A survey of palivizumab for infants with cystic fibrosis in the UK

Palivizumab is a humanised monoclonal antibody to respiratory synctial virus (RSV) that has been advocated as a potential prophylactic treatment in at‐risk infants (ex‐preterm).¹ Infection with RSV in cystic fibrosis may be a factor in the development of early lung disease and acquisition of bacterial pathogens. We aimed to determine the number of infants with cystic fibrosis in the UK who would be potential candidates for palivizumab prophylaxis and to quantify hospitalisation rates and mortality from RSV in this cohort. We conducted a national questionnaire study of 42 cystic fibrosis centres over the winter RSV season of 2005–6. Data were sought on patient population (number of infants born after October 2004), admissions with RSV infection and palivizumab use. Testing for RSV infection occurred where clinically indicated. Questions were asked on the likelihood of prescribing palivizumab, if funding were not an issue, and on the significance of RSV infection in the pathogenesis of early cystic fibrosis lung disease (scale: 1, not likely to 10, very likely).

In all, 34 centres responded (81%). A total of 143 infants with cystic fibrosis aged <1 year (mean 4.2 infants/centre) were identified. Of these, 70 infants were diagnosed by newborn screening (48.6%); 16 (11.2%) of the 143 infants were hospitalised owing to RSV infection; none required paediatric intensive care unit admission and none died; 14 (9.8%) infants received palivizumab between three cystic fibrosis centres, and one of these infants was subsequently hospitalised with RSV infection (other risk factors for this infant were not reported). Two of the three centres that used palivizumab had a local funding agreement negotiated into annual costings and offered RSV prophylaxis to all their patients <1 year of age. The likelihood of prescribing palivizumab if funding were not an issue was rated as a median of 6.5. The significance of the role of RSV in the pathogenesis of early cystic fibrosis lung disease was rated as a median of 5.0.

This survey highlights several issues regarding treating infants with cystic fibrosis using palivizumab. Subjectively, most respondents consider RSV infection important in cystic fibrosis lung pathogenesis and, if funding were not an issue, would prescribe palivizumab. However, there are no data from randomised controlled trials to support this,² and our data suggest that designing such a trial would require an unfeasibly large number of participants to show a clinically relevant reduction in hospitalisation. Given the importance doctors place on the long‐term consequences of RSV infection in cystic fibrosis pathogenesis, reduction in hospitalisation may not be an appropriate outcome measure. Again, studies that evaluate longer‐term outcomes that correlate with respiratory well‐being are impractical. We are in a difficult situation; there is no national guidance on the use of palivizumab for infants with cystic fibrosis, and it is unlikely that evidence of efficacy from well‐conducted randomised controlled trials will become available to support its use, yet cystic fibrosis teams believe that prevention of RSV infection is intuitively a good policy, and a few have already organised local funding support under the umbrella of a “chronic paediatric respiratory illness”. Engaging in RSV prophylaxis is a major undertaking for families of infants with cystic fibrosis, and our survey suggests that, given the current lack of an evidence base, only a minority of cystic fibrosis centres in the UK are advocating such a policy.