At-Home Testing Beyond COVID-19

I can’t stop thinking about this graph. ↓

In the span of a few short months, at-home testing achieved ~5x the capacity of lab-based testing (thanks in part to the Biden Administration’s subsidy).

The success of at-home testing is totally unsurprising. While less sensitive than PCR, at-home tests are both more convenient and more actionable. Should I send my kid to school today? Should I walk into this conference hall? People with 15-minute antigen tests in their hands can make these decisions easily in the moment.

Also, with at-home tests, it’s practical to test daily or weekly to observe new patterns such as exposure and transmission risk, case duration, symptomatic and asymptomatic disease prevalence, and unique phenomena like the Paxlovid rebound across different demographics. This has the potential to unlock a totally new level of insight into the COVID-19 virus.

But we don’t see much at-home testing anywhere else. Outside of a few niches, like diabetic glucose monitoring and pregnancy testing, examples of at-home testing with at-home results are surprisingly sparse.

Of course, not all conditions have predictable testing needs or require immediate data. But for many, it would yield better disease tracking, rapid response, and improved patient experience (schlep avoidance, at minimum).

What would it take to extend at-home testing to other areas of health?

• Acceptance by clinical audiences — the diagnostic testing market today is largely bifurcated into clinical and consumer segments with little-to-no crossover. Clinical grade tests have unfriendly UI and reports designed for physician audiences. Consumer tests, by contrast, tend to be much easier to use, but fail to convey information in ways that are actionable for physicians. COVID tests represent one of the first crossover products that are both usable by patients and accepted by physicians (though many will still use PCR tests for accuracy). For at-home testing to scale, designing for both audiences is absolutely critical. Continuous glucose monitors (CGMs) can offer some lessons here.
• Data retention and analysis — COVID-19 antigen tests’ lack of connection to clinical or public health infrastructure is a big shortcoming, especially for disease tracking. While their simplicity is a core feature that makes them useful in any environment, the data is never stored or made available for analysis. That limits their usefulness for population-level observation and knowledge creation. Some tests offer a QR code for easy reporting which is a step in the right direction (fast and easy), but still not automatic or required.
• Reimbursement — the Biden Administration’s decision to subsidize at-home tests was a catalyst in two ways: first, it made at-home testing accessible for millions of families who couldn’t afford the $20–100+ per test cost. Next, the subsidy created a massive spike in demand that drove increased production, economies of scale, and cost reduction. Without reimbursement, at-home tests will remain a more expensive convenience play (even if cost of goods is comparable or even less than lab-based testing). Regulators, insurers, and providers need to speed up their approval of at-home testing. For well-designed products, this can actually yield cost savings and reduce the load on providers dramatically.
• Better product design for patient engagement — it goes without saying that at-home tests need to be easy to use and hard to screw up in untrained hands. When results are delivered at-home, the results, their implications, and next steps need to be clearly communicated to ensure reliable follow-up. Depending on the test, the emotional burden of the results may be heavy. Tests need to be designed to connect patients to appropriate support resources. Regulators are responsible for reviewing these criteria, and physicians should base their product recommendations on them, as well.
• Infrastructure to make sense of high-frequency data — there’s tremendous potential for new knowledge creation based on high-frequency datasets that haven’t existed in clinical care. But the infrastructure to house and make sense of hourly, daily, or weekly readings is lacking. EHRs store individual lab results but aren’t set up to identify patient or population-level trends. We need new systems for data collection and analysis to extract full value from this information without imposing onerous requirements on either data contributors (patients) or researchers.

The two billion+ COVID-19 tests that were distributed this year showed us that at-home tests with at-home results are critical to the future of diagnostics. They’re cheaper and more convenient. They have the potential to turn patients from passive participants into active managers of their health. And if we continue to embrace this future, it will lay the foundation for truly patient-centric care that delivers better quality care with less provider burden.

If you’re building or thinking about at-home testing capabilities or infrastructure, please get in touch! — sara@spero.vc.