17 - Cost-Effectiveness of Respiratory Syncytial Virus Prophylaxis in Preterm Infants 29-35 Weeks’ Gestation

Poster Number: 17
Publication Number: 17.338

Tianzhou Yu, University of Southern California, Los Angeles, CA, United States; Leah Yieh, Children's Hospital Los Angeles, Los Angeles, CA, United States; Cynthia Gong, Children's Hospital Los Angeles, Los Angeles, CA, United States

Background: Respiratory syncytial virus (RSV) hospitalization rates have increased since the American Academy of Pediatrics updated guidelines in 2014 to recommend against the use of palivizumab for preterm infants 29 – 35 weeks’ gestational age without additional risk factors. A new treatment candidate, nirsevimab, is being developed to target this population but has not been economically evaluated.

Objective: To compare the cost-effectiveness of palivizumab with standard care (no prophylaxis) in preterm infants 29-35 weeks’ gestation and estimate the cost-effective price for nirsevimab.

Design/Methods: Using a theoretical cohort of preterm infants, a hybrid decision tree and Markov model was constructed to predict the RSV clinical course in the first year of life and sequelae in the subsequent four years from the healthcare and societal perspectives. Costs, utilities, and probabilities for the model were derived from a comprehensive literature review. The model calculated costs and quality adjusted life-years (QALYs) to produce an incremental net monetary benefit (iNMB) evaluated at a willingness-to-pay (WTP) threshold of $150,000/QALY. Deterministic and probabilistic sensitivity analyses were performed to assess the impact of assumptions. A threshold analysis was conducted to determine the cost-effective price for nirsevimab.

Results: Palivizumab cost $9,575 and $9,606 more compared to standard care from a healthcare and societal perspective, respectively, with 0.0019 QALYs gained per patient over 5 years, resulting in iNMB of -$9,291 and -$9,322 from each perspective, respectively (Table).  The result was robust to parameter uncertainties, and probabilistic sensitivity analysis revealed that palivizumab was not cost-effective compared to standard care in 100.0% of the Monte Carlo simulations using a WTP threshold of $150,000/QALY (Figure). Using a societal perspective, the threshold analysis suggested that nirsevimab would be cost-effective compared with standard care and palivizumab if priced below $1,932 and $11,254 per patient, respectively.Conclusion(s): Within our given budget constraint, palivizumab is not cost-effective compared to standard care for preterm infants 29 – 35 weeks’ gestational age that are otherwise healthy. Nirsevimab, if priced appropriately, may be a cost-effective alternative.
Table: Incremental Net Monetary Benefit (iNMB) of Palivizumab vs. Standard CareQALYs (quality adjusted life-years)
iNMB (incremental net monetary benefit)
Figure: Incremental Cost-Effectiveness, Palivizumab vs. Standard CareWTP (willingness-to-pay)
QALY (quality adjusted life-years)