Researchers have found three to four doses of the preventative drug palivizumab protect at-risk infants from a serious respiratory virus as effectively as five doses. The Canadian Pediatric Society recently revised their national guidelines for the administration of palivizumab in response to the collaborative research conducted at CFRI and BC Children’s Hospital. 

CFRI investigator Dr. Pascal Lavoie and Medical Director of the BC RSV Immunoprophylaxis Program Dr. Alfonso Solimano are lead authors of the study published on December 28, 2015 in JAMA Pediatrics

Respiratory syncytial virus (RSV) is a common virus that infects the lungs and respiratory tract. In adults and healthy children, RSV causes mild symptoms similar to those caused by the common cold. However, in vulnerable infants, including those born prematurely and those with health conditions affecting their lungs or heart, RSV can lead to bronchiolitis, a life-threatening inflammation of the lungs and respiratory tract that often requires hospitalization.  

Infants at high risk for complications from RSV receive injections of a drug called palivizumab, an engineered antibody that blocks the RSV virus from causing infection. Since palivizumab was introduced in the 1990s, most high-risk babies in Canada have received five injections of the drug over the course of the winter when RSV infections usually occur. 

The five injection schedule costs about $10,000 per child per year, which limits the drug’s broader use. In 2010, in response to changing practice guidelines in the United States and other countries, British Columbia introduced a pioneering reduced dosing schedule. Lower risk infants began receiving three injections of the drug and higher risk infants received four injections.  

Researchers collected data on the health outcomes from 1,180 babies receiving palivizumab at clinics across BC from 2010 to 2014. They also tested the levels of RSV-antibodies in blood from a sample group of the babies.

“We found that the reduced schedule is safe and effective and babies who receive three or four doses are just as well protected as babies who receive five doses of palivizumab,” Dr. Alfonso Solimano says. Babies on the reduced schedule were no more likely to be hospitalized with RSV than babies who received five doses. Researchers also found babies receiving three or four doses had adequate levels of RSV antibodies in their blood samples. When babies receive five doses, they’re likely getting more antibodies than they need to prevent infection. 

“We’ve reduced costs and reduced the imposition on families without losing any protection for babies,” says Dr. Lavoie.

In response to the success of BC’s program, the Canadian Pediatric Society (CPS) changed their national guidelines in June 2015. CPS now recommends that vulnerable infants receive three to five doses of palivizumab depending on their individual risk factors. 

“This is a wonderful example of how scientists and physicians can work together to improve clinical practice,” says Dr. Lavoie. “Doctors at BC Children’s Hospital implemented this program and CFRI researchers showed it was safe and effective. By working together, we were able to change care practices in a relatively short period of time.” 

Dr. Pascal Lavoie is an investigator at CFRI, a Neonatologist at BC Children’s Hospital and BC Women’s Hospital and Health Centre, and an Associate Professor in the UBC Department of Pediatrics. Dr. Alfonso Solimano is a BC Children’s Hospital and BC Women’s Hospital and Health Centre, and a Clinical Professor in the UBC Department of Pediatrics. Dr. Stuart Turvey, CFRI investigator and Director, Clinical Research, Jennifer Claydon, Research Coordinator in the Division of Neonatology, and Dr. Nico Marr, a postdoctoral fellow in the UBC Department of pediatrics at the time of the research, were also authors of the study. 

This research was made possible by support from BC Children’s Hospital Foundation, the BC RSV Immunoprophylaxis Program, the Canadian Institutes of Health Research and the Michael Smith Foundation for Health Research. 

Read more:

Pascal M. Lavoie, Alfonso Solimano, Richard Taylor, Eddie Kwan, Jennifer Claydon; Stuart E. Turvey, Nico Marr. Outcomes of Respiratory Syncytial Virus Immunoprophylaxis in Infants Using an Abbreviated Dosing Regimen of Palivizumab in JAMA Pediatrics, December 28, 2015. doi:10.1001/jamapediatrics.2015.3235