OBJECTIVES: This study evaluates the cost-effectiveness of molnupiravir against standard care for treating mild to moderate COVID-19 infection at high risk of severe disease in Singapore.

METHODS: A hybrid model comprising a decision tree followed by a life-time Markov model was constructed to assess the cost-effectiveness of COVID-19 oral antiviral therapeutics, molnupiravir, for the treatment of patients with mild-to-moderate COVID-19 at high risk of progression to severe disease from the Singapore healthcare system’s perspective. Key model inputs such as the clinical effectiveness, hospitalization and mortality rate were derived from the MOVe-OUT trial and real-world data obtained from Ministry of Health COVID-19 statistics and National Centre for Infectious Diseases (NCID) data. Health state utilities were derived from published literature and direct medical costs were obtained from local public healthcare institutions. Sensitivity and scenario analyses were performed to examine how the ICER changes when hospitalization and death probability were adjusted according to the vaccination status of base population.

RESULTS: The base case resulted in an incremental cost-effectiveness ratio (ICER) of SGD105,580 per quality-adjusted life-year (QALY) gained. One-way sensitivity analyses showed that the ICER was sensitive to the hazard ratio for hospitalization or death. Scenario analyses showed that the ICER was highly sensitive to the baseline mortality of patients with COVID-19 infection. The ICER increased substantially to SGD 211,025 per QALY gained when a lower baseline mortality rate was applied in the model to simulate a highly vaccinated population who also completed additional booster dose.

CONCLUSIONS: At its current price molnupiravir is unlikely to represent a cost-effective treatment option for people with high risk, mild to moderate COVID-19 infection in Singapore, given that most of the population had completed vaccination with an additional booster dose.