Are Implantable CGMs the Wave of the Future?

Science appears to be overtaking fiction as a continuous glucose monitor implanted under the skin for three months or more is now being sold in Europe and could become available in the U.S. this year. Though not without its critics, the new technology represents a significant step forward in the development of implantable glucose monitoring for diabetics.

“Implantables are the future,” says Mirasol Panlilio, Vice President of Global Sales and Marketing for Senseonics. “Whether we are talking about drug delivery systems, or monitoring systems, there are many implantables out there and many more coming.”

Sensonics’ Eversense is an implantable CGM sensor system that is now available in Africa and in many countries in Europe. It lasts up to 90 days between the need for reimplantation at a doctor’s office. Panlilio says. She adds that the sensor as now designed can actually last 180 days and will, in the near future, be marketed as such.

“It’s a fluorescence-based product implanted under the skin,” Panlilio says. “The technology means that it doesn’t have to be removed and reinserted on a weekly basis, like most of the other monitors now on the market,” such as those made by Abbott, Dexcom, and Medtronic that need to have their subcutaneous cannula replaced every seven to 14 days.

The sensor itself is about half the length of a matchstick and is implanted usually, but not always, in a patient’s upper arm. The sensor, which is housed in a biocompatible material, measures glucose levels from interstitial fluid just below the skin surface on a continuous basis, just like other monitors. Compared to other CGM monitors, Eversense stacks up favorably in accurately reading glucose levels.

“Senseonics’ Eversense CGM has shown exceptional results in a clinical study,” according to diabetesviews.com. “8.8% MARD (Mean Absolute Relative Difference), better than any CGM on the market. PRECISE II clinical study enrolled 90 adults with diabetes over 90 days of continuous glucose sensor wear. The study collected over 16,000 comparative data points with over 2 million glucose readings. A previous study has shown a larger CGM error: 11.4% MARD. This study was smaller, with only 24 adults. The result of 11.4% put Eversense between Dexcom G4 and Dexcom G5 in terms of accuracy.”

The Eversense, however, does not send signals directly from the sensor under the skin to a cell phone app or computer. There’s another, some say more cumbersome factor that’s also involved in the process of turning fluorescence into digital displays.

Users of Eversense have to wear a reusable and rechargeable “Smart Transmitter” directly on the skin over the sensor. The transmitter powers the subcutaneous sensor and delivers a vibration at low or high glucose readings. Attached with either an adhesive tape or armband, at least one reviewer of the product took some exception to the transmitter.

“Note that this wearable transmitter is larger than either the Dexcom or Medtronic CGM sensors currently on the market, and appears to have a long-ish adhesive strip holding it in place,” wrote Amy Tenderich on the website Healthline. OK, it doesn’t penetrate the skin, but come on… really? This is a design and ‘human factors’ issue if we’ve ever seen one, and we can’t help wondering if Senseonics queried any patients about their preference for this over the current CGM options. All of that begs the question: What’s the actual benefit? And would an implantable CGM—even without that box addition—prove to be something people really want?”

Some investors, for one, are betting the product will be something people with diabetes really want. The company’s initial public offering of stock in March 2016 raised about $45 million. Though short of a projected $60 million expectation, the IPO relied almost solely on the company’s premier product, Eversense.

Looking forward to fulfill those investor expectations, Panlilio says Roche, which describes it self as “the world’s largest biotech company,” is marketing Eversense in Europe, the Middle East, and Africa. Senseonics, meanwhile, is planning to market and distribute the sensor in the United States.

“It will require a lot of funding and resources and there will be challenges,” Panlilio says. “We’re a small company, and this will be new to us in many ways, but we have considerable experience.”

Senseonics has developed and marketed oxygen sensors for almost three decades and its leadership team is well acquainted with marketing diabetes care devices.

Panlilio also says that the timing for launching implantable sensor looks very good.

“At the most recent Diabetes Technology Meeting they had panels on CGMs that, for the first time, broke them out into needle-based and implantables,” she says. “And in our clinical trials people seemed to enjoy the product. It says a lot when you have about 700 people who have used our implantable and overall they have a positive experience with it.”

Ending up with that positive experience is the culmination of a lot of different experiences along the way, Panlilio says. Calling this the “Star Trek effect,” she says at first subjects in trials are excited about the new technology and how it might work. Then subjects get nervous because an incision is required in a doctor’s office to implant the sensor. After this subjects tend to become hesitant about continuing. They are, however, reassured when they see the sensor and realize the incision is so small that afterward it can be covered with a Band Aid. In the final step, Panlilio says, subjects become comfortable with the sensor once it is implanted and working.

“There are always going to be some people who we just cannot reach,” Panlilio says about the future of implantable technology. “But for those who are open to this new technology, it’s there to help them manage their diabetes better.”