With its ability to quantify past infections and potential to measure population-level immunity, serology testing adds an attractive tool to the COVID-fighting toolkit. While the initial burst of test development covered in our earlier blog entries centered on diagnostic tests, high public health demand and liberal early FDA authorization requirements resulted in a surge in antibody test providers starting in late March in the U.S. market. While thinkpieces musing on the possibility of widespread personal “immunity passports” spread through the public sphere, a mix of lax oversight and ballooning demand led to concerns about the performance and validity of the numerous serology tests entering the market. Consequently, in an effort to limit concerns such as test validation uncertainty and the risk of false positives increasing disease spread, the FDA revised its list of approved tests and its approval policy in May. With recent FDA pulls from the market, lingering scientific uncertainty about the duration and implications of antibody test results, and a cooldown in public interest, the serology testing market across the U.S. has an ever more modest outlook.Insights from the SARS-CoV-2 DxBook lend additional detail to the notion that serology testing at scale remains elusive. This database contains detailed, high-quality data on laboratory testing practices for SARS-CoV-2 diagnostics, serology, and related assays. Data is being collected on a rolling basis, with over 200 labs interviewed to date since the beginning of the crisis. This data offering is available to our clients; learn more here.

While most institutions that handle diagnostic testing do not report handling serology testing in any way, often due to low demand, a large subset of labs report some type of capacity to process these tests. The vast majority of labs involved in serology testing report that they are currently sending out such tests to major players like Quest, LabCorps, Mayo, and public laboratories. Of these, most anticipate bringing testing in-house eventually.When that in-house adoption will come, however, remains an open question. The data stretching back to mid-April shows a widening expected waiting period for bringing in-house serology testing online. Labs interviewed in late April reported that they expected to be able to bring testing in-house an average of 1.5 weeks from the date of the interview. For the first half of May, this expected waiting time had doubled to 3 weeks, and by the second half of May, labs were estimating waiting a month or more before seeing COVID-19 serology testing up and running in their institution, with this trend continuing through June. Today, pessimism about three primary barriers - serology kit approval, institutional administrative approval, and supply chain readiness - continues to mount within the laboratory community.A select sliver of interviewed labs did report serology testing up and running in their institution. Active testing relies heavily on Abbott’s kit for its Architect platform. Furthermore, recent FDA market pulls have affected some surveyed labs; one lab interviewed in April reported relying on the BioMedomics platform, since removed from the market. These institutions typically report low rates of positive results, echoing worldwide evidence showing that herd immunity remains far off.The antibody testing frenzy has slowed in recent weeks as the FDA has taken a more active approach to ensuring test quality and evidence has shown that antibodies may not persist long-term. Labs across the U.S. remain uncertain about when they will be able to bring serology testing online. Nevertheless, data shows that this outbreak will be a marathon, not a sprint; herd immunity is far from current reality, even in the hardest-hit parts of the U.S., and antibody testing will continue to play an important role in monitoring population-level changes in the pandemic. As scientists work to improve test validity and understand the link between antibodies and possible COVID-19 immunity, and as society debates notions of personal privacy, universal testing, economic recovery, and “immunoprivilege”, careful and rigorous serology testing rollout will continue to support a data-driven response to the current pandemic.

Julia daniel

Julia is a Senior Analyst at DeciBio with a focus on health technology, clinical diagnostics, and the impact of machine learning on precision medicine. Julia’s work at DeciBio includes market intelligence, voice-of-customer research, and data tools development. Connect with her on LinkedIn or reach out at daniel@decibio.com.

TRPTI SANGHVI

Trpti is a Data Analyst at DeciBio where she develops business intelligence products and services for companies in the research tools, clinical diagnostics, and health technology markets. She has experience building dynamic data visualizations, competitive intelligence tools, and market models. Connect with her on LinkedIn. Or reach out to her at sanghvi@decibio.comDisclaimer: Companies listed above may be DeciBio clients and/or customers