Deaths among children less than two years of age receiving palivizumab: an analysis of comorbidities

BACKGROUND: Palivizumab (Synagis) is used for prophylaxis against respiratory syncytial virus infection among children at high risk for respiratory syncytial virus disease. A number of deaths after palivizumab use among children <2 years have been reported to the Food and Drug Administration. We assessed available information, including the extent to which preexisting medical conditions may have put these children at higher than normal risk of death. METHODS: We reviewed reports of deaths to the Food and Drug Administration (June 1998 to December 2001) among children <2 years of age who received palivizumab. RESULTS: There were 133 deaths reported after palivizumab use. Median age at death was 5 months, and 54% of the children were male. At least one congenital anomaly was reported in 85 cases (64%), and 44% of cases had multiple anomalies. Of the 100 cases with reported gestational age at birth, 36% were severely premature (<28 weeks), 48% were moderately premature (28 to 36 weeks) and 16% had normal gestational age. Only 2% of all cases were full term and were born without congenital anomalies; 50% had both conditions, 34% had prematurity alone and 14% had congenital anomalies alone. A cause of death was reported for 88 (66%) cases; most (38%) died from their congenital anomalies or from respiratory infections (23%). CONCLUSIONS: Most children dying after palivizumab treatment were at increased risk of death; many had multiple congenital anomalies and/or premature birth. Patterns of outcomes and the reported medical course did not suggest that palivizumab further elevated the risk of death. Current data do not alter the safety and efficacy assessment that led to the licensure of palivizumab.