can cause death, hospital admission, and long-term problems. Palivizumab (brand name Synagis) is an injection used to stop severe lower respiratory infections in children. Due to the high cost of this medication, it is important to know if it still prevents severe RSV among high-risk children.

Does palivizumab work for preventing severe RSV infection in children? 

  • Moderate to high evidence shows palivizumab is effective
  • Palivizumab lowers the chance of hospitalizations by 56 %
  • Slightly reduces chance of hospitalization for other lung infections by 22%
  • The number of days children have wheezing symptoms is down by 61%
  • Children with other illnesses such as bronchopulmonary dysplasia and congenital heart disease can benefit from these results
  • Little to no difference with changes in use of oxygen, length of stay in ICU, or number of days using mechanical ventilation

Equity: Does it work in the disadvantaged? 

90.6% of the yearly RSV infection are in low & middle-income countries. Palivizumab decreases the risk of hospitalization for respiratory illnesses in low and middle income countries. 

Intervention Delivery 

  • Included 5 RCTs with a total of 3343 participants
  • Intervention:
    • Palivizumab vs placebo
    • Palivizumab vs no intervention
    • Palivizumab vs standard care (bronchodilators, corticosteroids, oxygen supplementation, intravenous fluids, etc)
  • Palivizumab 15mg/kg was given every month (max 5 months) as an injection into the muscle
  • One study delivered palivizumab through an IV

Population and Setting 

  • Included both genders of children aged 0-24 months 
  • Children with cystic fibrosis were not included
  • Setting: outpatient settings
  • One study had included neonatal ICU infants- inpatient setting
  • 4 studies were conducted in high income countries: United States, Canada, Sweden, Germany, Poland, France, United Kingdom and Netherlands
  • 1 study was conducted in a low-middle income country: Turkey

Summary of findings table 1. Palivizumab compared to placebo, no intervention or standard care for preventing respiratory syncytial virus(RSV)infection in children

Patient or population: children (0 to 24 months) 

Setting: inpatients and outpatients
Intervention: palivizumab
Comparison: placebo, no intervention or standard care 

Outcomes

 

Anticipated absolute effects

 

Relative effect (95% CI)

 

No of participants (studies)

 

Certainty of the evidence (GRADE)

 

                                                                  Risk with placebo     Risk with            palivizumab

Hospitalisation due to RSV infection

Follow-up: 2 years

 

98 per 1000

 

55 fewer per 1000

(from 36 to 69 fewer)

 

RR 0.44

(0.30 to 0.64)

 

3343 (5 RCTs)

 

High

Mortality

Follow-up: 2 years

23 per 1000

 

fewer per 1000

(from 4 more to 13 fewer)

RR 0.69

(0.42 to 1.15)

 

3343 (5 RCTs)

 

Moderate

Adverse events

Follow-up: 150 days

84 per 1000

7 more per 1000 

(from 13 fewer to 33 more)

RR 1.09

(0.85 to 1.39)

 

2831 (3 RCTs)

 

Moderate

Hospitalisation due to respiratory-related ill- ness

Follow-up: 2 years

351 per 1000

77 fewer per 1000 

(from 11 to 133 fewer)

RR 0.78

(0.62 to 0.97)

 

3343 (5 RCTs)

 

Moderate

RSV infection

Assessed with: incidence of laboratory-con- firmed RSV-bronchiolitis

Follow-up: 2 years

195 per 1000

131 fewer per 1000 

(from 88 to 156 fewer)

RR 0.33

(0.20 to 0.55)

 

554 (3 RCTs)

 

Low

Number of wheezing days

Assessed with: rates of wheezing per day

Follow-up: 12 months

45 per 1000

27 fewer per 10000 

(from 26 to 29 fewer)

RR 0.39

(0.35 to 0.44)

 

 

429 (1 RCT)

 

High

   CI: confidence interval;   RCT: randomised controlled trial;  RR: risk ratio

 

About quality of evidence (GRADE)
High quality: Very confident that the true effect lies close to that of the estimate of the effect.
Moderate quality: Moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different.
Low quality: Confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect.
Very low quality: Very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect.

 

Relevance of the review for disadvantaged communities

Findings

Interpretation

Equity - Which of the PROGRESS groups examined

Carried out a subgroup analysis for high-income countries vs low & middle-income countries

 

Included both genders (male & female) of children aged 0-24 months with other illnesses such as bronchopulmonary dysplasia and congenital heart disease.

 

The results are applicable to most countries on a global scale except tropical regions (not studied). The results showed palivizumab decreases risk of hospitalization for respiratory related illnesses. 

 

The results of this review apply to children aged 0-24 months with certain illnesses. The results are unclear for children older than 2 years old living with diseases other than bronchopulmonary dysplasia and congenital heart disease.


 

Equity Applicability

Majority of the studies were completed in high-income countries: United States, Canada, Sweden, Germany, Poland, France, UK, and Netherlands. One study was from a low to middle- income country, Turkey.

 

The results of the review are likely transferable to other high-income countries. The results may apply for some low and middle income countries. Results may not be applicable to strictly low income countries. There may be decreased availability of hospital beds in low and middle income countries-some children with RSV are hospitalized in neonatal intensive care units. Also, the distance of nearest hospitals to receive treatment & care for RSV can vary in low and middle income countries-thus impacting access to healthcare.

Cost-equity

The cost of Palivizumab continues to remain high-$1415 USD ($1790 CDN) per 1000mg.

 

 

 Palivizumab is an expensive medication for treating RSV. People living in low and middle income countries may have limited access to this medication due to cost restraint. Studies have confirmed there is a need for significant decrease in the cost of palivizumab to increase affordability for vulnerable populations. Future research should consider the cost and potential benefits from extended use of palivizumab and its influence on equity.

 

Monitoring & Evaluation for PROGRESS groups

 

Although the goal was to study the impact of palivizumab on all children, the included studies were only conducted in high-risk populations.

 

Most studies were conducted in high-income countries with the exception of one study from a low-middle income country.

 

RSV rates fluctuate throughout yearly seasons. Understanding its seasonality has allowed clinicians to determine when to begin medication administration. There is no clear research for children living in tropical climates & regions-RSV may be present in these regions all year due to the rainy seasons.

Future studies should be conducted on healthy children who are not at risk for RSV and for children with comorbidities such as immunodeficiency disorders.

 

More studies should include children from low and middle-income countries. Research should also study children who are living in poverty & the impacts this has on RSV rates & palivizumab treatment access/efficacy/barriers. 

 

Future research should study RSV rates and the impact of palivizumab in tropical regions. This review originally intended to investigate subgroup analysis for tropical vs. non tropical regions but this was not accomplished.  

This summary is based on the following systematic review: 

Garegnani L, Styrmisdóttir L, Roson Rodriguez P, Escobar Liquitay CM, Esteban I, Franco JVA. Palivizumab for preventing severe respiratory syncytial virus (RSV) infection in children. Cochrane Database of Systematic Reviews 2021, Issue 11. Art. No.: CD013757.
DOI: 10.1002/14651858.CD013757.pub2.

Link for PDF:  Palivizumab for preventing RSV.pdf

Comments on this summary? Please contact Jennifer Petkovic.                                                                                                                                                   Summary was prepared by Jessica Tiilikainen.