Siren’s smart socks remotely monitor foot health for diabetics

Siren, a startup developing washable smart socks designed to help remotely monitor diabetes patients, today raised $9 million. According to CEO Ran Ma, the extension to its series B funding round will be used to grow the team and meet demand for Siren’s product and services.

In response to the pandemic, companies like Current Health and Twistle have teamed up with health care providers to pilot at-home wellness-tracking platforms. Indeed, ABI Research predicts that by 2025, spending on AI in health care and pharmaceuticals will increase by $1.5 billion as a result of the novel coronavirus.

Ma, previously a biomedical engineering student at Northwestern University’s Fineberg School of Medicine, worked with Siren’s founding team to develop socks and foot monitoring systems that track issues related to inflammation, particularly in diabetics. Siren monitors foot temperature continuously at six key points, notifying wearers and their doctors via an app and text when signs of inflammation are detected.

Siren points to recommendations from the U.S. National Institutes of Health that people with neuropathy check their feet daily for signs of injury that can lead to ulcers, skin infections, and more. A 2007 study published in the American Journal of Medicine found that temperature monitoring, in contrast to visual checks alone, can improve outcomes related to ulcers by 87%.


To ensure accuracy, Siren ships replacement socks every six months. The company says its system adheres to Medicare and Medicaid Services guidance for remote patient monitoring services with support for clinical population management and decisioning tools, as well as 24-hour support for both clinicians and patients.

Ma claims that demand for Siren’s products has risen sharply during the pandemic. Monthly subscriptions in 2020 are up 19 times and the number of patients with signed contracts rose 340%, ahead of forecasted expectations for the year. Meanwhile, the number of ordering clinics more than tripled (increasing by 216%), spurring Siren to expand its workforce.

Siren secured $11.8 million earlier this year, putting its total series B funding at around $21 million. Previous investors include Khosla Ventures, Founders Fund, DCM Ventures, Gaingels, and Anathem Ventures.

Siren occupies a market overcrowded with connected and “smart” textiles that could top 10 million in sales this year, according to Tractica. In 2013, Owlet launched a sock for young children that gave information on heart rate, blood oxygen levels, sleep quality, skin temperature, sleep position, and other vitals. And Sensoria sells socks made of running-friendly fabric infused with sensors that track step count, speed, and calories burned through an app.

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