Economic results of palivizumab prophylaxis using vial sharing on immunisation days


  • Conflict of interest: None declared.

9 October 2012

Dear Editor,

Respiratory syncytial virus (RSV) is the most important cause of lower respiratory tract infections in infants. Most infants younger than two years of age experience a RSV infection at least once. Although RSV infections are mild, complications are not rare, especially in high-risk infants such as premature infants, babies with significant congenital heart diseases or infants who have immunodeficiencies.[1] Palivizumab is used for the prophylaxis of RSV infections, resulting in a decreased rate of hospitalizations due to these infections. However, since the cost of this drug is considerably high, its cost-effectiveness has been controversial. In order to reduce the costs of palivizumab injections, we developed a cohort model, based on vial sharing. Ethical approval of the study was obtained from the local ethical committee.

In standard practice, eligible patients according to the criteria recommended by the Turkish Neonatal Society receive the drug on the day of their regular follow-up visit. During the 2010–2011 season, patients were contacted by telephone and called to the hospital on a specific day every month (i.e. the ‘immunisation day’). After their regular examination, the injections were administered by an experienced nurse under the surveillance of the attending neonatologist. The current recommended dose of palivizumab is 15 mg/kg, administered by intramuscular injection. The cost of the 50 mg vial of palivizumab that is available in our country (Synagis, Abbott Laboratories Ltd, Istanbul, Turkey) is 800.36 Turkish liras (TL) (US$444.64). It is stored in the refrigerator at 2–8°C, and once reconstituted, its shelf life is estimated to be six hours; multidose use of single-use vials has proven safe.[2] On the day of administration, all infants were weighed and examined. The required amount of drug was drawn by sterile injectors from the consecutive reconstituted vials. If every infant had received prophylaxis on different occasions, the remaining amount of drug would have been discarded (i.e. if a 5-kg baby were to receive 60 mg of palivizumab, requiring two vials of 50 mg, 40 mg of the second vial would be discarded). No adverse effects occurred during the whole season.

There were 130 babies requiring palivizumab prophylaxis over 5 months. Theoretically, these babies would need 1234 vials of the drug if they had received it on separate occasions. However, with our method, a total of 1027 vials were used. The aggregate estimated vial savings were 207 vials (16.8%). Only TL 820 800 (US$456 645) was spent instead of an estimated TL 987 200 (US$548 685), and the financial equivalent of these savings was TL 165 600 (US$92 040) (Table 1).

Table 1. Use of palivizumab and savings in the 2010–2011 season
 Theoretical single useActual use with vial sharingEstimated savings
  1. TL, Turkish lira.
No. of 50-mg vials1 2341 027207
Administered (mg)61 70051 34210 358
Cost (TL)987 200820 800165 600
Cost (US$)548 685456 64592 040

In palivizumab prophylaxis, costs cannot be overlooked, especially in low-resource settings. Although this study does not imply that palivizumab prophylaxis is cost-effective at all, by using vial sharing and cohorting infants on the same day (the so-called immunisation day), we obtained estimated cost savings of 16.8%, equivalent to US$92 040, which is financially significant. This method not only resulted in cost savings, but also increased the compliance of patients with immunization. Children received exactly the amount they needed, not more or less. There are limited studies on this subject. In a similar study in Italy, the amount of cost savings reached 25%.[3] In similar studies, there were significant cost savings, and none of the multi-use vials was found to be infected by bacteria.[3, 4] Only 50-mg vials are available in Turkey, and if 100-mg vials are used, cost savings may be greater. This study was done on 130 patients, but the number of patients receiving palivizumab prophylaxis all over Turkey is more than 3000, and if similar policies are implemented in other units, cost savings in the whole country may be much higher.