OBJECTIVES: To provide an up-to-date evaluation of the cost-effectiveness of palivizumab versus no prophylaxis in 32–35 weeks' gestational age (wGA) Colombian infants identified as moderate- to high-risk of respiratory syncytial virus hospitalization (RSVH) by the International Risk Scoring Tool (IRST).

METHODS: Systematic reviews and expert clinical and pharmacoeconomic input informed the development of a decision tree model for palivizumab versus no intervention. Infants experienced either RSVH, emergency room medically attended RSV infection (MARI), or remained uninfected/non-attended. RSVH rates were predicted using a Colombian-specific adaptation of the IRST. Palivizumab efficacy (82.2% relative reduction in RSVH) was derived from 32–35wGA infants in the IMpact-RSV trial. Hospital outcomes and costs were drawn from Colombian studies. Mortality (3.6%) was applied only to infants admitted to intensive care (7.8% of RSVH infants). The cost of prophylaxis was calculated using Colombian prices, an estimate of birthweight in 32–35wGA infants based on Colombian birth statistics and a growth algorithm. The base case adopted the healthcare provider perspective and a lifetime horizon and considered prophylaxis of moderate- and high-risk infants (5.0% discounting) with the possibility of 18 years of respiratory morbidity. Vial sharing was assumed to be implemented for 70% of infants, in line with current clinical practice (Note: Synagis vials are single use only).

RESULTS: For moderate- and high-risk infants, the cost per quality-adjusted life year (QALY) was COP $33,072,034 (USD $8,335). Probabilistic sensitivity analyses (10,000 iterations) resulted in a mean of COP $35,861,093/QALY (USD $9,038), with a 84.9% probability of palivizumab being cost-effective at a COP $76,396,634 (USD $19,254, 3 times gross domestic product per capita) willingness-to-pay threshold. Cost-effectiveness improved in a scenario analysis that considered prophylaxis of only high-risk infants (COP $15,669,225, USD $3949).

CONCLUSIONS: From the Colombian healthcare provider perspective, prophylaxis of moderate- and high-risk 32-35wGA infants was cost-effective versus no intervention.