The biggest issue with having an insertable, subdermal CGM is that the sensors aren't able to last due to the gluco-biosensor component running out. The team at the Juvenile Diabetes Research Fund are making some groundbreaking progress on this issue.
It sounds as though they are using a new type of biosensor which is a live engineered cells which are enzyme based instead of the current/more traditional gluco-oxidase sensor. It is designed for long term use (stated 1 year) and would require less finger-prick calibrations, more importantly it would be more accurate than the current CGM's on the market.
Essentially, sensor would be inserted subdermally, with a wireless device worn on the skin.
The JDRF are looking at raising $80 million USD over the next 2 years to fund the project, in addition to the $42 million already pledged.
Exciting news for diabetics worldwide. Future technology of this kind could help improve lifestyles all over.
Cheers
Shmiddy-Dack
Further reading : https://www.meddeviceonline.com/doc/long-lasting-injectable-cgm-uses-live-cells-to-regenerate-sensor-0001