San Diego startup Glysens Inc., which is developing implantable continuous glucose monitoring (ICGM) technology, closed a $15 million incremental financing. The funds will be used to support ongoing clinical trials and development of the company’s fully implanted, long-term CGM systems, including first-in-human evaluation of the third-generation Eclipse 3 ICGM.

The round, led by previous lead investors Mcnair Interests and The Sarofim Group, brings Glysens total equity raised to more than $65 million.

“We are tremendously appreciative of this vote of confidence and continuing support from Mcnair Interests and The Sarofim Group,” said William Markle, Glysens’ president and CEO. “We have, by sheer necessity, evolved into a highly focused, biotechnology-driven company poised to deliver the first viable, long-term, fully implantable CGM solution, which eliminates any body-worn components while delivering CGM performance in line with today’s commercial standards.”

Most CGM are usually placed on the skin and require daily calibration using a fingerstick blood glucose device. Glysens’ fully implantable ICGM sensor generates real-time blood glucose readings and alerts the user when their sugar levels are too high or too low. The implant relies on two detectors – an electrochemical “main” detector that measures glucose based on a specific reaction between glucose, and oxygen and a “reference” detector that tracks background tissue oxygen levels. Glucose levels are automatically computed according to the difference between the two signals. Recalibration is required only once or twice a month.

The sensor, which is intended to last a full year, is implanted subcutaneously in the abdomen. The procedure can be performed in an outpatient setting under local anesthesia. In addition to displaying real-time readings, the device stores blood sugar values over time for trend analysis.

The company completed a FDA-approved 20-patient IDE study of the Eclipse ICGM system in early 2018. Data from that and another trial with European partners have not been publicly reported.

The next-gen Eclipse 3 system is 40% smaller than its predecessors, with no added electronics or on-body adhesive components and a targeted two-year battery life. The system communicates wirelessly via Bluetooth with an Iphone, avoiding the need for a dedicated receiver. Glysens plans to kick off the first-in-human study in the first quarter of 2021, followed by larger trials to support regulatory approval.

“We are most impressed and encouraged with the fundamental bioengineering prowess and creative problem-solving displayed by the technical team at Glysens,” said Jake Kushner, medical director at Mcnair Interests. “Fully implanted, long-term sensors have long been plagued by a confounding foreign body response essentially limiting in vivo sensor viability to weeks or, best case, months but certainly not years. The Glysens measurement engine brings real promise to the prospect of a multiyear, fully implanted CGM system.”

Glysens is not the only company focused on CGM implants. Senseonics Holding Inc., of Germantown, Md., received FDA approval of its Eversense 90-day implantable CGM in July 2018. The system includes a tiny sensors implanted under the skin of the upper arm, plus an external transmitter, worn on the body, and a mobile app to receive and analyze glucose readings.

In June 2019, the agency added a nonadjunctive indication that allows Senseonics to replace fingersticks for dosing decisions, although twice-daily calibration still requires fingersticks. The company is conducting the PROMISE study to support a 180-day version of the sensor.

Other competitors in the CGM space include Abbott Laboratories, Medtronic plc and Dexcom Inc. San Diego-based Dexcom is expecting a limited commercial rollout of its next-generation CGM sensor G7 late this year, followed by a larger launch in 2021. The company recently partnered with Livongo Health Inc. to sync its CGM with Livongo’s chronic care digital platform, enabling users to get health insights and personal coaching tips.

The global CGM market is expected to hit $1.3 billion by 2025, growing at an annual rate of 15.8%. Driving demand for the technology are growing rates of obesity and sedentary lifestyles leading to diabetes, particularly in developed countries, and increasing demand for user-friendly devices to help patients control their glucose levels. According to the World Health Organization, roughly half of all deaths can be associated with high sugar levels, largely by increasing the risk of cardiovascular disease. By 2030, WHO predicts diabetes will the No. 7 cause of mortality worldwide.