OBJECTIVES: Not only may SARS-CoV-2 infection result in immediate respiratory symptoms, but it can also lead to a post-acute COVID-19 syndrome (PACS), lasting several months after recovering from the infection. Nirmatrelvir/ritonavir is an antiviral agent for older adults at increased risk for progression to severe COVID-19, regardless of vaccination status. Both the pivotal EPIC-HR study and real-world evidence have shown that the drug is efficacious in improving patient health outcomes. This study assessed the cost-effectiveness of nirmatrelvir/ritonavir compared to standard of care (SoC) from a societal perspective in Sweden.

METHODS: A closed-cohort, static cost-effectiveness model was developed using a decision tree for the first year, and a Markov model for the life-time horizon. The model accounted for symptom days, hospitalizations, ICU-admissions, quality of life, mortality, treatment costs, PACS and productivity losses. The cost-effectiveness was assessed for 60-year-old patients by varying the underlying absolute risk of hospitalization (1-5%). Scenarios included variation of the effectiveness, i.e. relative reduction of hospitalization and death (56.3%-89.6%), average healthcare costs of PACS (SEK 0–50,000) and exclusion of indirect costs. Quality-adjusted life years and costs were accumulated over the patients’ life expectancy and the incremental cost-effectiveness ratio (ICER) was calculated.

RESULTS: At different underlying hospitalization risks, effectiveness of 89.6% and average healthcare costs per PACS case of SEK 25,000, the ICERs ranged from SEK 30,855 to 466,968. Scenarios testing the lowest effectiveness, PACS cost set to SEK 0, and excluding productivity losses resulted in ICERs ranging from SEK 189,216 to 495,579 at hospitalization risks of 2-5%, showing that the underlying absolute risk of hospitalization was the main driver of the results.

CONCLUSIONS: This study suggests that utilization of nirmatrelvir/ritonavir is cost-effective compared to SoC in all scenarios tested, given the prevailing willingness-to-pay thresholds in Sweden, except when the underlying risk of hospitalization is below 2%.