Cost-effectiveness Analysis of Nirmatrelvir/Ritonavir Compared with Molnupiravir in Patients at High Risk for Progression to Severe COVID-19 in Japan.

Background: Nirmatrelvir/ritonavir (NMV/r) and molnupiravir are oral antiviral drugs approved for the treatment of early symptomatic patients with mild to moderate COVID-19 at high risk of progression to severe disease in Japan.

Objective: This study evaluated, from a Japanese payer perspective, the cost-effectiveness of NMV/r compared with molnupiravir among patients with COVID-19.

Methods: This cost-effectiveness model describes the COVID-19 disease history and the impact of antiviral treatment on short-term and long-term outcomes. Nirmatrelvir/ritonavir was compared with molnupiravir, and in the scenario analysis NMV/r was compared with standard of care over a lifetime horizon.

Results: When compared with molnupiravir, NMV/r showed higher quality-adjusted life years (QALYs) (15.752 vs 15.739) and higher total cost (¥6 248 014 vs ¥6 245 829 [US