“There’s a bit of analysis that a hospital should do to decide whether they’re comfortable with a particular test. The hospital laboratory really needs to be involved in these decisions. They are the ones best positioned to evaluate the strengths and limitations of various diagnostic protocols.” — Joe Cummings, PhD, Vizient technology program director

Effective testing, treatment and vaccines represent three key components of the health care industry’s response to COVID-19. As the pandemic surges across much of the country, new rapid testing and treatment innovations could help turn the tables on the virus.

Vizient investigates these innovations in two recently published TechFlash reports. The first looks at new rapid antigen tests for diagnosis of COVID-19 and the second report provides an overview of extracorporeal blood filtration devices for critically ill COVID-19 patients.

“Armed with the information, members can apply their organization’s unique needs and situation to make a decision about a particular technology,” says Joe Cummings, PhD, Vizient technology program director.

Rapid antigen tests for diagnosis of COVID-19

As the number of coronavirus cases across the country soars, demand for testing is increasing. Vizient’s TechFlash: Rapid antigen tests for diagnosis of COVID-19 highlights five new tests that have received Food and Drug Administration (FDA) emergency use authorization (EUA) in recent months. Because these tests can be more readily mass produced, their availability may help alleviate nationwide testing shortages.

“These rapid antigen tests may actually push us over the edge where we finally have enough capacity to do the testing that we really need to do to be able to trace, isolate and make quarantine decisions,” says Joe Cummings, PhD, Vizient technology program director. “These tests are an important development in that regard.”

Other potential advantages of rapid antigen testing include low cost, easy sample collection, minimal infrastructure, portability and rapid results. With results available in roughly 15 minutes, providers can make more timely patient management decisions and isolation recommendations to help stop the spread of the virus.

The report notes that the primary disadvantage of the rapid antigen test is lower accuracy compared to the gold standard molecular tests that use polymerase chain reaction (PCR). “The antigen tests are just not as sensitive, especially at low viral loads,” adds Cummings. “That’s why most of them are labeled for use only in symptomatic patients, typically within the first five to seven days of symptom onset.” Because the rapid antigen tests are less sensitive, confirmatory PCR testing may be needed, leading to potential duplication of services and higher resource utilization.

Despite the lower sensitivity of rapid antigen tests, they do offer benefits where PCR tests may not be readily available, such as small or rural hospitals. They can also be used in settings where immediate results are valuable to determine clinical treatment decisions or infection control measures.

Cummings says the field of COVID-19 testing is rapidly evolving, with scores of manufacturers developing different types of tests beyond PCR, antigen and antibody testing. After reviewing the TechFlash report, he suggests that organizations examine new studies and clinical evidence before deciding about which tests to use.

Extracorporeal blood filtration devices

In some seriously ill COVID-19 patients, an excessive immune response triggers life-threatening overproduction of cytokines, which are small proteins released by immune system cells. Known as cytokine storm syndrome, this overproduction can cause an extreme and destructive inflammatory response, leading to progressive lung injury and multi-organ damage. The second recent report, TechFlash: Extracorporeal blood filtration devices for cytokine removal in COVID-19 patients, investigates four emerging blood purification technologies used for cytokine removal.

The FDA recently granted EUA to these medical devices. The technology holds great promise, as the treatment for seriously ill COVID-19 patients has been primarily supportive until now. “These devices are targeting a condition where there aren’t a lot of treatment options. In my mind, that’s really what defines innovation,” says Cummings.

These blood filters all serve a similar purpose in removing cytokines from the blood, but have slight differences in proprietary materials, filtration methods and adsorption properties. The filters can be integrated into the circuit of most systems used for continuous renal replacement therapy (CRRT) or extracorporeal membrane oxygenation (ECMO). “At some point in the future, I expect we would find that there are differences in which device is more effective based on their design differences, but it’s just not proven yet,” notes Cummings.

While the extracorporeal blood filtration devices hold potential as a treatment strategy to improve multi-organ outcomes and mortality in COVID-19 patients, many unknowns related to clinical safety and effectiveness exist. “What the evidence shows right now is a pretty consistent ability to affect intermediate outcomes, such as a decrease in interleukin-6 levels and other inflammatory biomarkers,” says Cummings. “Does it improve the organ function, survival and ICU lengths of stay? We don’t have that data yet.”

In addition, little is known about optimal timing for initiating and discontinuing cytokine removal therapy. Given the lack of treatment alternatives for very severe COVID-19 patients, deciding whether to use a blood filtration device requires a clinician’s expertise combined with risk/benefit calculations. Cummings suggests that hospitals use these devices in the context of a research study to help inform future clinical usage decisions.

Beyond COVID-19, the blood filtration technology may have a high impact on the treatment of sepsis and septic shock in the future. He notes that some pre-pandemic clinical trials were already underway for this indication and results may be available in the near future. “I think if we can prove that the filters helped treat seriously ill COVID-19 patients, it could be a silver lining in the COVID cloud,” says Cummings.

Vizient’s TechFlash reports are tools to help members evaluate innovative new technologies. Each report provides an overview of a technology and its significance, current practice and alternatives, clinical evidence, financial considerations, patient selection criteria, future developments and conclusions/recommendations.

Published: December 10, 2020