Jan. 18, 2022 -- Commercial and Medicare Advantage insurers are spending an estimated $129.7 million annually on ivermectin prescriptions for COVID-19, even though the antiparasitic drug has not been shown to work against the virus, according to a new JAMA study.

The researchers analyzed a sample of a prescription drug database covering the period from Dec. 1, 2020, through March 31, 2021. Ivermectin prescriptions for COVID-19 surged in the United States at the end of 2020, according to the paper.

The investigators identified oral ivermectin prescriptions dispensed during the study period, excluding those for patients who lacked continuous enrollment or who had a diagnosis code for a parasitic infection during the week before the prescription. The researchers assumed the remaining prescriptions were for COVID-19.

Of the 5,939 ivermectin prescriptions written in this sample, 348 (5.9%) were excluded. Of the remaining 5,591 prescriptions, 4,700 (84.1%) were for privately insured patients. The average age of those patients was 51.8 years.

Average out-of-pocket spending on the ivermectin prescriptions was $22.48 for privately insured patients and $13.78 for Medicare Advantage patients. Average insurer reimbursement was $35.75 and $39.13, respectively. Aggregate total spending was $273,681 for privately insured patients and $47,143 for Medicare Advantage patients, of which insurer reimbursement represented 61.4% and 74%, respectively.

To estimate the U.S. insurer spending on ivermectin prescriptions for COVID-19, the authors measured private and Medicare plan spending on these prescriptions during the week of Aug. 13, 2021, the most recent week for which dispensing data was available. They used their analysis of the earlier sample to come up with those estimates.

The researchers assumed that all 88,000 ivermectin prescriptions dispensed in that week were for COVID-19, except for 3,600, the average weekly dispensing total in the 12 months before the pandemic.

They also assumed that 52% (43,888) and 28% (23,632) of the remaining 84,400 prescriptions were paid by private and Medicare plans, reflecting the overall distribution of payer type for U.S. prescriptions.

In the week of Aug. 13, 2021, private and Medicare plans paid an estimated $1,568,996 and $924,720, respectively, for ivermectin prescriptions for COVID-19, the study shows. Multiplying those amounts by 52 weeks yielded an estimated total annual payment of $129,673,240.

Restrict Coverage?

The authors noted that this wasteful spending exceeds the estimated annual Medicare spending on unnecessary imaging for low back pain. The amount of waste is even higher because their estimates don't include Medicaid spending, they said.

What’s more, by encouraging some people not to get vaccinated, the unwarranted ivermectin prescriptions probably led to more COVID-19 cases that would have increased insurance costs, they said.

The researchers suggest that insurance companies restrict ivermectin coverage by requiring prior authorization of the drug. These restrictions could reduce wasteful spending, they noted, while impacting only a small number of patients who had conditions for which the drug is needed.