At-home health testing has been mired in overblown claims and outright fraud. But German startup TimeTeller, which has developed a saliva test kit to help anyone understand their circadian rhythm, is led by CEO Angela Relógio, who is the polar opposite of Theranos’ disgraced founder Elizabeth Holmes.

Relógio is a physicist-engineer and molecular biologist who spent years researching oncology, circadian biology, and systems medicine in Germany before leaving academia to build TimeTeller. She is careful about what the test can and can’t do today.

It would be easy to oversell: Relógio’s last name means “clock” in her native Portuguese, and TimeTeller has the potential to reduce side effects from cancer treatment and improve outcomes by timing treatment to each patient’s internal clock. That’s also why she’s careful to warn that TimeTeller itself operates on two timelines.

The long-term goal is to determine when cancer treatments will be better tolerated and most effective, and doing so much more granularly than just telling whether someone is a morning person or a night owl. But its direct-to-consumer kit won’t help patients figure that out on their own. “That is something that we need to calculate for every single medicine; we do that in the context of clinical studies,” Relógio cautioned.

According to Relógio, TimeTeller started accepting direct orders because of demand from longevity clinics, which focus on healthy aging and understand that individual data on a person’s circadian rhythm can be used to offer personalized advice on sleep, nutrition, light exposure, and physical activity.

TimeTeller could also apply to metabolic diseases (such as diabetes) and neurodegenerative diseases (such as Alzheimer’s), performance, and women’s health, but cancer is its core mission. It was while studying cancer that Relógio made the discovery that led her to leave academia.

She noticed that many cancer patients stopped or started their treatment because of side effects. “As a scientist, that was just impossible to watch, particularly when I was convinced that part of the problem might not only be what treatment we give, but when we give it,” Relógio said. This led her to develop the circadian rhythm test at the core of TimeTeller — which she knew had to become a company.

“I personally funded our first patent because I strongly believed that this discovery should not remain in scientific publications,” she said. The startup spun out of Berlin’s Charité university hospital but has since moved to Medical School Hamburg, which provided access to patients and funding. It also offered a fallback: backup employment for TimeTeller’s team of 10 if the company couldn’t pay them.

That’s a safety net TimeTeller may not need. Having enlisted biochemist and market access specialist Benjamin Dose as a co-founder, the startup secured a partnership with Techniker Krankenkasse, one of Germany’s largest health insurance providers. The partnership started out as a reimbursement deal in which the insurer pays back the cost of the test for a subset of cancer patients, and both sides are now ready to expand it to more of the insurer’s 12 million members, Relógio said.

Despite her caveats about the direct-to-consumer test, TimeTeller has become a solution that cancer patients can actually access. Ahead of her appearance at TechCrunch Disrupt, where Relógio appeared onstage today in San Francisco as part of our storied Startup Battlefield competition, she made clear that the company has broader ambitions: a future in which asking “when” is central to precision medicine, because “almost every process in our body is timed.”

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