The race is on to develop a continuous glucose monitor that doesn’t require regular fingersticks, a sensor implanted under the skin or any other invasive technologies, no matter how mild.
Recent entrants in that race include Know Labs, Hagar and even Apple, which is believed to be closer than ever to achieving its goal of adding glucose monitoring capabilities to its ubiquitous smartwatch. Thanks to a nicely sized funding round that closed this week, another major contender has emerged: GraphWear, with a nanotechnology-powered sensor that it says can measure glucose with the best of them—without ever breaking the skin.
GraphWear’s $20.5 million funding round was led by Mayfield, TechCrunch reports, while MissionBio Capital, Builders VC and VSC Ventures also joined in. That’s a sizable upgrade from its previous round, which brought in a comparatively modest $4.2 million haul in 2018.
The series B financing will be used to usher the San Francisco-based startup’s wearable sensor through clinical trials, the results of which will in turn be used to support GraphWear’s eventual submission for FDA clearance or approval.
The technology is powered by graphene, a one-atom-thick sheet of carbon atoms that is extremely strong and a powerful conductor of electricity. When activated, the electrical field surrounding GraphWear’s sensor attracts molecules near the surface of the skin, which it can then analyze to measure blood sugar levels.
The readings, which the company says can come from as few as 100 to 200 molecules, are then sent via Bluetooth to a connected app, where users can track their glucose over time and receive real-time alerts if they hit specified levels.
The sensor technically measures the amount of glucose in the interstitial fluid among the wearer’s cells, rather than in the blood itself. Though not interchangeable, studies have found that the two values correlate to one another, according to the American Diabetes Association.
GraphWear’s sensor can be embedded into either a smartwatch-like wearable device strapped to the wrist or an adhesive patch attached to the torso.
Results of the first completed feasibility study of the technology have yet to be released, but Rajatesh Gudibande, co-founder of GraphWear, told TechCrunch that the study proved the sensor’s ability to generate glucose readings “comparable” to those of traditional CGMs. Once that ability has been further proven in clinical studies and, eventually, regulatory clearances, he said, the sensor could ultimately be adapted to analyze molecules for more than just glucose levels.
GraphWear’s financing arrives hot on the heels of significant updates from several of its peers in the non-invasive glucose monitor space. In August, Israel-based Hagar raked in $11.7 million to continue developing its GWave technology, which picks up on blood sugar levels by emitting radio waves, rather than requiring fingersticks or implants and is embedded into a ceramic bracelet.
Know Labs, meanwhile, unveiled a device based on similar technology late last month. The battery-powered KnowU device fits into a user’s pocket for on-demand glucose readings, powered by the company’s own radio wave-emitting sensors.