OP5 COST-UTILITY ANALYSIS OF PALIVIZUMAB FOR THE PREVENTION OF RESPIRATORY SYNCYTIAL VIRUS (RSV) INFECTION IN OTHERWISE HEALTHY MALAYSIAN INFANTS BORN AT 29-31 WEEKS’ GESTATIONAL AGE (WGA)

Asiah Kassim1, Barry Rodgers-Gray2, Bosco Paes3, John Fullarton2, Sze Chiang Lui1, Jean-Eric Tarride3,4, Xavier Carbonell-Estrany5, Ian Keary2
1Hospital Tunku Azizah, Kuala Lumpur, Malaysia;
2Violicom Medical Limited, Aldermaston, United Kingdom;
3McMaster University, Hamilton, Ontario, Canada;
4St Joseph’s Healthcare, Hamilton, Ontario, Canada;
5Hospital Clinic, Barcelona, Spain

Introduction:

Respiratory Syncytial Virus (RSV) infection is common in young children and causes significant morbidity, especially in high-risk groups like premature infants. 

Objective: 

To adapt an up-to-date cost-utility model to provide the first formal assessment of the cost-effectiveness of palivizumab versus no prophylaxis in Malaysian infants born at 29-31 weeks’ gestational age (wGA). 

Methodology:

All 29-31wGA infants were considered in a decision tree in which they received palivizumab or no prophylaxis. Subsequently, infants experienced either a respiratory syncytial virus (RSV)-associated hospitalisation (RSVH), medically-attended, non-hospitalised RSV-infection (MARI), or were uninfected/non-medically attended. Palivizumab reduced the RSVH rate by 63.3% (baseline rate: 11.6%). Mortality (0.43%) was applied only to infants admitted to the intensive care unit. All survivors could experience respiratory morbidity for ≤18 years. Vial sharing (5% wastage) was permitted (note: palivizumab vials are single use only), with outcomes modelled over a lifetime time horizon with 3.0% discounting. Commensurate with local RSV epidemiology and clinical practice, infants were assumed to receive an average of 4 doses of palivizumab (MYR3551.02/100mg vial). 

Results:

Palivizumab generated a cost/quality-adjusted life year (QALY) of MYR40,255 versus no prophylaxis. For direct costs only and direct and indirect costs combined, the cost/QALY was MYR 40,255 and 39,729, respectively. The model was most sensitive to palivizumab cost, long-term morbidity rates, non-prophylaxed hospitalisation rate and palivizumab efficacy in deterministic sensitivity analyses (±20% on main variables). Probabilistic analyses (10,000 iterations) resulted in incremental costs of MYR43,523/QALY, with a 50.4% probability of cost-effectiveness at a MYR44,143 willingness-to-pay threshold. 

Conclusions: 

This new analysis, the first cost-utility analysis of palivizumab in Malaysia, found palivizumab to be cost-effective in 29-31wGA infants (versus no prophylaxis). The model could be further improved by increased availability of local RSV epidemiological data.