CARESS: The Canadian Registry of Palivizumab

Abstract

The overall RSV-hospitalization rate in our study was within the range found in previous reports (1.3%-5.3%), although it did not mimic the declining rates of the US Palivizumab Outcomes Registry. This could be due to increased testing for RSV when hospitalized and increasing rates of prophylaxis of infants with underlying medical disorders.

Respiratory Syncytial Virus Infection Rates with Limited Use of Palivizumab for Infants Born at 29 to 31+6/7 Weeks Gestational Age

“…During the RSV season, the limited use of palivizumab in this study population resulted in an overall frequency of 4.5% for RSV-positive hospital visits, consistent with other studies, which have reported rates of 1.1% to 8.8% among premature infants who received palivizumab. 1,8,10,11 When RSV-positive infants in the NICU were excluded, only 2.8% of the infants in this study had RSV-positive hospital visits. Therefore, a risk factor-based approach for RSV prophylaxis, limiting the use of palivizumab in infants born at 29 to 31+6/7 weeks, led to reasonable rates for RSV-positive hospital visits in this population.…”

“…1 Among infants of Englishor French-speaking parents or legal guardians with a gestational age of 29 to 32 weeks in the Canadian Registry of Palivizumab (CARESS), only 1.25% were hospitalized with RSV. 8 Because Fraser Health cares for an ethnically diverse population, a significant proportion of families would have been excluded from the CARESS registry. 8 There has been wide variation in the frequency of RSVpositive hospitalizations reported in the literature.…”

“…8 Because Fraser Health cares for an ethnically diverse population, a significant proportion of families would have been excluded from the CARESS registry. 8 There has been wide variation in the frequency of RSVpositive hospitalizations reported in the literature. In the general population, the risk appears to be approximately 1% to 3%, 9,10 whereas the risk among premature infants is approximately 10% to 25%.…”

“…1,9,10 Use of palivizumab in premature infants has reduced the RSV-positive hospitalization rate to approximately 1.1% to 8.8%. 1,8,10,11 The variation in hospitalization rates is likely due to the heterogeneity of the studies, including differences among patient populations, differing criteria for hospitalization, different definitions of RSV-positive hospitalization, and fluctuations in viral virulence. It is also possible that education about prevention of infection may influence the RSV-positive hospitalization rate.…”

Reducing the burden of lower respiratory tract infections in infants in the Canadian Arctic

“…5 Some evidence of palivizumab's benefit has been reported in groups of infants in Cana da, but it was not from a randomized placebo-controlled trial. 6 Challenges in administering the drug relate to the strict four-week injection intervals and the need to recalculate the dose at each visit, which are magnified in northern Canada. These challenges and concerns of cost have led to palivizumab being recommended in high-risk populations only.…”