What is the indication for SYNAGIS (palivizumab)?

SYNAGIS (Palivizumab) Indications

SYNAGIS is indicated for the prevention of serious lower respiratory tract disease caused by RSV in high-risk pediatric patients, specifically those with premature birth (≤35 weeks gestational age) who are ≤6 months old at RSV season onset, those with bronchopulmonary dysplasia requiring treatment within 6 months who are ≤24 months old, and those with hemodynamically significant congenital heart disease who are ≤24 months old. 1

FDA-Approved Indications

The FDA label clearly defines three specific pediatric populations eligible for palivizumab prophylaxis:

Premature Infants

• History of premature birth (≤35 weeks gestational age) AND
• Age ≤6 months at the beginning of RSV season 1

Chronic Lung Disease/Bronchopulmonary Dysplasia (BPD)

• BPD that required medical treatment within the previous 6 months AND
• Age ≤24 months at the beginning of RSV season 1

Hemodynamically Significant Congenital Heart Disease (CHD)

• Hemodynamically significant CHD AND
• Age ≤24 months at the beginning of RSV season 1

AAP Refined Guidance for Specific Risk Groups

The American Academy of Pediatrics provides more granular recommendations within these FDA-approved categories:

Highest Priority: Infants Born <29 Weeks Gestation

• Infants born before 29 weeks, 0 days' gestation who are younger than 12 months at RSV season start should receive prophylaxis 2
• Maximum of 5 monthly doses throughout RSV season 2

Moderate Risk: Infants Born 29-34 Weeks Gestation

• Infants born at 29 weeks, 0 days' gestation or later may qualify based on additional conditions (CHD, CLD) rather than prematurity alone 2
• For infants 32 weeks 0 days through 34 weeks 6 days' gestation, prophylaxis requires specific risk factors 2

Chronic Lung Disease of Prematurity

• Infants <24 months with CLD requiring medical support (supplemental oxygen, chronic corticosteroids, diuretics) during the 6 months before RSV season 2, 3
• Second season prophylaxis only if continued medical support is required 2

Hemodynamically Significant CHD

• Infants ≤12 months with acyanotic heart disease receiving medication for congestive heart failure 2, 3
• Infants with moderate to severe pulmonary hypertension 2, 3
• Infants with cyanotic heart defects (consultation with pediatric cardiologist recommended) 2

Populations That Should NOT Receive Palivizumab

Hemodynamically Insignificant Heart Disease

• Secundum atrial septal defect 2, 3
• Small ventricular septal defects 3
• Mild pulmonic stenosis 3
• Uncomplicated aortic stenosis 3
• Mild coarctation 3
• Patent ductus arteriosus 3

Other Exclusions

• Down syndrome without qualifying conditions (prematurity <29 weeks, CHD, CLD, or airway clearance issues) 2
• Cystic fibrosis without clinical evidence of CLD or nutritional compromise in first year of life 2
• Adequately corrected cardiac lesions unless still requiring CHF medication 3

Special Populations for Consideration

Immunocompromised Children

• May be considered for children <24 months who are profoundly immunocompromised during RSV season 2, 3
• Children <2 years undergoing cardiac transplantation during RSV season 2

Post-Cardiopulmonary Bypass

• Additional 15 mg/kg dose should be administered after cardiac bypass or ECMO, as bypass decreases serum palivizumab by 58% 2, 3

Administration Details

• Dose: 15 mg/kg intramuscularly monthly throughout RSV season 2, 3
• Maximum doses: 5 doses for most eligible infants; 3 doses maximum for infants 32-34 weeks gestation without CHD/CLD 2
• Timing: Administered prior to RSV season commencement and monthly thereafter 1

Critical Limitation

Palivizumab is NOT indicated for treatment of established RSV disease—only for prevention. 1 The medication provides prophylaxis by passive immunization but has no therapeutic role once infection occurs.

Common Pitfalls to Avoid

• Do not discontinue prophylaxis after breakthrough RSV hospitalization; continue monthly doses as extremely low likelihood (<0.5%) of second hospitalization exists 2
• Do not use in hemodynamically insignificant heart disease, as no benefit is demonstrated 2, 3
• Do not forget post-operative dosing after cardiopulmonary bypass 2, 3
• Do not assume palivizumab prevents recurrent wheezing or reduces mortality—efficacy is limited to reducing RSV-related hospitalizations 3, 4