A second round of laboratory cost projections using internal UW cost accounting data for HCV antibody and traditional RNA testing, combined this time with estimated reagent and staffing costs for POC RNA testing, revealed these figures, which more fully capture laboratory expenses:
- Total laboratory cost for HCV testing in 2024: $1,103,127.
- The added costs if all screening were shifted to POC HCV RNA testing: $2,871,634; if it were only used for inpatient and ED testing: $555,123; for all ED testing: $350,397; and for the county hospital ED only: $246,143.
For POC HCV RNA testing, the cost was modeled on the Cepheid test and estimated to be $90.69 per test inclusive of reagents and staffing.
What might UW do with the insight it uncovered in its analyses? “We would probably look at bringing this test on just for the public county hospital emergency room,” Dr. Greninger says. “The positivity is high enough to warrant it, and they already have the equipment. But it’s about $250,000 a year in new laboratory costs with no clear mechanism to pay for it.”
Absorbing the higher cost isn’t the only challenge. “We would have to change the algorithm to go straight to RNA,” he says, “and we need to show that it works—that paying this extra money leads to higher cure rates of hepatitis C.”
No HCV antigen tests are FDA approved, though they are used in other countries to confirm active HCV infection. Dr. Greninger and coauthors wanted to understand what the different cost profile of antigen testing would mean for clinical laboratories. They therefore modeled the same testing scenarios using up-front combination HCV antigen/antibody testing or reflex antibody-to-antigen testing. They write, “These approaches resulted in much lower laboratory costs, and if on-site chemistry line testing is available, could potentially provide turnaround times equivalent to or better than POC HCV RNA testing.”
Their data indicate that antigen testing would miss two percent of infections based on reflexed HCV viral loads. To avoid missed infections, they modeled an algorithm by which all positive antibody but negative antigen tests are reflexed to HCV RNA testing, making it possible to identify the few missed cases but adding to the TAT.
Among the study’s limitations is its focus only on laboratory costs; it did not include clinical care costs associated with the testing.
One of the aims of the study, Dr. Greninger says, is to open the conversation. “Our overall intention is to move the policy environment—we need to get a new reimbursement to support direct one-step RNA testing.”
He says he hopes to see other laboratories’ analyses of their own testing data. “It’s helpful to have the numbers out there,” he says. Until now, “most of this has been reserved for economists, just looking at it from an overall health system standpoint.”
Dr. Greninger calls the story of HCV “one of the greatest in clinical virology.”
“We called it non-A, non-B for years,” he says. “A lot of basic science work went into figuring out how to culture it. After that, we were able to get antivirals very quickly.” The direct-acting antiviral treatment results in virologic cure for most patients who complete treatment. “You can basically cure a cancer-causing virus. That’s an incredible story.”
But once you have a curative drug, Dr. Greninger says, “it’s all about the diagnostics. You have to find the cases and get people to take the drug. You can’t cure it until you find it.”
Each health system will have to assess its own test volumes and costs to determine whether point-of-care testing is feasible. “There are tradeoffs and you have to make choices,” he says. “We want to find hepatitis C cases, and we want to cure people. We don’t want to take our eye off the prize.”
Meredith Salisbury is a writer in the New York City area.