The German startup TimeTeller has developed an at-home saliva testing kit that helps individuals understand their internal daily rhythm, in a step aimed at giving timing a more prominent role in personalized medicine, particularly cancer treatment. The company says its long-term goal is to identify the times when treatments are most effective and best tolerated for each patient.
TimeTeller was founded on research led by Angela Relógio, a physicist-engineer and molecular biologist who studied oncology, circadian biology and systems medicine in Germany before leaving academia. Her observation that cancer patients stopped or changed treatment because of side effects prompted her to investigate whether the timing of treatment might be part of the problem, alongside the type of treatment itself.
What does the test measure?
The test focuses on a person’s circadian rhythm data, rather than simply classifying them as a morning or evening person. Clinics focused on longevity use this data to provide personalized guidance related to sleep, nutrition, light exposure and physical activity.
Relógio explains that the direct-to-consumer test cannot on its own determine the optimal time to administer a specific cancer treatment. Such conclusions must be calculated separately for each drug and in the context of clinical studies, a point that limits interpreting the product as an independent treatment tool or as a substitute for a physician’s decision.
From the laboratory to clinical use
Relógio personally financed the company’s first patent, and TimeTeller then spun out of Charité – Universitätsmedizin Berlin. The company later moved to the Hamburg Medical School, which provided it with access to patients and funding, as well as a safety net for its 10-person team if the company was unable to pay salaries.
Biochemist and market-access specialist Benjamin Dose also helped found the company. TimeTeller entered into a partnership with the German health insurance company Techniker Krankenkasse, which began reimbursing the cost of the test for a group of cancer patients. According to Relógio, the two parties are preparing to expand access to include a larger number of the insurer’s 12 million members.
Why does this development matter?
The project offers a practical application of the idea that biological processes do not occur independently of time, but it also highlights the difference between measuring the circadian rhythm and proving that the timing of a specific drug will improve clinical outcomes. While the test can currently be used for personalized lifestyle guidance, its direct therapeutic impact in oncology remains linked to the results of clinical studies specific to each treatment.
TimeTeller is exploring other possibilities in metabolic diseases such as diabetes, neurodegenerative diseases such as Alzheimer’s, as well as performance and women’s health, although cancer remains its primary mission. Open questions include the extent to which these measurements can actually improve outcomes when integrated into treatment protocols, and how individual data can be converted into verifiable clinical decisions.