The Cost of Antivenom: A Cost Minimization Study using the North American Snakebite Registry

Abstract

Envenomation is a global health issue, with over 9,000 encounters managed in the United States yearly. The introduction of immunoglobulin fragment antivenom has reduced the risk of hypersensitivity. This study compares treatment costs of crotaline envenomation using the Fab and F(ab')₂ antivenoms as reported to the North American Snakebite Registry (NASBR), a nationwide surveillance tool.

Methods: This was a retrospective analysis of NASBR data between 2018 and 2020. The following data points were assessed: patient demographics (age, gender, race), snake species, type of antivenom used, and treatment costs. Unit costs were estimated based on United States Centers for Medicare and Medicaid Services data. Average (mean) per patient costs from the payer perspective were calculated by multiplying resources by the unit costs. Sensitivity analyses were performed regarding cost variance and snake species. All costs reported in this study are in U.S. dollars.

Results: The average total cost of treatment was $31,343 per person, with medications contributing 72% of the total. Average total cost among patients who received Fab treatments was $33,347 per person compared to $19,747 among patients who received F(ab')₂. Antivenom costs accounted for 75% of the total cost in the Fab group and 42% in the F(ab')₂ group. F(ab')₂ required more vials than Fab (median 18 versus 10). Non-antivenom costs such as hospitalizations were higher in the F(ab')₂ group. Using average sale prices increased average total cost to $52,572; Fab remained more expensive.

Conclusion: Antivenom is the primary cost driver in snakebite treatment in North America. Treatment with F(ab')₂ resulted in lower overall costs, driven by lower cost of antivenom. F(ab')₂ did not significantly lower overall resource use except for blood product administration.

Keywords: Antivenom; Cost; Envenomation; Minimization; Pharmacoeconomics; Snakebite.