Palivizumab Prophylaxis in Preterm Infants and Subsequent Recurrent Wheezing. Six-Year Follow-up Study.

RATIONALE: Respiratory syncytial virus (RSV) induces not only infantile recurrent wheezing but also potentially atopic asthma.

OBJECTIVES

To test the effect of RSV infection on development of subsequent atopic asthma, we evaluated whether palivizumab, an anti-RSV monoclonal antibody, by preventing severe RSV disease in the first year of life, could impact subsequent recurrent wheezing and atopic asthma at 6 years of age.

METHODS

During the 2007 to 2008 RSV season, the decision to administer palivizumab was made based on standard medical practice and an observational prospective multicenter (n = 52) case-control study in preterm infants with a gestational age between 33 and 35 weeks followed from 0 to 3 years (preceding Committee on Recurrent Wheezing study). The 52 investigators at hospitals then followed these subjects until 6 years of age, reported here (Effects of Preventive Treatment for Respiratory Syncytial [RS] Virus Infection During Infancy on Later Atopic Asthma in Preterm Infants; Scientific Committee for Elucidation of Infantile Asthma). Parents of study subjects reported the infants' physicians' assessment of recurrent wheezing, using a report card and a novel mobile phone-based reporting system using the Internet. The primary endpoint was the incidence of atopic asthma.

MEASUREMENTS AND MAIN

RESULTS

Of 444 preterm infants enrolled, 349 received palivizumab during the first year of life. At 6 years, atopic asthma was not different in the groups: 15.3 and 18.2% of infants in the treated and untreated groups, respectively (P = 0.57). On the other hand, physician-diagnosed recurrent wheezing was observed in 15.3 and 31.6% in the treated and untreated groups, respectively (P = 0.003).

CONCLUSIONS

Palivizumab prophylaxis administered to preterm infants did not suppress the onset of atopic asthma but resulted in a significantly lower incidence of recurrent wheezing during the first 6 years. Clinical trial registered with www.clinicaltrials.gov (NCT 01545245).