Table 3.
Most commonly observed serious AEs (reported in ≥0.5% and ≥2 participants in any treatment group during the first RSV season) in healthy term and preterm infants born ≥29 wGA, infants with CHD/CLD, preterm infants born ≤35 weeks 0 Days GA without CHD/CLD, and children with CHD/CLD entering their second RSV season.
| Healthy Term and Preterm Infants Born ≥29 wGA a | Infants Eligible for Palivizumab Entering Their First RSV Season | Children with CHD/CLD Entering Their Second RSV Season b | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Preterm Infants Born ≤35 Weeks 0 Days GA without CHD or CLD |
Infants with CHD/CLD | ||||||||
| Preferred Term, n (%) | Nirsevimab (n = 2570) |
Placebo (n = 1284) |
Nirsevimab (n = 406) |
Palivizumab (n = 206) |
Nirsevimab (n = 208) |
Palivizumab (n = 98) |
Nirsevimab/ Nirsevimab (n = 180) |
Palivizumab/ Nirsevimab (n = 40) |
Palivizumab/ Palivizumab (n = 42) |
| Bronchiolitis | 37 (1.4) | 33 (2.6) | 4 (1.0) | 0 | 7 (3.4) | 4 (4.1) | 1 (0.6) | 0 | 0 |
| Pneumonia | 21 (0.8) | 12 (0.9) | 2 (0.5) | 0 | 3 (1.4) | 1 (1.0) | 2 (1.1) | 2 (5.0) | 0 |
| Gastroenteritis | 19 (0.7) | 7 (0.5) | 0 | 1 (0.5) | 6 (2.9) | 0 | 3 (1.7) | 1 (2.5) | 1 (2.4) |
| LRTI | 16 (0.6) | 10 (0.8) | 0 | 0 | 1 (0.5) | 2 (2.0) | 2 (1.1) | 0 | 0 |
| Bronchitis | 13 (0.5) | 13 (1.0) | 3 (0.7) | 1 (0.5) | 2 (1.0) | 1 (1.0) | 0 | 0 | 0 |
| Urinary tract infection | 7 (0.3) | 8 (0.6) | 1 (0.2) | 0 | 1 (0.5) | 1 (1.0) | 0 | 0 | 0 |
| RSV bronchiolitis | 6 (0.2) | 12 (0.9) | 0 | 1 (0.5) | 4 (1.9) | 1 (1.0) | 0 | 0 | 0 |
| Upper respiratory tract infection | 6 (0.2) | 5 (0.4) | 0 | 2 (1.0) | 1 (0.5) | 1 (1.0) | 1 (0.6) | 0 | 0 |
| Viral upper respiratory tract infection | 5 (0.2) | 0 | 0 | 0 | 3 (1.4) | 1 (1.0) | 1 (0.6) | 0 | 0 |
| COVID-19 | 3 (0.1) | 2 (0.2) | 3 (0.7) | 1 (0.5) | 0 | 0 | 2 (1.1) | 0 | 0 |
| Inguinal hernia | 1 (<0.1) | 6 (0.5) | 1 (0.2) | 1 (0.5) | 0 | 0 | 0 | 0 | 0 |
| Cardiac failure | 1 (<0.1) | 0 | 0 | 0 | 1 (0.5) | 2 (2.0) | 0 | 0 | 0 |
| Failure to thrive | 1 (<0.1) | 0 | 0 | 0 | 2 (1.0) | 0 | 1 (0.6) | 0 | 0 |
| Bradycardia | 0 | 0 | 1 (0.2) | 2 (1.0) | 0 | 0 | 0 | 0 | 0 |
| Feeding intolerance | 0 | 0 | 0 | 0 | 2 (1.0) | 0 | 0 | 0 | 0 |
| Pleural effusion | 0 | 0 | 0 | 0 | 0 | 0 | 2 (1.1) | 0 | 0 |
Participants with multiple events in the same preferred term were counted once in each of those preferred terms. Participants with events in more than one preferred term were counted once in each of those preferred terms. Serious AEs were defined as death, life-threatening, requiring inpatient hospitalization, prolongation of existing hospitalization, persistent or significant disability/incapacity, important medical event, or congenital anomaly/birth defect. a Includes infants from Phase 2b weighing < 5 kg and the full MELODY enrollment cohort. b Before the second season, children with CHD/CLD randomized to nirsevimab in the first season received a single IM dose of 200 mg nirsevimab followed by 4× once-monthly IM doses of placebo (nirsevimab/nirsevimab), and those randomized to palivizumab in the first season were re-randomized 1:1 to either a single IM dose of 200 mg nirsevimab followed by 4× once-monthly IM doses of placebo (palivizumab/nirsevimab) or 5× once-monthly IM doses of palivizumab (15 mg/kg per dose) (palivizumab/palivizumab). Abbreviations: AE, adverse event; CHD, congenital heart disease; CLD, congenital lung disease; COVID-19, coronavirus disease 2019; GA, gestational age; IM, intramuscular; LRTI, lower respiratory tract infection; RSV, respiratory syncytial virus; wGA, weeks’ gestational age.