Impact of oral early antiviral therapies for mild-moderate COVID-19 in the outpatient’s setting during Omicron era: a pharmacoeconomic analysis

Background: Molnupiravir (MOL) and nirmatrelvir/ritonavir (NIR) have been shown to reduce mortality and hospital admissions in high-risk patients with mild to moderate COVID-19. However, there is limited data on the pharmacoeconomic impact of these antivirals in the Omicron era. This study aimed to assess the medical costs associated with the use of MOL and NIR, comparing them to those incurred by individuals who opted not to receive treatment.
Methods: The study included the first 50 vaccinated patients per month who developed mild to moderate COVID-19 and were treated with oral antivirals at Padua University Hospital between February 1, 2022, and June 30, 2022. A control group was comprised of consecutive patients who met the criteria for antiviral therapy but chose not to receive treatment during the same period. The two groups were compared in terms of costs related to emergency department visits and hospitalizations, which were the primary outcomes.
Results: A total of 961 patients were included, with a mean age of 67.72 ± 15.19 years and 49% male. The most common comorbidities were cardiovascular disease (57%), obesity (18%), and diabetes mellitus (18%). Of the patients, 251 (26%) were treated with MOL (group A), 252 (26%) with NIR (group B), and 458 (48%) refused antiviral therapy (group C). While the early treated groups (A and B) generally showed more favorable outcomes, no significant differences were observed between group A and group C, or between group B and group C, in terms of hospitalization or emergency department visits. However, total direct medical costs were significantly higher in both group A (671.42 ± 460€) and group B (1008.42 ± 1562€) compared to group C (446.58 ± 4977€). The primary cost driver was the cost of antiviral therapy. The average hospitalization costs were as follows: group C, 19,334.3 ± 27,030€; group B, 8956.2 ± 7412€; and group A, 10,267.2 ± 7412€.
Conclusions: In the Omicron era of the COVID-19 pandemic, the use of early oral antiviral treatments in vaccinated individuals was associated with higher medical costs compared to not receiving treatment, primarily due to the cost of the antiviral drugs. To improve resource allocation efficiency, policies aimed at reducing drug costs should be pursued, and further pharmacoeconomic studies are needed.